Wow. You've got to check out these amazing new images from Saturn.

Yet another tip o' the hat to Diego H. for passing this link on to me...

Labels: astronomy, planetary geology, satellite imagery

Every now and again, I like to post an image that just speaks volumes. Check this one out, of Saturn's moon Enceladus. Wow! What a beauty. This photograph was taken on Monday by the Cassini spacecraft. Enceladus may host liquid water below the surface, since it has geyser-like features near its south pole. There are only three places beyond the asteroid belt where eruptions have been seen: Enceladus, the jovian moon Io, and Neptune's moon Triton. Enceladus is only a few hundred miles wide; These fractures are about 1000 feet deep.

Labels: art, planetary geology

Mars has a new robot geologist on its surface, as of last night at just before 8pm (E.S.T.). The Mars Phoenix lander arrived in Mars' north polar region after an apparently dicey landing sequence that went off without a hitch. It unfurled its solar panels and started taking pictures, like the one at the left. That's a new view of the planet thought most likely to give us insights into the possibility of life elsewhere in the universe.

Why the pole? That's where the water is. Remote sensing indicates ice just a few inches below the surface in this area, and the geomorphology seems to back that up. Visible even in this earliest photo, polygonal shaped features suggest repeated freeze-thaw action. (Similar freze-thaw action in Earth's polar regions produces similar features, like these:



That's the way geology works, right? The principle of uniformity suggests that uniform physical laws operating over vast ranges of time and space will produce similar phenomena in different locations. It remains to be seen how valid this principle is in guiding our exploration of other planets, but with Mars it appears that there are some real similarities. And why do we care where the water is? Because on Earth, all life needs water. Figuring out whether life exists elsewhere in the universe has huge implications for our place in the cosmos.

Labels: mars, planetary geology, satellite imagery, tech

Check out yesterday's excellent post by Geotripper about the recent arrival at Earth of light from a supernova that happened 7.5 billion years ago.

Labels: blogs, planetary geology

So, this is weird: a new insight into the planet Mercury is that it has a big long tail which extends away from the planet, strung outwards by the solar wind (a stream of charged particles shooting away from the Sun in every direction). Comet tails are also due to the solar wind's erosive effect, vaporizing particles & dragging them "down-stream" (i.e., away from the Sun). The tail is long: At 1.6-million miles in length, the streamer of sodium atoms is more than 100 times the planet's radius. Read more here.

Labels: news, planetary geology

I was struck by the visual similarity of these two round graphics from the Science section of today's Washington Post. The first shows the circuitous path taken by the Mercury Messenger spacecraft, which is scheduled to fly by the innermost planet in about 2 hours from the time I'm writing this:


The second image shows the changing ice situation in Antarctica on a cool combination of ice-flow velocity map and ice loss/gain bar graph, wrapped around the edge:

Labels: art, global warming, planetary geology