Really cool movies from Jim Richardson propose to explain how the same physics of impact cratering can produce such differently-appearing surfaces as those of the Moon, large asteroids like Eros, and teeny ones like Itokawa.
When Mariner 10 flew past Mercury, it caught an immense impact basin lying half in and half out of sunlight, which they named Caloris. Even with only half the basin visible, scientists knew it was one of the largest in the solar system. Geologists had to wait more than 25 years to see the rest of Caloris, and when they did it turned out to be even bigger than they had thought. But the fact that Caloris was only half in sunlight was fortuitous in one sense, because it meant that the spot on Mercury that was exactly opposite the area of the Caloris impact was also partially in sunlight. That spot looks weird.
Kirby Runyon, a second-year grad student at Temple University, offered to send me some writeups of selected presentations from last week's Lunar and Planetary Science Conference, and I enthusiastically agreed.
I've spent the day noodling around in the current issue of Icarus, following up some of the more interesting stories within its table of contents, and came across a picture of this very cool crater -- actually, set of craters -- on Mars.
In the last few days, Opportunity's passed by several craters, and the rover drivers took advantage of the chance encounters for what they call "drive-by shooting" (a phrase I can't say I'm particularly fond of, but they didn't ask me).
There has been big news from Moon and Mars here at the Lunar and Planetary Science Conference, but I can't find the time to wrap that stuff up into a properly illustrated blog post; while I'm still on site at the conference I'll be tossing the easier-to-digest bits into the blog.
It was January of 2004 when the elegant curve of the Vichada first caught the attention of geologist Max Rocca of Buenos Aires. Could the course of the river have been shaped by the circular outlines of an impact crater? Rocca decided to find out.
It looks like the rover team thinks Concepcion is pretty enough (in both aesthetic and a scientific senses) to be worthy of the full-color Pancam panorama treatment; color frames started arriving on Earth over the weekend.
Since leaving Marquette Island on sol 2,122, Opportunity has been barreling southward on her journey toward Endeavour crater. On her horizon for the last several sols has been a very small but very fresh looking crater named Concepción.