In the first full day of the annual meeting of the Division of Planetary Sciences of the American Astronomical Society, I listened to scientific sessions on icy worlds and on an exoplanet in a four-star system.
Long-runout landslides (sturzstroms) are found across the Solar System. They have been observed primarily on Earth and Mars, but also on Venus, and Jupiter’s moons Io and Callisto. I have just published a paper about sturzstroms on Iapetus.
I'm hosting this week's Cosmoquest Science Hour, and plan to take viewers on a virtual tour of those mountains on Curiosity's horizon, and show you where Curiosity is likely to go. Join me and Fraser Cain here at 1600 PDT / 2300 UTC Wednesday.
Some notes from this morning's Curiosity press briefing: the rover will be driving to "Glenelg" to investigate the "high thermal inertia unit." I explain what that means, with psychedelic Odyssey THEMIS images of the landing site.
Water ice at Mercury's poles? That's crazy, right? Mercury is so close to the Sun that it seems inconceivable that you could have water ice there. But Mercury's rotational axis has virtually no tilt (MESSENGER has measured its tilt to be less than 1 degree), so there are areas at Mercury's poles, most often (but not always) within polar craters, where the Sun never rises above the horizon to heat the surface.
There's been a bit of buzz on the Web this week regarding an ESA press release titled "ESA's Mars Express radar gives strong evidence for former Mars ocean." I don't ordinarily write about press-released science papers, but am making an exception for this one.
Evaporites form on planetary surfaces when dissolved chemical solids precipitate out of saturated solution as their liquid solvent evaporates and, until recently, were known to exist only on Earth and Mars. This article from the IAG Planetary Geomorphology Working Group describes the third planetary instance of evaporite, discovered on Saturn's moon Titan.
The Google Doodle for January 11, 2012 celebrates Nicholas Steno, one of the founding fathers of modern geology, on the occasion of his 374th birthday. This article describes Steno's set of rules that guide geologists in reading rocks to tell the story of how a place came to be and how the rules are currently used in geology.
Among Europa scientists there are two warring factions: the thick-icers and the thin-icers. The question is how thick is the ice shell that overlies Europa's subsurface ocean (the existence of which pretty much everyone agrees on).
Today they turned on the scientific fire hose at the Division of Planetary Sciences / European Planetary Science Congress meeting happening here in Nantes, France. My brain already feels full and I still have four more days!
About four years ago I wrote a blog entry about an ESA press release about paper published in Nature that suggested that Saturn's moons Tethys and Dione might have volcanic activity, like Enceladus. A new paper published in Icarus casts doubt on that conclusion.
When Hayabusa's sample return capsule was first opened and found to be very clean-looking inside, I doubted that there could be enough material for laboratory analysis. JAXA announced later that they scraped about 1500 dust grains from the inside with a teflon spatula, and these likely came from Itokawa.