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.

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.

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.

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.

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.