International MarsWatch

Post-Opp

Mon, 02 Apr 2012 08:50:34 EDT

Well, we're not past opposition, but the images are still coming in (about 70 in the last month!), and looking great! Cap clouds over the various volcanoes are easy to see, as is the residual north polar cap and even clouds in Hellas Basin. When imaged in blue light, and stretched, the entire aphelion cloud belt can even be seen. Not seeing much evidence for dust storms, but then, this isn't really the season for them. Today, if the weather holds out here in South Jersey, our Rowan University Department of Physics and Astronomy will be holding an observatory open house where yours truly will be running an 8" telescope trained on Mars. We'll also be recommissioning our 0.4 m telescope (it was down for mirror cleaning and some analysis to come up with a solution to reduce high frequency vibrations caused by building air handling). If you're in the area, drop by! Mars Reconnaissance Orbiter is still going strong. In fact, in March the HiRISE instrument captured an image of a dust devil wending across the surface! And the MARCI instrument continues to create its weekly global images; here's the one fro 19–15 March 2012. According to the mission web site, MRO has sent back almost 159 TB (yes, terrabytes) of data. That's a lot of analysis yet to be done. Opportunity is still parked on the rim of Endeavour Crater for the southern winter season but doing some science even with its low energy levels. It's working on collecting microimagry and X-Ray spectroscopy of a nearby rock. And its even trying to get a low light panorama image set of its surroundings. Curiosity is still in cruise phase, on its way Mars. As of yesterday, it is halfway there; the countdown to landing is just over 125 days. The first two mid-course corrections have gone well. And, just in case you forgot about it, the 2001 Mars Odyssey is still going after 10 years in orbit; that makes it the longest running Mars mission ever!

Opposition!

Fri, 02 Mar 2012 10:06:13 EST

It's almost here! It was a great sight last night as I left the office to look up in the sky and see Venus, Jupiter, and a very bright, and very reddish, Mars. Granted, due to campus lighting those three, plus the Moon and Sirius were about all I could see... I'm really enjoying all the images being submitted. It is truly some impressive work and fun to go through the images over time to see the transformation of Mars from small round object as it came out of conjunction to the detailed world near opposition. This Saturday my home institution (Rowan University in Glassboro, NJ) will be hosting an open house and we'll have a small cadre of telescopes on the building rooftop [above the campus lighting!] so that any and all visitors can see Mars for themselves. Well, at least that's the plan...the weather report seems to be disagreeing with us but we'll make that call sometime mid-afternoon.

Approaching opposition

Wed, 08 Feb 2012 09:13:03 EST

Mars opposition is getting closer and imaging of the Red Planet is really stepping up. I want to thank all the MarsWatch contributors for their donations—just click on the Images link in the menu to see our journey so far. Again, if any Mars observers are maintaining their own site for their images, I'd like to hear from you (just click on my name below) and I'll add a like to your site at the bottom of the images page. Preferably a link directly to your Mars images page. In rover news, Curiosity (the Mars Science Laboratory) is under way to Mars after a successful launch last (USA) Thanksgiving weekend. The MSL team has put out a short story on the Mars Hand Lens Imager (MAHLI) and its calibration targets. The color chips are leftovers from the MER program (Spirit and Opportunity) which, assuming there was no degradation in the pigments, means MSL images will be calibrated in the same way as the MER images making intercomparison easier. As a side note: I can't help but wonder if the timing of the release of Disney's John Carter movie was chosen to coincide with opposition, or was chosen simply because March is the month of Mars. Or if they were just totally clueless and it's simply coincidence. I'm assuming it's the last one.

MSL Away!

Sat, 26 Nov 2011 01:55:58 EST

The Mars Science Laboratory rover, Curiosity, has lifted off and is on its way to Mars! It is scheduled to land next August after about 8.5 months of cruise.

Mars Science Laboratory Launch

Thu, 17 Nov 2011 10:42:01 EST

It's finally going to happen: the most ambitious rover ever created is going to be heading to Mars next week! The mission is known as the Mars Science Laboratory and the official name of the rover is Curiosity. It is currently sitting atop an Atlas V rocket awaiting its launch date of 25 November 2011—that's the day after Thanksgiving for those of us in the USA. The plan is to have it liftoff at 10:21 AM EST. The landing site, Gale Crater just south of the martian equator in Elysium Planitia was selected in July in a process that started back in 2006. The crater is somewhat degraded, meaning all kinds of interesting geology has been happening there. Recent work studying orbital imaging has found many channels that appear to fluvial in nature as well as rock layers that may be composed of water-altered materials like clays and sulfates. You can get even more info from JPL's MSL site.

Mars getting better

Wed, 26 Oct 2011 08:42:35 EDT

We're about halfway to the next opposition so Mars observing is getting better and better each day. We've been getting great imaging submissions to the site so be sure to check out the Images link on the left there. When this endeavor first started up 17 (wow!) years ago at Cornell by Jim Bell, the idea was to become a repository for Mars images with the goal of trying to get global coverage each day near opposition—which necessitated it being international since Mars rotates only slightly slower than Earth no one observer can see the full globe on any one day. It was great because there were many observers but nobody really had access to large amounts of disc space to store images or the ability to host their own web (and, then, ftp!) sites. Today this is no longer the case. We have just as many, if not more, people doing high quality observing and recording, both drawings and digital imaging. But many of them now have access to large, online, storage and web hosting. This is great! But it also means that there is no longer a one-stop shopping site for Mars imagery. I would like to reiterate that this site will happily accept submissions, even if you are hosting your own site; in fact, we would still like to meet our goal of getting global coverage per day. If we can't get all those images here locally, we can at least try to get the links to the sites of all the regular observers. So here's my plea: 1) if you can, please still submit images here directly [and send me anything you consider noteworthy about them, like if you start to see dust storms, etc. or 2) contact me with the web address of your personal repository so I can put them on the Links page and on the Images page. Also, if you have some kind of regular directory sorting and file naming scheme, could you let me know that? My near-term goal would be to try to have our database serve up links to your site's images whenever someone does a date/observer query. Thanks! And Clear Skies everyone! P.S. I was given word that a very active observer has recently passed away and his entire observatory, which is basically a refurbished cottage (and thus "real estate") is for sale. You can get all the details at http://www.galaxyviewct.com/. If only I lived in WA...

Mars conjunction

Sat, 09 Apr 2011 08:00:21 EDT

While Mars passes through conjunction, when it is in the same direction as the Sun from our point of view here on Earth, most observers are unable to continue working. But there two observers that can image Mars during this time: the Solar & Heliospheric Observatory (SOHO), a joint NASA and ESA mission, and NASA's Solar Dynamics Observatory (SDO). Both of them have coronagraph, a telescope with a central blank to cover the disk of the Sun so that images of the corona, or extended atmosphere, of the Sun. This means they can image relatively faint objects near the Sun—such as Mars in conjunction. Well, some folks at the Mars Express team used a tool called JHelioviewer, found the images containing Mars and put together a movie of Mars in conjunction.

New Observing Season

Thu, 24 Feb 2011 11:20:02 EST

The new Mars observing season is almost upon us; well, technically it started with the conjunction on the fourth of this month, but Mars is still a bit too close to the Sun to safely observe. However, I am now declaring the 2012 MarsWatch site "open for business". The images uploader appears to be running just fine. I've also updated the Opposition Information page with the details for viewing Mars at opposition. And, as always, you can visit Jeff Beish's Observing the planet Mars site for a detailed ephemeris and notes on what to expect when you do view Mars. Also, the MarsView link in the menu will let you virtually see Mars at just about any day/time you enter. Clear skies!

Best Mars maps ever!

Fri, 23 Jul 2010 12:04:52 EDT

So I'm sure that everyone has seen the Google Labs maps of Mars using the same mapping interface that their standard maps use. And I'm pretty sure most of you know that you can now add Mars to your Google Earth download. Well, it turns out that Arizona State University Mars Space Flight Facility is also hosting a Mars map site but this one has all kinds of data products! According to a recent JPL press release the data from the Mars Odyssey instrument THEMIS have now been incorporated into the map and these have resolutions down to about 100 m (about 330 ft) per pixel. To see them, once you are at the site, just click on the "Layer" drop-down list and choose either of the ones labeled with "100 m" in their title. For example, here we are zoomed in (not all the way, even!) on an area in the central Mariner Valley. Enjoy!

Mars Day

Wed, 14 Jul 2010 11:48:52 EDT

The Smithsonian Air and Space Museum has declared a Mars Day for this Friday 16 July, 10 am – 3 pm. See Martian meteorites, meet Mars research scientists, and see HiRISE images and even 3-D images. If I were going to be in town, it would be worth the 2-hour trip down to DC (I'll be at the AAPT meeting in Portland). On the MarsWatch home front, we're still getting image submissions and they are looking good! Thanks everyone!

APOD with interesting image today

Wed, 05 May 2010 08:17:31 EDT

The Astronomy Picture of the Day site, a must see every morning, has a great Mars related image today. Or rather, set of images. It shows a set of drawings of Mars from around the world done on the opposition. It even looks as if it is a complete Martian Sol. Check it out.

North polar region area dust storm

Sun, 31 Jan 2010 07:12:27 EST

I just got a report from Communications in Mars Observations of the Oriental Astronomical Association that an image submitted to them shows evidence of a dust storm over northern Acidalia and crossing over in the the north polar cap region. Check out the image or the the 2× zoomed version. There are currently no MRO MARCI images from yesterday released for comparison. I'll update as soon as possible.

Happy Opposition Day!

Fri, 29 Jan 2010 08:17:37 EST

Today Earth passes Mars as both planets continue their paths around the Sun. If you get a chance to get outside tonight, look over in the east just after sunset to see the bright orange-red planet as it rises. I'm going to try to pull out my C-8 and take a look—for those in the Easter US, we should be able to see a white north polar region (cap/hood) and the dark region Acidalia. Even Astronomy Picture of the Day is recognizing the opposition!

Closest approach

Wed, 27 Jan 2010 01:05:15 EST

Well here we are at Closest Approach day, anticipating the upcoming opposition on Friday. In honor of this event, my institution, Rowan University is going to host an observtory open house, so I get to stay late at work tonight. And it even appears that the weather will cooperate with us! In other Mars news, it is with some sadness that I pass along the report that the Spirit Rover is now the Spirit Lander. It appears that back when Spirit got stuck it got really stuck and without a tow truck on Mars, it's going to remain where it is. But it did have a great 6 year run moving about—and it can still do some great science. Since it is stuck it can continue to do very detailed studies of its local surroundings. Although there is still one glitch; its solar panels are currently tilted towards the south but with southern winter on the way, the Sun will be in the north. The rover team is working on trying to adjust the tilt enough so that it can stay alive during the winter. And while we're on the topic of winter death, the Mars Odyssey orbiter is on a listening tour; it is on the lookout for any signs from the Phoenix lander that died at the beginning of the northern winter last year. As summer returns to the north, it might be possible that the craft could warm up enough to reactivate. So far, no signals. My last bit of news is that the HiRISE team for the Mars Reconnaissance Orbiter have decided to put out a call for imaging targets. So if head on over to their site and put in your request!

MarsWatch history restored

Thu, 21 Jan 2010 09:21:15 EST

It was pointed out to me a short time back that some of our previous sites had gone missing---the dynamic nature of the World Wide Web being what it is, and the fact that some of those older sites were created back in the wild and woolly days of the web, it was not all that surprising. Servers die, backups get misplaced (or not made?!) etc. However, with a bit of work, we now have them back again! The 1994/5 archive at Cornell was moved to a new server there and restored. The 1996/7 archive, which was originally hosted by JPL in conjunction with the Mars Pathfinder mission, was rebuilt and is now being hosted at Cornell as well—thanks go to Jim Bell there for his efforts bringing them both online. The 1999 archive is back up and running at the Astronomy League, with thanks to Vern Raben for that effort. It kinda got lost in the shuffle of setting up a new server and site but we found it in the end. All of them can be accessed from the "Links" page—the link for which is over in the main menu on your left. These archives (along with the 2001, 2003, and 2005 sites here at Rowan) are essentially frozen snapshots from the last updates at the end of their respective observing seasons. As they are no longer maintained, you can expect that many of their external links are broken—and will probably never get fixed, sorry about that. However, the image archives should still be there and properly linked up; if you see any issues, just contact the respective webmasters. Oh, and don't forget, opposition is next week!

Awaiting opposition

Wed, 30 Dec 2009 09:36:12 EST

As 2009 comes to a close, the contributed images increase—opposition is almost upon us! I am grateful to all the contributing observers for the wonderful images and drawings and am glad that I still have this place for folks to post, although there are fewer contributors than back in '95–'03 which I assume is due to the ease with which folks can now set up their own web sites. Of course the other major use of this site is as an archive. So far, we have no storage issues, so if even if you are posting your images on your own site (PLEASE send me links—I'm thinking of making a section on the Images page just for those), as you run out of room and have to remove them, consider archiving the older stuff here. Some good news on the Mars front: MRO is out of safe mode. One of the issues was that a computer reset would have made it think it was back in storage at JPL—which would have had some catastrophic results. But it appears the proper software patches have been made.

MRO not doing so well

Thu, 29 Oct 2009 09:14:56 EDT

The Mars Reconnaissance Orbiter has been doing great science since it entered its mapping phase, from its incredible hi-res imagery, radar mapping of the subsurface, to mineralogic mapping the spacecraft has been quite a success. Over this past year, however, it has been having some trouble with its computers. There appears to be some stray voltage measurements that are causing it to go into safe-mode and stop working. Engineers are currently working to solve the problem so that it can perhaps return to doing science, although in its extended phase its primary mission will be to act as a relay satellite for future rovers so I guess that's the current priority for repairs. In the mean time, check out some cool of images taken by the MRO HiRISE instrument of the now defunct Phoenix Lander. The lander went dead when the Sun got too low to keep powering it—this was a planned death since the lander was at far northern latitudes and never expected to survive the fall and winter. With the return of spring and the recession of the north polar cap, MRO was able to catch sight of the lander again!

I'm back

Fri, 04 Sep 2009 02:56:25 EDT

I took some time off this summer and that took me away from the site for longer than I had hoped. On the plus side, I think I'm learning some more about radiative transfer modeling and that's always helpful. But the new semester is starting and I'm back in the office. We've already had some new observations uploaded and its great to start seeing the Red Planet again! The images are now posted and viewable by all. With some of the issues we've had, there have been some things changed and we've got most of the bugs worked out. What that means is that the Images link in the Main Menu is now the place to go to see and upload images. There is a link on the new Images page that will allow you to still view images from 2007–2008; eventually both databases will be combined into one. Thanks for your patience on this.

Busy month

Wed, 08 Jul 2009 09:07:46 EDT

This July is going to be a busy month, so instead of my analysis of what's been going on with Mars missions, I'll point you to blog post over at the Planetary Society; and if you aren't already a member, I encourage you to join! Since the observing season has begun, I have to point out that we are going though some software updates here at MarsWatch—I had hoped they would have been in place before observers were ready to upload, but that didn't happen. I will spare the details, but for now the "Upload an image" link on the Images page is no longer working. Until we get that fixed, if you have an image to upload just go to this page which works pretty much like the old one. Additionally, the current Images page only shows all the older submissions. To view new submission, use the new Images page (there are currently no images to view here). Eventually all of this will be merged together—I think you for your patience.

Mars mission updates

Mon, 15 Jun 2009 11:15:57 EDT

It seems I let the entire month of May and half of June go by without posting. The rovers have been roving, there were some glitches and reboots with a rover and with MRO, and Mars Express is into its third mission extension. Things seem to be going so well I guess we all get into a complacent mode with keeping track of what's happening. The Mars Reconnaissance Orbiter had another reboot episode earlier this month and that's being looked into by the engineers. The HiRISE team has posted some new images including one of the so-called "cryptic region"—an area around the south pole that says very cold despite getting darker (indicating loss of ice/frost). One interesting bit of work-in-progress comes from the Shallow Radar (SHARAD) instrument. It was designed to look for liquid water and as such has been studying gully features seen in parts of the Martian highlands. These features look like certain gullies on Earth that are formed due to the movement of underground liquid water. So far, no signs. Opportunity, having done some amazing work leading to a better understanding of the water history of Mars, is now trucking its way along a 10 mile (16 km) path to the crater Endeavor—bigger than any crater it has looked at yet. In eight months of traveling, it is now about 1/5 of the way there. Back in early May, Spirit got stuck in some particularly soft soil and the team is working on a solution. As part of this effort, they even used the microscopic imager to look underneath the rover itself. It's an interesting picture made more so since this is not how this camera was ever intended to be used. Engineers are a very resourceful lot!

Mars in Google Earth

Fri, 10 Apr 2009 09:22:08 EDT

If you haven't already downloaded and spent hours flying around the globe using Google Earth, well, I highly recommend it. It's an advanced version of their web-based mapping software. Quite some time ago, Google Maps added in some astronomical maps. You can use the web-based server to look at the Moon or Mars. A short time ago, Google took these 2-d Mars maps and married them to their 3-d Google Earth program along with all the 3-d (topography) data. The results is a desktop application that runs under all three of the major operating systems (Linux, MacOS X, and MS Windows). Now most of this falls into the category of Old News but what got me thinking of it again was this blog post that points out some of the finer points and little-known-features of Mars in Google Earth. The one I found the most fun is the Rover Tracks—you can follow both Spirit and Opportunity on their entire journeys from start to (almost) where they are right now. Download, install, and have fun!

Southern summer—Dust storm starting up?

Thu, 02 Apr 2009 02:55:59 EDT

I found this blog post over at The Planetary Society discussing an increasing daytime upper atmospheric temperature in the southern hemisphere of Mars. Right now Mars is well into its northern autumn or southern spring. This means that, due to the tilt of Mars (about the same as Earth's), the southern pole is beginning to be pointed more directly towards the Sun. The increasing sunlight leads to increasing temperatures both on the ground and in the atmosphere. It also turns out that as the south moves into summer, the heating is even greater than it is in the north since Mars is about 35 million miles closer to the Sun (Earth's orbit varies by only about 5 million miles). The heating and pressure difference during southern summer can loft dust up into the air. This dust can heat up very quickly during the day but it also cools quickly overnight. So if there is an increasing amount of dust in the air, we would expect to see more summer heating in the daytime atmosphere than in the night time atmosphere. Well, the Mars Climate Sounder aboard the Mars Reconnaissance Orbiter is seeing just that. The MCS measures the amount of infrared light emitted by the martian atmosphere by looking at the limb of the planet—so the background is just cold, dark, space. You can check out the changing MCS measurements over the last few days and see the images at the team blog site noted above.

Liquid water on Mars?!

Mon, 30 Mar 2009 10:54:08 EDT

A fellow MarsWatch'er pointed me to notices of some very interesting work that has been presented at the 40th Annual Lunar and Planetary Science Conference (I don't usually go to this meeting and had not yet gone over the abstracts). The work itself was presented on 23 March and reported on rather quickly by friend-of-planetary-science Kelly Beatty at Sky & Telescope. It appears that some photos of the leg strut of the Mars Phoenix lander showed what appear liquid drops clinging to it. What makes this so amazing is that water on Mars simply can not exist in the liquid phase. Why is that? It's due primarily to the atmospheric pressure. For example, if you put water into a pot and seal a lid on it, you can heat that water far above the standard boiling point, and thus cook food faster—that how a pressure cooker works in your kitchen. On the other side, those who have lived at altitude know that water boils at a lower than normal temperature. Back when I was in Laramie, Wyoming we used to have fun watching students' faces when they measured the boiling temperature in the lab. It never reached 100°C but instead boiled in the low 90's. This is one reason for "high altitude" baking directions. The lower boiling point is because there is less air pressure above the liquid making it easier for individual water molecules to leave the liquid surface. It also depends on the local humidity, but that is temperature and pressure dependent as well. So now if we go to Mars where the air pressure is about 1% that of Earth, it is very easy for water molecules to leave a liquid surface; in fact, individual molecules can easily leave a solid surface so the ice will simply sublime away. You can see this effect in your own freezer if you leave ice cubes in there for a long period of time—they decrease in size but never leave behind a puddle of liquid. So how can we have a picture of liquid water on Mars? The key is salts. Those living in northern climates know that adding salt to ice lowers its melting point. This means that it can be liquid at colder temperatures and your sidewalk won't be icy. Salts also increase the boiling point so that you can have liquid at higher temperatures. Combine the pressure and salt effects and, according to Nilton Renno and his collaborators you can get liquid brine on Mars. You can see a summary of his work, and some pictures, at this page at the University of Michigan where he does his work. Of course, the most interesting point of this is that liquid water appears to be the most important ingredient of life. And now we have it on Mars.

MarsWatch glitch

Wed, 04 Feb 2009 09:57:30 EST

A while back I received notice that some images from our site had gone missing. It turned out to be far more severe than that—all of the 2007/8 images had gone missing. Seems some hack-bot script had hijacked my space on the server and in the process, deleted all the images. And me without an archival backup! I sent out a message to all contributors to ask for resubmission and the first reply I got back, from Ljubomir Djurisic, said that he had done an entire archive of the images up through about mid-June 2008. This recovery saved me a lot work so my thanks go out to Ljubomir. For the images that came in after that, I have been able to contact those observers and have also recovered those—thanks to them for helping! I think the archive is good now; the problem is fixed and we should be fine going forward. Just a note to the concerned: the hack was not anything that could affect visitors to the site, that is, no viruses were planted for spreading so you have nothing to fear for uploads during the next apparition.

Spirit acting up

Mon, 02 Feb 2009 10:14:42 EST

A week ago last Sunday (28 January) Spirit seems to have had a "mental" hiccup. On its 1800th sol (20 times longer than it was expected to work) it reported that it had received its commands to move but chose not to. It also failed to record its activities for that day into its memory. While it could be that Spirit is getting old and forgetful (a condition with which I can sympathize) it may be more problematic than that. When it was put through its paces to find the Sun and reorient, it worked, but the Sun was not were it was expected to be. This means the rover was not in its expected orientation. This might mean that some of its attitude sensing hardware (gyroscope and accelerometer) may be damaged. The rover team is still working on diagnosing the problem. So far, Spirit seems to be following commands, taking pictures, saving info and downloading it. The team will test the attitude hardware and if that checks out, Spirit may resume its journey.

Methane on Mars

Thu, 22 Jan 2009 10:45:21 EST

Big news: NASA says there's methane on Mars! Why is this big news? Well, here on Earth most of our atmospheric methane is produced by little microbes in the stomachs of ruminants (e.g. cows and caribou) which makes one wonder if the methane on Mars is also produced by living bacteria. Back in 2003 three groups reported possible discoveries of methane using the technique of spectroscopy—you break up the light from Mars into hundreds or thousands of colors, then look for "missing" light. The missing colors were absorbed by specific compounds or materials and can be used as a fingerprint to identify them. It's really not quite this simple in practice, but with a lot of diligent effort, it really works quite well. One group (Mumma et al.) was working from the NASA Infrared Telescope Facility, another was working from the Canda-France-Hawaii Telescope, and the last was using data from the Planetary Fourier Spectrometer on Mars Express. Since then they have all been working hard to confirm their discoveries by gathering more/better data, improving analysis techniques, and working to account for all the known variables in their models. So a few days ago, the fruits of that labor were announced by NASA. Of course, methane can be produced non-biological means. One such method is that it could have been created during a comet-crash on Mars. One science group calculates that impacts into the Martian dust could have produced enough methane, an efficient greenhouse gas, to have helped keep Mars above freezing for quite some time. Of course, that methane would be long gone today as sunlight rapidly destroys it. Another idea is that olivine, a mineral discovered to be in one of the methane areas can be chemically altered by water into serpentine to produce methane. This requires relatively warm, liquid water and so, if this is the mechanism, it must happen at depth and during warmer seasons. The produced methane would then seep out of cracks in the rocks and soil, also during warmer seasons when the ice in the cracks is more likely to have sublimated away into the atmosphere. Either way, biologic or geochemical, this discovery is quite exciting! For more scientific details, you can check out Google-Scholar.

MRO Completes Primary Mission

Fri, 12 Dec 2008 09:58:20 EST

I was just sent a press-release e-mail giving some of the details of the MRO mission now that it has completed its primary 2-year science phase. First, the good news: it has been approved for another 2-year phase for science operations. This is great as the orbiter has only sent back about 73 TB of data—yes, terabytes. As in, more data all previous Mars missions combined. One terabyte is 1,099,511,627,776 bytes (2⁴⁰) or the equivalent of about 132,000 introductory physics textbooks—you know, those 9"×10" jobs that are a couple inches thick. So MRO's data would fill nearly 10 million such tomes. To quote from the release: "Since moving into position 186 miles above Mars' surface in October 2006, the orbiter also has conducted 10,000 targeted observation sequences of high-priority areas. It has imaged nearly 40 percent of the planet at a resolution that can reveal house-sized objects in detail, with one percent in enough detail to see desk-sized features. This survey has covered almost 60 percent of Mars in mineral mapping bands at stadium-size resolution. The orbiter also assembled nearly 700 daily global weather maps, dozens of atmospheric temperature profiles, and hundreds of radar profiles of the subsurface and the interior of the polar caps." This has been a very successful mission and all I can say is congratulations to all those scientists and engineers who pulled it off. I'm looking forward to another 73 TB of data!

Mars as Art and MSL

Mon, 08 Dec 2008 10:10:12 EST

Last Saturday I was listening to WHYY's broadcast of Studio 360 which is a great show covering the gamut of the arts. And on this particular day there was a nice piece on the rovers' PANCAM instruments—the two-eyed cameras on the "head" of Spirit and Opportunity. I have to admit that I get so buried in the science aspects of imaging that I don't always step back to just admire the view; there really is a majesty in these images. The best part is that, since the cameras are mounted at about human-eye-level, the views are very close to what you would see if you were standing there yourself. Fortunately, we have Jim Bell in charge of the project and he sees both the science and the art. He's even published two books collecting and discussing some of the best images from the missions. Postcards From Mars that tells the story of sending the rovers and their first views, and Mars 3-D that is a collection of the stereo-images, complete with built-in red/blue glasses. Jim was interviewed for the Studio 360 piece which you can hear, and download, from their web site. In other rover news, the next one to go, the Mars Science Laboratory has been delayed. It was intended to be launched in December 2009 but various technical difficulties have cropped up and now it is being scheduled for the next launch window in 2011. Of course, this means a tightening of the budget for other Mars missions, and a possible push-back of other 2011 probes, but as of yet nobody knows to what extent. It also means there will be no US Mars mission for the 2009 window.

Even more ice!

Tue, 25 Nov 2008 04:02:32 EST

One of the instruments on the Mars Reconnaissance Orbiter that seems to have not garnered a lot of press is the Shallow Subsurface Radar or SHARAD. I guess that's because it doesn't return a lot of pretty pictures although the radar information it does return can be put into picture form. SHARAD sends out a high-frequency pulse of radio waves that penetrate the surface. What happens to those waves (if they return, how they return, and how they are modified) is a complex function of what they bump into on the way down. In this way, the SHARAD team intended to look for subsurface ice layers—layers deeper than the Mars Odyssey Gamma Ray Spectrometer (GRS) could measure. One of their prime target were these lobate debris aprons in the mid-latitudes (e.g. 35–65°). They had been first photographed by Viking orbiters and they were curious in that they appeared to have smoothed out features that one would expect of flows that were lubricated by water or ice mixed in them as opposed to just being massed of rock and boulder that had slumped. Well, word from the SHARAD team is that in these regions, they get far more radar return than if there was just rock. The measurements they make imply a very thick layer of ice below a "thin" layer of debris (if the debris were removed, the ice would begin sublimating). Not only that, but the extent of the ice goes on for miles. So what are buried glaciers doing so far south? It turns out that the axial tilt of Mars, currently about 25° (very similar to Earths 23.5°) wobbles significantly. The technical term for this motion is nutation and it is tied very closely to climate change. On Earth this polar wobble is fairly small, about 2.4° but it, combined with other orbital variations, leads to a cycle of ice ages on an about 100,000 year period. Since Mars doesn't have the stabilizing effects of a large moon (due to a physics property known as conservation of angular momentum—why spinning top is harder to knock over than one that isn't) its axial tilt can swing wildly from about 15° to 35° which, combined with its significantly more elliptical orbit, can lead to great swings in climate. Based on models and an understanding of climate at a general level, back when Mars had a much larger tilt it could have supported vast areas of glaciers down to low latitudes. If these then get covered up by dirt and debris, they could survive that way now that the axial tilt is much less. So these results appear to confirm models of early Martian climate.

Goodnight Phoenix

Tue, 11 Nov 2008 07:01:44 EST

I'll resume some discussion of the DPS presentations shorty; I'm currently at a workshop on Mars Atmospheric Modeling which is really interesting and I'll share some of what I'm learning here. It's amazing how much "we" really do know and understand about the physics of climate! In the mean time, I thought I'd let everyone know that the Mars Phoenix mission had officially ended. Since it is at such a high latitude, as autumn progresses the days get shorter and the Sun gets lower in the southern sky, just as it does for folks in northern Canada, Scandinavia, and northern Asia here on Earth. This means less sunlight to charge the batteries and thus less overall power to keep the craft operating. The engineers had begun a program of systematically shutting down heaters and instruments in order to keep it running as long as possible. But on 2 November, they lost contact with it and as of yesterday, with no further contact, they declared the mission over. I'll have more on the incredible science that has been done—which I learned about at the DPS meeting—soon. I've got to get some breakfast and then head off to conference sessions.

Hydrated Silicates—More from the DPS

Thu, 23 Oct 2008 08:35:43 EDT

We've known for a long time now that there is water on Mars. Well, more specifically, we've known there is water vapor in the atmosphere and water ices at the poles and in the clouds. In the late 70's the Viking 2 lander confirmed surface frosts existed. The big question about water is not whether on not its there, but whether or not liquid water existed and if so, how long. As science and technology progressed scientists been able to confirm various minerals on Mars that, at least on Earth, usually form in the presence of liquid water. We call these hydrated minerals and many of them start out as other minerals but then get chemically altered by water. Typically, the water breaks up into H⁺ (hydrogen) and OH^- (hydroxyl) with the latter bonding to the mineral. Other times, the entire water molecule gets stuck into the mineral. One important class of these is the phyllosilicates. Silicates are minerals that are derived from the SiO₄ tetrahedral molecule—it's sort of like methane but with silicon and oxygen instead of carbon and hydrogen. This makes sense if you look at a periodic table; silicon is in the same column as carbon which means it behaves similarly in general chemistry—this fact is what leads to sci-fi writers talking about "silicon-based life". You can stick these triangular pyramids together into a huge single crystal where each Si shares all of its O's with another Si, so you have Si + 4 "half" O's or SiO₂ which is quartz. You can also connect them into pairs or chains or double chains or sheets or even rings. The sheet form is the phyllosilicate group that contains things like mica and clays. So one of the DPS talks by Eldar Noe Dobrea, now at the Jet Propulsion Laboratory, discussed his study of an outcrop of phyllosilicates in the highlands around Mawrth Vallis. Using new high resolution images and spectra from the Mars Reconnaissance Orbiter he hypothesizes that different types of phyllosilicates weren't put there over different times, but rather that the layering suggests a primary layer of iron and magnesium phyllosilicates was put down and the the upper level interacted with liquid water leaching out some elements and leaving behind aluminum phyllosilicates. Eventually, this was covered up by some other rock and then parts of this layer eroded away by the wind "sandblasting" some parts of this top layer. A second talk on hydrated minerals by James Wray was about trying to infer formation times and conditions of sulfate minerals. Sulfates tend to form out of the salts left behind when water containing them evaporates—more evidence of liquid water on Mars. However, in this case his work seems to indicate that all these sulfates formed during the earliest geologic period on Mars, called the Noachian Epoch which ended about 3.5 billion years ago.

At the DPS

Mon, 20 Oct 2008 12:29:14 EDT

Last week I was at the 40th annual meeting of the Division for Planetary Sciences of the American Astronomical Society. This is one of the major professional conferences for planetary sciences and I try to get there every year to see what's new in- and outside of my Mars area of expertise. It's also a chance to meet up with some of my fellow scientists and chat in person to swap ideas. So I thought I'd try to discuss here some of the latest Mars science. A caveat: the things discussed here are the talks and papers that jumped out at me as "easily translatable". Much of the state of the art in Mars science is incremental in nature and those results just don't make for a good story for the masses. Thus, over the next few days I'll be picking and choosing and writing about just a few of the things I heard about. The first talk was on a new look at a martian chronology. Trying to get a good time-history of the various geological formations on Mars is very difficult. In general a technique called stratigraphy is used—in general "things above" are younger then "things below" such as a crater in a lava flow bed would mean that the crater is younger. Seems simple enough but it gets complicated very quickly. Craters can create flows; they can have secondary cratering and/or rays; flows and future impacts can "erase" older features. In addition to this technique we have crater counting where you add up the numbers of crater in one area and compare to the count in another area. If we assume that surfaces start crater-free, then the surface with more craters is older than the one with fewer craters. However this is complicated by crater sizes. The current model of solar system formation says that as time goes on there are fewer and fewer "large" impactors so if you have two surfaces with the same number of craters but one of them has both large and small ones, its probably older than the one with only small ones. For Mars this gives us three major epochs: the Noachain (large and small craters and lots of them), the Hesperian (only small craters, but lots of them), and the Amazonian (only small craters but fewer of them). The surfaces from these general ages are fairly contiguous.[1] These general ages can be subdivided somewhat based on other geologic processes and features and can even be compared to Earth, Venus, Mercury, and our Moon[2], although since we have not been able to do any radioisotope dating for Mars, Venus, and Mercury, the absolute dating is still uncertain. There is another wrinkle. Some mid-sized craters that kicked up material so as to create secondary cratering so now some of the small stuff may really be caused by this debris and not "real" craters. One of these craters is called Zunil and the discovery of its secondary system calls into question the crater-count chronology of Mars and throws it off by factors of 700–2000. That's a big uncertainty even in a fairly uncertain science. Well, the very first Mars talk at DPS was by William K. Hartmann was on a new assessment of these errors. He and his collaborators used newer data from images of Zunil-type craters from the Mars Global Surveyor Mars Orbiter Camera. Essentially, they went back to these images to search for the small (10–25 m sized) craters that previous studies did not find. Well, the found them. And they found that the ages they get using their numbers seem to fit the older chronology estimates to within a factor of 2—4. Thus, they conclude that there is no major problem with our age estimates.

Let it snow, let it snow, let it snow!

Thu, 02 Oct 2008 10:51:52 EDT

The big news from Mars is the first real sighting of snow! Although the highs are still a balmy -35°F (-35°C) so the snow sublimes (changes from ice to vapor) before it reaches the ground. Back when I lived in Wyoming we'd see this effect with rain. You could look off in the distance (the high plains can be quite flat in areas) and see rain falling from storm clouds that never reached the ground due to the extremely low relative humidity near the surface and the greater relative pressures between ground and cloud---compressional heating. This phenomenon is known as virga. The way Phoenix "sees" this martian virga is though the use of its LIDAR instrument provided by the Candian Space Agency. LIDAR stands for LIght Detection and Ranging (c.f. RADAR = RAdio Detection and Ranging) which effectively shines a (in this case, green) laser into the air then detects the reflected beam. Since the LIDAR uses short wavelength visible light (instead of longer wavelength microwaves) it can "see" much smaller objects—in this case aerosols of ice and dust. By measuring the amount of returned light they can get an idea of how dark the material is so as to tell the difference between dust and ice. By effectively timing how long it takes for the return beam to arrive, the get altitudes. Presumably, they could also measure shifts in the laser wavelength to measure vertical speeds of aerosols, but I'm not sure they are doing this. This is how the new "laser radar" works that various highway patrols are now using—since the beam is narrow, by the time you detect it's in use, your speed has been measured as they don't "leak" like RADAR does. Nominally, the LIDAR team gets to take 15 minutes of data 4 times per sol (a martian day, which is about 30 minutes longer than a terrestrial day). The data from sol 99 at around 05:00 (5 am) Mars Local Time, the LIDAR picked up bright aerosols that were below the clouds and appear to be falling and being blown sideways. Since it is still far too warm for there to be any CO₂ ice in the atmosphere, they conclude it must be water ice. And falling water ice is... Snow! Interestingly, there has been a lot of work by atmospheric and planetary scientists that infer the seasonal polar ice cap is, at least partially, created by falling CO₂ snows. Recent (1998) work by FranÃ§ois Forget and his colleagues attempted to model the energy balance for the entire atmosphere of Mars. It's a very difficult problem to solve (for those who care, it starts with what's called an integro-differential equation for radiative tranfer) and solution found that conditions should exist such that CO₂ should condense in the air and fall. They were even able to accurately match some confusing infrared measurements over martian poles taken by the Viking orbiters. I don't think Phoenix will still be "alive" by the time it could see CO₂ snows.

Rovers warming up

Thu, 25 Sep 2008 11:03:34 EDT

Since the two rovers are south of the martian equator, they have been going through their winter (while Phoenix enjoys its northern hemisphere summer). It's now past the solstice and the days are lengthening and warming up for Spirit and Opportunity. Since early August Spirit has been biding its time, keeping its batteries charged, keeping warm, and working on a the Bonestell panorama—a 360° picture in all 13 filters of its PanCam instrument. It's waiting out the winter sitting on the southern end of Home Plate plateau. As reported last year at a major scientific conference by Steve Squyres, principal investigator of the rover missions, this plateau is composed of broken up rocks that were most likely formed in a volcanic explosion then worked over by wind erosion. Spirit also found that much of the local "soil" is very high in silica (SiO₂) which could be an indication of rock alteration by very high temperature flowing water. On Earth, such an environment is more than capable of sustaining microbial life! Opportunity has completed its nearly one Earth-year long investigation of the interior of Victoria crater. After driving around the rim the rover entered and began its study of the excavated layers of rock. It then began its climb out, and by the beginning of this month was back on the rim and is now getting ready to, once again, put the pedal to the metal and drive off 12 km to an even bigger crater south of Victoria. Although it may never get there, its worth the try as this crater has an even thicker exposed rock layer to investigate. This means we may get a look at even earlier rocks than we've seen so far which can give clues about an even younger Mars environment.

Busy, yet quiet

Thu, 28 Aug 2008 09:19:46 EDT

With the shrinking apparent size of Mars, it dimming, and its nearness to the Sun, it seems that ground-based imaging is all but over. Granted, the current "apparition" won't end until the next conjunction in early December this year, but there haven't been any new images here since the end of July. Thanks to all the image contributors for their great work and dedication! On the busy side of things, Phoenix, the rovers Spirit and Opportunity, and the Mars Reconnaissance Orbiter and Mars Express continue their work. At the Phoenix site, summer is ending which means it will start to experience sunsets. Since Mars is tilted about 23 degrees on its axis, for part of the year its north pole faces the Sun; this means that north of a particular latitude even though it spins, there are parts that are never out of the sunlight. This is the same season-making process as here on Earth. The effects on Mars are easily seen—average air pressure changes, average temperature changes, and the ice caps shrink and grow. In fact, the Phoenix lander is far enough north that as the seasonal cap grows, it will bury the lander under a thick layer of ice. Of course, this will happen well after permanent night arrives at the site and the lander has stopped working. But until then, Phoenix will continue its mission—NASA approved an extension from its nominal end date of 26 August 2008. Now it will keep digging and studying the martian soil until at least the end of September.

Land of the Midnight Sun

Wed, 30 Jul 2008 11:21:29 EDT

So here's something I hadn't really thought of before: since the Mars Phoenix Lander is so far north, it is above the arctic circle so for some number of days, the sun will never set (just like for folks in northern Finland, Scandinavia, and Alaska). What made me realize this was that the camera team took time out to record this phenomenon. They put all the images together to make a really nice composite image of it.

MER Update

Tue, 15 Jul 2008 11:48:21 EDT

In all the Phoenix flurry of news, let's not forget that the MER program is still going strong. Granted, it has been winter where they are, so one might expect both Spirit and Opportunity to be in hibernation mode to conserve energy until the Sun gets back to higher altitudes. Having been working on Mars for about 1600 sols (martian days), the rovers have far outlived any expectations and continue to do significant work. Spirit has been in a power-saving mode for some time now due to the fewer number of daylight hours, coupled with residual dust on the solar panels and in the air. During this time is has basically been "beeping" to let folks know its still operating; it has also been measuring the dust optical depth with its panorama cameras every few days. But now that the winter solstice has passed, things will be brightening up soon. Opportunity has continued its journey down into Victoria Crater. It has been parked taking a full resolution panorama of the nearby Cape Verde layered cliff and a nearby region to give the images a larger context. There's no link to this yet as it's going to take weeks to get all the image sections beamed back to Earth. You can see travel maps for both the rovers—the distances covered are incredible! Spirit has covered a total of 7,528.0 meters or 4.7 miles (as of 1 July 2008) and Opportunity has covered 11,723.94 meters or 7.28 miles (as of 4 July 2008). Impressive!

"White stuff" on Mars

Tue, 24 Jun 2008 10:18:17 EDT

The mystery of "white stuff" composition is pretty much solved. After the first scooping, an image of the area showed a white substance within the trenches that could have been either salts or ices. However, comparison images taken 4 sols (martian days) later, showed that some of the white material has disappeared. The prevailing thought is that it must have been ice that sublimed away. You can read the full press release for more details. Of course, Jon Stewert of The Daily Show, in his report on this event, has an entirely different interpretation. Warning, the clip from that link is rated PG. I guess we know that the Phoenix mission has "made it" in popular culture when it's getting spoofed on The Daily Show. In other news, data and images from the CRISM instrument aboard the Mars Reconnaissance Orbiter has found evidence for gypsum and other sulfates north of the Phoenix landing site. Gypsum is a water-bearing calcium sulfate mineral that is found on Earth in various sedimentary deposits. That is, it forms out of salty waters. Clearly, this has some implications on the past environment of the region that are very intriguing.

Baking Mars

Wed, 11 Jun 2008 02:38:09 EDT

Things are going well with Phoenix these days. After a minor false start, there is now some martian "soil" in the Thermal and Evolved-Gas Analyzer (TEGA) oven. On the first attempt, none of the material passed through the millimeter-sized screening. This implies that the ground sort of clods together—which itself may be an interesting observation since it seems to be different from the material at other landing sites. But persistence paid off and with some jiggling of the screen, and perhaps some changes to the clump over time as it sat there for a few days finally allowed material to fall in and fill the oven. In orbiter Mars Reconnaissance Orbiter released an interesting image that shows one of the powers of using the infrared. In this image of the winter pole shows that in the IR the two types of ice (H₂O and CO₂) are distinguishable even though both appear white in visible light. The reason for this is due to the chemical and structural differences in the two ices. The molecular bonds can be thought of as short springs that vibrate only at specific frequencies and energies. Infrared light has the amount of energy needed to excite these vibrations, but only very specific wavelengths in the infrared. Since the "springs" in the two ices are different, the specific infrared light absorbed to start the vibrations is different. So one type of ice will look dark at one wavelength (absorbing) while the other looks bright (not absorbing, so reflecting); the situation reverses at other wavelengths. This is the science of spectroscopy!

The Phoenix has landed!

Mon, 26 May 2008 09:29:33 EDT

It's down, safe and sound! The first radio signals were received 7:53:44 p.m. Eastern Time confirming that the lander had touched down about 15 minutes earlier. If you go to the main Mars Phoenix site you'll see a picture of the landing pad on the ground—one of the first images transmitted back. Since then, the solar panels and instruments have deployed and there's been a trickle of images coming back and posted to the site's Phoenix Screen Saver. I just tried it and there are even a couple color images!

Five days to go!

Tue, 20 May 2008 10:04:59 EDT

After launching at about 4:45 am on 4 August 2007, traveling for months, the Mars Phoenix is set to land this coming Sunday 25 May 2008—and I can't wait to see the first images! If you want a sneak peek of the "seven minutes of terror", known officially as EDL (entry, descent, and landing), the Phoenix team has a really nice simulation video at their site's videos page. From their site, the lander will have a mere seven minutes to execute a sequence of maneuvers that will slow the craft from its incoming speed of almost 13,000 mph to the 5 mph needed for a save touchdown. That's right, touchdown. Unlike the last two rovers, this one is not going to inflate balloons all around it and bounce to a stop. Mainly because its just too big for that trick to work. The rovers come in at about 185 kg (about 400 lb) but Phoenix is a whopping 350 kg (about 770 lb) and from what I read, the Spirit and Opportunity were at about the upper limits for the "bounce landing" to be safe. Mars Phoenix is the rebirth of two missions, the Mars Polar Lander (which crashed on Mars back on 3 December 1999) and the Mars Surveyor Lander '01 (a mission that was canceled as part of NASA restructuring of the Mars Exploration Mission). Phoenix will be landing in the far northern latitudes where previous missions (e.g. Mars Odyssey) have determined the presence of large amounts of sub-surface ice. Phoenix has a robotic arm and digging scoop so it will be doing some close up studies of the martian "soil". Included on board is a sort of next-generation "search for life" experiment that was back in the mid 70's by the Viking landers. All in all, this is going to be a very exciting mission!

Trying to catch up

Mon, 05 May 2008 10:24:38 EDT

One last day, then a final and the semester is done. In the mean time I'm trying to play catch up with all my Mars-related reading and seeing what needs to be posted here as highlights. One nice thing is that we are continuing to get great images submitted. Even at the 5–6" size, you all are still going strong—Thanks! There's some really interesting results coming down from the ESA Mars Express—the MARSIS instrument (radar sounding) has been busy mapping the Mars Underground! You can check out their official press release on it. Now, the big news results were published some time ago (e.g. an inventory of south polar ice) but this new stuff includes making 3-d imagery with the data to put it all in perspective. It's quite possible that this instrument could "see" down to depths as much as 20 km; that's almost as deep as Olympus Mons is high! And let's not forget the incredible imaging being done by the High Resolution Stereo Camera (HRSC). This is the one that's making all kinds of 3-d topographic images of Mars. To date, they've imaged about half the surface of Mars. One of the more recent releases is a slew of images of Hebes Chasma. This is a canyon that is nearby to the northwest of, but separate from, Valles Marineris. One of those images is even an anaglyph—one of those red-blue 3-d images, so you'll need to get out your 3-d glasses.

Phobos at APOD

Mon, 14 Apr 2008 08:52:42 EDT

The MRO HiRISE image made it to the Astronomy Picture of the Day today! Of course, you can see more details about the image by going to the HiRISE site at UofA LPL directly.

Too long a delay...

Wed, 09 Apr 2008 02:36:12 EDT

I've let myself get swamped with midterms and lagged a bit here. But I'm now (almost) caught up and will be trying to get back to more meaty posts. But in the mean time: 1) We're still getting some great image submissions so be sure to check them out. Impressive! 2) MRO has released a really cool, color, pic of Phobos! I haven't had a chance yet to sift through the science in the image, which is one of the things I like to do with this blog, but it was just too cool to let pass! The Phobos image is not "true-color" since it's not Red-Green-Blue but more like Infrared-Red-Aqua. One thing it does show is that there is some relatively "bluer" material near the major impact crater implying the stuff is less processed and thus "younger" than the average.

Mars Odyssey update

Tue, 19 Feb 2008 01:56:26 EST

A couple days ago I got my suite of update e-mails from the various NASA lists I'm. It continues to amaze me just how much information we can get by "simply" looking at an object! It's what makes this game we call science so much fun. For example, one of the featured Mars Odyssey THEMIS images this week is of the Aram Chaos— a region in western Arabia and the east end of Valles Marinaris. Using this image, as well as data from the MGS TES and MGS MOLA, scientists Tim Glotch and Phil Christensen have been able to put together a nice chronology of events that shaped this region. These events include a period where the debris in this region was saturated with water that eventually froze. Along with the morphology of the region, the THEMIS team has been able to use its spectral mapping capabilities to map out the grey-hematite in the basin that was originally discovered by the MGS TES (about the same time it found this stuff in Meridiani, where Opportunity was plopped down). This type of hematite is usually formed in the presence of liquid water. All this evidence together can be used to infer that Aram once had a "lake" here. Now, the dating of this hematite region is different from the other regions discovered, so this implies that either Mars had a fairly long wet period or, perhaps more likely, several "catastrophic events" that warmed select regions for short periods of time, allowing them to have liquid water. Once again, the whole reason for looking for events/areas of liquid water is because, near as anyone can tell, it seems to be about the only actual requirement for life. Based on all the successes of Opportunity at Meridianni, perhaps these results mean we should send a rover to Aram in the near future.

No collision with Mars

Tue, 15 Jan 2008 10:39:19 EST

I was just checking out the NASA Press Release site to update the odds of the asteroid collision with Mars, only to see that the addition of new observations of the asteroid have helped to better plot its orbit. Now the odds of a collision are pretty much zero. Well, OK, so the odds are 1 in 10,000—far better than winning the lottery, but I wouldn't be putting any money down on it. The Near Earth Object Program is predicting that the asteroid will pass no closer than 4000 km, and most likely be about 26,000 km away. Oh, and these are center-to-center distances, so that last one means that it'll fly over Mars' surface at an "altitude" of about 22300 km (or 13900 mi). In astronomical terms, this is a near-miss (or maybe we should call it a near-hit?). Note that our Moon is about 384400 km away---so the passing distance is about 5% of the Earth-Moon separation. In other news, the late Chick Capen has had martian crater named for him. Many MarsWatchers had the good fortune of knowing him—a professional astronomer, powerhouse Mars observer, and strong supporter of pro-am collaborations. The crater is 70 km in diameter and is located at 6.57°N, 345.73°W. You can download a PDF map detail of the area. And here's a MarsView look centered on the area.

Happy New Year

Wed, 09 Jan 2008 02:13:36 EST

I've been enjoying basking in the glow of the Red Planet the nights, as well as seeing all the great images that keep pouring in! I'm also pondering what sort of observations may be in the works for the possible asteroid impact headed for Mars. Although recent updates put the odds back down to 1 in 28. Looking at the Mars Rover updates it seems that both of them are doing fine. It's getting into early autumn for them so they'll be busy trying to get as much science in before they need to rest up during the winter. Along with its geology duties, Spirit took out some time to send us another great panorama. You can really see the dust buildup no the solar panels! Mars Odyssey has been busy looking for sites to land the next rovers, the Mars Science Laboratory. The selection is down to 36 semi-finalists. Five finalists will eventually be chosen, but until then, check out the Themis observations of these sites. Some of them are even in and around Valles Marinaris, the Grand Canyon of Mars!

A bang in the new year?

Thu, 27 Dec 2007 01:10:46 EST

Life does get interesting! I take a week off to visit family over Christmas and come back to an e-mail message from MarsWatcher Jay Albert asking me if I'll be posting updates on this asteroid that might hit Mars next month. Well, before I can do any updates, I figure I'd better bring myself up to speed on this event. So, the asteroid in questions is one 2007 WD5, a member of the Earth-orbit crossing Apollo asteroids and it was only discovered this year on 30 November. The current best values for its orbital elements can be found at the NASA Near-Earth Asteroid site. Here's some of the highlights from their table:

Object	(2007 WD5)
Epoch	54200	Osculating epoch of the elements given as the modified Julian date (Julian date - 2400000.5) TDB
a (AU)	2.54137996	Semi-major axis of the orbit in AU
e	0.602518686	Eccentricity of the orbit
i (deg)	2.3713495	Inclination of the orbit with respect to the ecliptic plane and the equinox of J2000 (J2000-Ecliptic) in degrees
w (deg)	312.6459818	Argument of perihelion (J2000-Ecliptic) in degrees
Node (deg)	67.5399874	Longitude of the ascending node (J2000-Ecliptic) in degrees
M (deg)	313.3896583	Mean anomoly at epoch in degrees
q (AU)	1.0102	Perihelion distance of the orbit in AU
Q (AU)	4.07	Aphelion distance of the orbit in AU
P (yr)	4.05	Orbital period in Julian years
H (mag)	24.28	Absolute V-magnitude
MOID (AU)	0.032020	Minimum orbit intersection distance (the minimum distance between the osculating orbits of the NEO and the Earth)

You can see an up-to-date view of its orbit, relative to the orbits of Earth and Mars at the JPL Small-Body Database Browser site. Keep going back to see it update! According to the NASA Press Release from 21 December, there is a 1-in-75 chance that the asteroid will collide with Mars. The odds are based on the various uncertainties in the orbit of the asteroid due to the fact that it hasn't been known all that long. They say that if it collides, it'll leave a nice crater as it hits with the energy of about 3 megatons of TNT.

Closest approach!

Tue, 18 Dec 2007 05:25:26 EST

So today is the day we are closest to Mars—due to the severe ellipticity of Mars' orbit, this does not coincide with opposition (it would if both both Earth and Mars has circular orbits). As I write this, the actual time of closest approach is a little over an hour away (23:45 UT). I can hardly wait to see all the great images! The HST folks have already posted their contribution to the cause. It's a great image! NASA also recently released an image from Spirit showing some unusually white material. This was part of the MER overview given by Steve Squyres at the 39th Annual Division for Planetary Sciences meeting. He said that this stuff looks to be very rich in pure silica and there are really only two ways to make have this much here. The first is to have it dissolved into solution by a hot spring, then being deposited when the water goes away. The second is to have an acidic steam fumerole dissolve away everything but the silica. Either way, it's very interesting as we know that both such places here on Earth are usually teeming with life! This would be a great place to go to search for evidence of past life. Here's wishing everyone a happy winter-solstice-based holiday and clear skies from now through opposition on the 24th!

MRO looks at Mars' moons

Sun, 02 Dec 2007 09:34:28 EST

In the hustle and bustle of classes I seem to have let the entire month of November slip by without a post. Now that we're into the heart of the Mars opposition season I'll have pick up the pace. Last week NASA put out a press release showing some images of Phobos and Deimos as seen by the CRISM instrument on board Mars Reconnaissance Orbiter. Deimos, the smaller and farther-from-Mars of the two, was imaged this past June while Phobos was imaged in October. The press release discusses some differences of the two moons, and how they resemble asteroids made up of some of the most primitive stuff in the inner solar-system. Some of the initial studies of these data were presented at the FIRST INTERNATIONAL CONFERENCE ON THE EXPLORATION OF PHOBOS AND DEIMOS by Scott Murchie and coauthors. Their preliminary results so far tend to corroborate what has already been known—that they tend reflect more red and near-infrared light than blue (although, to the eye, they would appear mostly dark and gray), they they do not show any tell-tail signs of water or any of the dark, dense, minerals found in standard basalts (rocks similar to the dark areas of the moon and much of the bedrock of Mars itself). The geometry of the images will ultimately allow the team to study the differences in the less-red portion of Stickney crater on Phobos; the material is most likely impact ejecta which could be more, or less, primitive than the rest of the moon. I'll keep my eyes open for more of this work and report on it here as soon as I see it.

Observing is picking up

Tue, 16 Oct 2007 10:45:18 EDT

All last week I was at the Division for Planetary Science conference; I thought about blogging in semi-real time from there as sessions were going on, but decided I could better pass along what's going on in Mars research if I just took notes and then wrote it up more clearly later. I'll do that later this week. Last Sunday, just after getting back, I had to drive my wife to the airport at 4:30 am and as we walked outside, we looked up and saw Mars nice and bright in Gemini. I'm sad to say, it was my first sighting... I'm going to have to pull out my new telescope and start looking at it more closely! I don't have a camera adapter so I won't be posting any images myself. I had hoped to get time on the NASA Infrared Telescope Facility this year, but that fell through, so no images from their this year either. But I am really enjoying everyone else's submissions! So far we have about 265 submitted images, and the pace is picking up. Of course, this means that we are starting to get more members, and really putting the new system through its paces. There have only been a couple folks so far that have had issues with the system, and I thank them for their patience as we work out all the bugs. In general, I think this system is working far more smoothly than the old ftp submission system. Clear skies!

Anyone for Spelunking?

Wed, 26 Sep 2007 09:27:39 EDT

So it seems that the Mars Odyssey THEMIS team may have found openings to caves on Mars! They show up as really dark spot in visible images—dark because they have steep, nearly vertical, walls so no sunlight gets in at all from the fixed solar-viewing geometry of the orbiter. But that's not quite enough to convince anyone. The real clincher comes when you look at them in the thermal infrared (TIR). At these wavelengths, warm things are brighter than cold things. A cave tends to remain at a constant temperature (and roughly equal to the annual average local temperature of the area it is in). This means that a cave is colder than the local area in the day, but warmer at night. So in comparing images from the Odyssey THEMIS instrument that are in the visible band, the TIR in the day and the TIR at night, these cave entrances can be discerned: black in visible, dark TIR in the day, bright TIR at night. So, what's be big deal about caves? Well, they are relatively easy access to the underground where we figure any sort of life (if it exists on Mars) must have migrated in order to be shielded from the deadly UV and cosmic rays that bombard the surface. Of course, all the caves seen in this discovery are on the flanks for Arsia Mons, the southernmost of the three Tharsis Volcanoes. It seems unlikely that life would have migrated to these altitudes in the first place before having to go deep underground. But, if there are caves here, there may be caves elsewhere.

Rovers continue roving

Tue, 04 Sep 2007 08:41:59 EDT

According to the latest press release on Opportunity, the dust has cleared enough that they have taken the first steps to continue exploration. In fact, on 21 August Opportunity shuffled forward just over 13 meters towards Victoria Crater—remember, the goal is for the rover to work its way down into the crater. While there has been significant clearing, it could take months to be back to normal. Right now the rover is working on about half-power (which is double what it was getting just a few weeks ago!) so the rover team will be taking that into account as they move forward. You can see the gradual clearing throughout August and September in the MarsWatch image submissions. Thanks to all of you who make this possible! You can also compare it to the MRO maps from June and July. Spirit had recovered from the dust storm a little earlier than Opportunity, but it, too, is working at about half-power. Although the skies have begun clearing there's the issue of dust having settled on the solar panels. What we really need now is a good wind to blow it clear! There is also some question on what effect this settled dust will have on the instruments, especially the Mini-TES. As the spectrometer measures the thermal infrared light from targets, it could be corrupted by the light emitted from the dust on its optics making the job of identifying the target mineralogy much more difficult. The rover team has actually backtracked somewhat to image a target previously studied in order to get a feel for how this contamination will look.

More Phoenix and MER

Wed, 22 Aug 2007 10:03:59 EDT

OK, it's been awhile since I've posted anything here—I'll try to be better about that in the future. I'm finishing up all the grading involved with a 2-week intensive Space Science course I was doing for in-service middle-school teachers and that's been taking a lot of my time. However, as everyone probably already knows by now, the Mars Phoenix mission has successfully lifted off (4 AUG 2007) and is on its way. On 10 AUG 2007 it made its first course correction and all systems are still go. I have to admit that I'm really excited about this mission; the lander will be digging in the martian soil and running several life-searching experiments on what it scoops up. Depending on how deep they have to dig to find ices, they'll either dig up one long, deep trench or several shallower trenches. The lifetime of the mission is really going to be controlled by the onset of martian winter. Since Mars is tilted about 24 degrees, its north pole pointing at a spot about halfway between Deneb and ν Cephei, as it revolves around the Sun at some point it will be tilted away from the Sun and in seasonal darkness. Although during northern summer, the region where Phoenix will be will receive copious amounts of sunlight, once autumn begins, the Sun will begin getting very low to the southern horizon. Eventually the it will be too low in order to provide enough power to run the lander. After that it gets more interesting—the latitude where Phoenix will be is normally covered by the seasonal polar ice cap in winter! Earlier this month, JPL released a podcast discussing some of the science goals of Phoenix. It's a nice overview and was done by my friend and Mars colleague Leslie Tamppari. In Rover news, I hear that the teams are far more upbeat about the survival chances of both Spirit and Opportunity. In fact, Spirit has even been able to do some science as the skies begin to clear. While they're not out of danger completely, folks are optimistic. MRO continues to monitor the rover sites to get the birds-eye view of the area while the rovers themselves wake up long enough to snap a few pictures of the Sun to monitor cloud optical depth. We're all waiting for the dust to clear enough so the rovers can continue their missions.

Phoenix postponed

Tue, 31 Jul 2007 06:54:07 EDT

Just a quick note tonight: it seems as if Florida is going to be having some severe weather so the launch of the Phoenix mission (a redo with some extras of the Mars Polar Lander) is being postponed. It was originally planned to lift-off on 3 August, but there are still two more launch windows the next day. Here's hoping for clearing weather!

Rovers in the Dust

Tue, 24 Jul 2007 12:22:41 EDT

It figures, I go on vacation for a week, and that's when all the official news on the dust at the rover sites breaks! You can read the NASA PR report directly—it was updated on 23 July. In summary, it says that the dust in the area around Opportunity had thickened to the point where almost 99% of the sunlight is being blocked. It's almost as bad over at the Spirit site. The reason this is critical is that the rovers use sunlight to charge the battery packs that run them. When the output was cut in half, the teams suspended all activity (which means Opportunity's climb down into Victoria crater is on hold). As the storm worsened, the output was cut even further so communications were even cut back. Right now, the power output is just enough to keep the batteries charged to allow the rover to stay warm enough over night to stay alive. The latest communication seems to indicate that things are getting better, but the behavior of these dust storms is very hard to predict. For a while there, the rover had been gathering images of the local scene as the dust increased. NASA put together a composite image showing the darkening skies. Up at the top of the image you'll see the parameter τ which is the optical depth of the dust cloud and is a measure of the diminishing of the light. For the mathematically inclined, the light is dimmer by a factor of e^-τ, where e= 2.71828… is the exponential base. So, at τ=4.7, the light is at 0.62, or 62% of its nominal brightness. Mars Odyssey is still in orbit, going strong, and the THEMIS instrument (Thermal Emission Imaging Spectrometer) is measuring the atmospheric brightness as many wavelengths. With those data the team is able to model the atmospheric temperature as well as the dust cloud thickness. These results are being put into a daily map. Although the maps claim to be of dust opacity, the numbers on the scale make me believe they are really dust cloud optical depth—opacity is a sort of light-absorbing efficiency factor for a substance and optical depth is the total opacity along a path through the substance and thus a measure of the total light blocked. The maps have also been combined as frames in a nice animation. There are some major jumps early on, but once the storm takes off, you can see it evolve almost daily. Since we have Mars Reconnaissance Orbiter right there imaging the planet, we can see the visual effect of the storms in this mosaic. The decrease in regional contrast is stunning! This image is useful for giving you a visual reference for what those optical depth numbers "look" like. Of course, you can also keep an eye on the dust storms yourself, either through your own observing program, if you have a telescope (and if you make images, you can submit them here) or by visiting the MarsWatch images section and seeing what our army of observers is collecting. And let's all wish the rovers "clear skies"!

More Dust

Thu, 05 Jul 2007 10:13:19 EDT

There are more submitted images that have been posted here that show the current dust storm to be growing. It has now expanded southward to cover the south polar cap and northwest to obscure parts of Tyrrhenum and Cimmarium. It's hard to say how this is going to affect the Rovers at this point. Meridiani, where Opportunity is poised to descend into Victoria Crater, is not visible to USA based observers—here's hoping our eastern hemisphere contributors have clear skies! The storm is starting to close in on Spirit; if it does get there it will obscure the sunlight that is used to run and recharge the battery packs of the rover.

Opportunity APOD

Tue, 03 Jul 2007 08:56:26 EDT

So I'm checking out the Astronomy Picture of the Day (as I do every morning) and see this wonderful shot by Opportunity, one of the Mars Exploration Rovers. I thought this picture was stunning—it reminded me, somewhat, of the formations in Utah I'd visited back in 2005 right before the AAPT summer meeting (American Association of Physics Teachers). Although, the sky is just a bit too orange… The original MER catalog image tells us that it's Cape St. Vincent, one of the many promontories at the rim of Victoria Crater. The bright band of rock just a short way down the wall marks the boundary between a relatively loose jumble of rock and older bedrock—it was the "original" surface of Mars here before the impact. There's even a nice false color image that was made to better show the transition. Now that looks more like Utah! Opportunity has been spending some quite some time exploring the rim of Victoria Crater, a half-mile (800 m) wide impact feature. In fact, for the past 264 Sols (that's a martian day, which is about 30 minutes longer than a terrestrial day) it has traversed about a quarter of the way around, then come back. The reason: it was (in part) looking for a safe way down! That's right, the Rover team is going to send Opportunity down into Victoria crater. The main reason for going down is that "down" equals "back in time" so the deeper it goes, the older the rocks that it will be able to investigate. This will help fill in the picture of what Mars was like (at least in this area) through time and what the water availability was at those older times. This is some exciting geology! (Hmmm—I suppose that ought to be aereology , yes?) To get an idea of just what the rover is up against in its attempt to travel down into the crater, you can check out these 3-d images of the area it took. Since the rover cameras are about five feet above the ground, the depth perception you get from these images is about the same as you'd get if you were really standing there. You can also check out this flyover movie created by the US Geological Survey using MGS MOC images of the crater. And if you're looking for something truly spectacular, you can take a look at my favorite Victoria Crater image.

More Dust News

Thu, 28 Jun 2007 08:28:24 EDT

I got in today do review new image submissions and there was another image by Jim Melka showing dust spreading, now starting across Syrtis Major. There was also a dust alert put out by Richard McKim, Director of the British Astronomical Association Mars section:

Dear Mars Observer

On 2007 June 25 Jim Melka (USA) informed me about a dust storm spreading west from the northern Hellas basin across Noachis. The storm over Noachis was bright yellow, and in extent is typical of one already a few days old.

Images by Ed Lomeli (USA) on June 26 showed the event to have cut across Hellespontus in two places, and to have progressed as least as far as Argyre. As of June 27 the storm also now cut across Sinus Sabaeus in Lomeli's images, spilling into Aeria-Arabia, whilst Melka's image of yesterday shows that all of Hellas is full of dust, the original core being in the NW corner, and that activity is further developing or spilling over Ausonia-Hesperia to the east.

Both the timescale and nature of this development are entirely typical for Hellas events, and the seasonal date is also normal.

Any further observations of this event - which has now become Regional in status - are requested.

2007 June 28

No word yet on what sort of images of this storm have been made by any of the current suite of orbiters, but as soon as I hear anything, I'll post it here.

Dust Storm Alert

Tue, 26 Jun 2007 09:16:59 EDT

Mars observer Jim Melka has submitted an image from 25 June that shows a dust storm in the Noachis region that is occluding it and Mare Serpentis (these regions are just west of Hellas Basin). You can see that images by clicking on the Images link and setting the your search values for June 25; or you can follow this direct link. In the image, the south pole is at top and going straight down (north) from there you will see the round, orange, Hellas basin to the left (East) and another rounded orange spot down and to the right (northwest) of that—that's where the dark region Mare Serpentis ought to be. The dark area extending down and to the left (northeast) is, of course, Syrtis Major. The bluish-white band at the extreme north is, as Jim notes in his description, the North Polar Hood, a large cloud of ice that covers the northern polar cap. This region is well known for its dust storm activity. Back when the Mars Global Surveyor (MGS) was in its aerobraking phase, it imaged a dust storm in this region on 26 November 1997. It had started earlier, and by this point had expanded to quite the regional storm. By early December it had ended. Mars was too small too far away from Earth to be imaged well telescopically. In 2001, storms from this area whirled out and around Hellas Basin beginning in June and then turned into a global storm by early July. The dust loading in the atmosphere was measured by the MGS Thermal Emissions Spectrometer (TES). Since this was all happening shortly before the 2001 opposition, many folks from the IMW community were on top of it. You can see all the MarsWatch images from June and July that were submitted. Note: those pages are huge since they contain a full month of images—it was written before I had the idea of making sub-pages and I have not gone back to "fix" it. And again, in 2003, there were dust storms in Noachis. They were imaged by the MGS Mars Orbiter Camera on 14 August and 24 October. Once again, the MarsWatch regulars were monitoring it throughout the observing season. You can see their corresponding 13–16 August and October images for comparison. Note that due to the rotation of Mars, the areas viewed by MGS-MOC are not always facing Earth when ground-based observers can take their images. Finally, the MGS-TES team has compiled all their dust activity data into one big (35 MB) movie running from 9 April 1999 all the way to 31 August 2004. So now that we have a dust storm kicking around, we can only wait and see what comes of it. Clear skies!

Google Mars

Tue, 12 Jun 2007 05:52:10 EDT

I realize this is a bit old, but I ran across it again and realized that I'd never put in a link to it on any MarsWatch links pages—something I'll be fixing soon. So it seems that Google decided to put is powerful maps interface to work on various Mars data sets. If you go to www.google.com/mars you'll see their standard map interface with the Mars Global Surveyor Mars Orbiter Laser Altimeter (MGS-MOLA) elevation map. You can double-click on any region to center it, zoom in, zoom out, etc. It works just like their regular map interface, although no streets view or traffic reports. Aside from the elevation view, you can choose the visible or infrared views instead. The visible map is made from a mosaic of images taken with the MGS Mars Orbiter Camera (MOC). The zoom capability here is great! Just check out this view of the Olympus Mons caldera or this area of Candor Chasma. Really nice stuff. The infrared view comes from the Mars Odyssey Thermal Emission Imaging System (THEMIS). While it is mostly a greyscale image (bright = more IR emission, dark = less IR emission) the brown areas are places where they have added some very high resolution mosaics. To help you with your exploring, there are links that will highlight various features, spacecraft landing sites, and even NASA stories. About the only thing to be careful about is that when you are hand scrolling around, or you zoom out "too far", you see that the map is repeated several times—so, no, there really are not 4 Hellas Basins on Mars. Check it out and have fun doing your own "roving" on Mars! P.S. If you're interested, there's also a Google Moon.

Skylights on Mars

Tue, 29 May 2007 11:08:20 EDT

I was just getting ready to begin updates on the various spacecraft around and on Mars when this image of a hole on Mars showed up on the Astronomy Picture of the Day site. The absolute darkness of the region reminded me of those black dot bad pixels in older Viking images. However, it is rather clear that this black dot is much larger than a single pixel! The image was taken with the HiRISE camera on the Mars Reconnaisance Orbiter spacecraft and it appears to be the opening to a fairly deep cave. So deep that no sunlight reaches the bottom. The cave is located on the flank of the volcano Arsia Mons, the southernmost peak on the Tharsis plateau. It turns out, this feature is not unique. In a paper presented at the 38th Lunar and Planetary Science Conference this past March by scientists from the US Geological Survey, Northern Arizona University, and Arizona State University (G. E. Cushing, T. N. Titus, J. J. Wynne, and P. R. Christensen), have identified seven such regions that may be skylight entrances to deep, underground caves on Arsia Mons. In their paper they give several reasons for thinking these are cave entrances instead of just some really dark patch of ground. First, they are located in regions near collapse pits, indicating "open" underground regions. Second, they are not, themselves, collapse pits, or craters since they do not have visible floors/walls, nor do they have rims or the spray-pattern of debris associated with craters. Third is their thermal properties. See, these areas have also been images by the THEMIS instrument on Mars Odyssey which can measure the temperature of the martian surface. These dark areas are warmer than shadowed areas but cooler than the surrounding ground during the day, but warmer than the surrounding ground at night implying they are underground regions that keep a relatively constant temperature, much like caves here on Earth. What makes caves on Mars really interesting is that they would be "safe zones" for microbial life. Since the weak magnetic field and thin atmosphere allow all manner of UV and high-energy cosmic ray radiation to hit the surface, all life as we know it would be killed off rather quickly. Deep caves would block all of that radiation; and these skylights present ways into these underground caves. Time to send in the spelunkers! Any takers?

2007 MarsWatch up and running

Fri, 18 May 2007 08:42:03 EDT

Welcome to the new and improved International MarsWatch! After years of running this site, I finally realized that I needed the help of someone with far better web skills than I. Fortunately, there is considerable talent in the students at Rowan's Computer Science department, and so we now have this brand new site. Oh, if you don't like the color scheme, blame me—that was all my doing. I'm not entirely sure I like it yet, but we'll see. Supposedly changing that will not be overly difficult. The project started with trying to create a way to make image submission easier. Most images were uploaded the last time around via e-mail submissions directly to me. It was great being the first to see them, but as the season progressed, it became time consuming to handle it all. The solution designed was great, but required other changes, which required other changes… This new site now has an automated image submission system. Members can upload images, and even include a text description should they like (it should even handle "international" characters correctly). There is still a review process I'll have to go through, just to keep any "inappropriate" images from showing up here. The rest of the site features have been ported over including the MarsView program, basic opposition information, Mars-related links, and the Newsletter archive. Just poke around through the links in the left-hand menu. The biggest change is this blog. Instead of trying to put out a monthly newsletter with some of the latest Mars info and news, I will be doing entries here once or twice a week. This way, the news will be more current, and I can even use this area to review some of the current Mars research from the scientific journals. I'll still try to send out a Newsletter, but it will be devoted to Mars ephemerides, and a summary of, say, the last few blog entries. One other thing I'd like to do here is help maintain the bridge between the amateur and professional Mars observers. As the professionals get their observing time awards, it would be nice if they'd pass them along so that others can perform coordinated observations. Once again, the goal of the MarsWatch is planet-wide imaging throughout the opposition.