Just came across this photo on Twitpic, courtesy of @Astro_Wheels (astronaut Douglas H. Wheelock) and @mars-stu (Stuart Atkinson) on Twitter, although posted back on September 26. Not specifically planetary related as such, but as others have mentioned, it is a beautiful shot; astronaut Tracy Caldwell Dyson is watching the Earth below, from inside the new cupola on the International Space Station. A contemplative view of our own planet…
I’ve updated the blogroll listing again. If you know of a good blog that is missing, please let me know. Please note that I’m keeping this listing to blogs that are directly or at least partially related to planetary exploration. Thanks!
The Mars rover Opportunity continues its long journey across the flat plains of Meridiani, coming ever closer to its next major destination, the huge Endeavour crater, which is still several months away. In the meantime though, here are some nice views of Intrepid crater, which is much, much smaller but still interesting of course.
Additional images (raw) are here. In some, portions of Endeavour’s rim can be seen on the horizon. While Intrepid is only a matter of metres wide, Endeavour is about 22 kilometres (14 miles) across. The edges of its rim are more like mountains. Before we get there, there is also Santa Maria crater along the way, significantly larger than Intrepid, but still much smaller than Endeavour. This region near Endeavour is very flat and featureless for the most part, so not much to see otherwise, but once we get there, the views will be amazing.
The Deep Impact spacecraft successfully completed its second cometary encounter earlier today, this time a close flyby of comet Hartley 2, and has returned some amazing images. The icy jets of gas and dust are very prominent in the new photos. See also the image gallery here. This is the fifth comet to be visited by a spacecraft.
There are already various nicknames for the comet after these first-ever close-up images, including dog bone, peanut, drumstick, cigar, bowling pin and pickle (I like dog bone and peanut the best). A question others have also been asking – why is the central part like a smooth-looking band, while the two ends are bumpy and rocky?
Two more pieces of the water-on-Mars puzzle in the last few days… the Mars rover Spirit has found new evidence of liquid water having trickled down into the soil in the relatively recent past, while the Mars Reconnaissance Orbiter has found an old volcanic cone which would have been warm and wet even after most of Mars had already started to change to the cold, dry place we see today.
When Spirit became stuck in the sand last year, the wheels churned up the soil during extraction attempts, which turned out to be a blessing in disguise. The revealed layers below the surface indicated that small amounts of water, perhaps from frost or snow, trickled down into the soil, likely sometime within the last few hundreds of thousands of years (recently, geologically-speaking) and on an on-going basis. See also the published paper here.
Meanwhile, the deposits of hydrated silica on an old volcanic cone in Nili Patera, photographed by the Mars Reconnaissance Orbiter, are thought to be the best evidence yet for ancient hydrothermal vents (fumaroles or hot springs). On Earth, such places are prime areas of habitability for microbes. They would also have been habitable places on Mars, but were they actually inhabited? The deposits are similar to ones found at hydrothermal vents in Iceland. The Mars rover Spirit had also previously found similar deposits directly in the soil (another tie-in to the other findings discussed above), evidence that fumaroles or hot springs were once present at its landing site.