Now that Curiosity has landed, where did it land? Well, first and most obviously, it landed in a five billion-year-old meteor impact crater named Gale Crater. Gale Crater was, for a time, filled with sand and rock, but then wind and water eroded much of that sand and rock away, leaving as residue a mountain of sediment taller than Mount Wilson in California and akin to the Grand Canyon: it reveals, in distinct geological layers, Mars’ evolutionary history. That mountain of sediment has been dubbed Mount Sharp.
Curiosity has also landed, fortuitously, in an alluvial fan. That’s big news, for it’s the first thing to watch for news about in the coming weeks. Here’s the Los Angeles Times today:
Curiosity landed in a geological feature called an alluvial fan, a plain of rocks and dirt likely deposited by a river during Mars’ ancient, watery past. When it comes to Curiosity’s primary mission, the search for evidence that Mars is or was able to foster life, the fan could be “a jackpot,” said Caltech geologist John Grotzinger, the mission’s lead scientist.
The second big thing to watch for is what Curiosity discovers at Mount Sharp:
The ultimate target, and the reason Gale Crater was selected as a landing zone, is the towering and unusual mountain in the center of the crater. Known as Mt. Sharp, it is taller than any in the Lower 48 United States, and scientists believe its walls were eroded over millions of years, either by wind or water, and contain a preserved record of Mars’ history and evolution.
It’s an exciting time to be alive.