Parts of Mars used to be Earth-like | Ars Technica
One of the joys of geology is painting a picture of a different world-a long-ago world otherwise completely lost to us. If you’re a planetary geologist, you have the chance to pull off that trick with a properly different world, one not currently named Earth. Courtesy of Curiosity, the robotic geologist currently exploring Mars, we have a new picture of the history of the crater the rover is roving in.
Gale Crater was excavated by an impact event roughly 3.7 billion years ago. Rising over five kilometers from the floor of the crater is Mount Sharp (officially Aeolis Mons). How’d it get there? That question is, in a way, interesting enough that we went there to find out.
After landing safely on the plain surrounding Mount Sharp, Curiosity has made its way to the base of the mountain, stopping to smell the rocks along the way. Climbing Mount Sharp takes the rover on a trip through martian history, as the mountain is basically a layer cake of sedimentary rock. A new study published this week by 47 researchers back on Earth focuses on what we’ve seen so far in the two layers at the base of the cake.
In the lower part of the basal layer, there are sandstones as well as some gravelly layers. The sandstones show a pattern called “cross-bedding”-repeated diagonal lines between the top and bottom of a layer. These are the remains of crawling ripples or dunes. In this case they are short ripples deposited by something flowing toward the center of the crater. Together with the presence of the gravels, this points to the action of streams.
The flowing water kind...
Parts of Mars used to be Earth-like | Ars Technica
Gale Crater was excavated by an impact event roughly 3.7 billion years ago. Rising over five kilometers from the floor of the crater is Mount Sharp (officially Aeolis Mons). How’d it get there? That question is, in a way, interesting enough that we went there to find out.
After landing safely on the plain surrounding Mount Sharp, Curiosity has made its way to the base of the mountain, stopping to smell the rocks along the way. Climbing Mount Sharp takes the rover on a trip through martian history, as the mountain is basically a layer cake of sedimentary rock. A new study published this week by 47 researchers back on Earth focuses on what we’ve seen so far in the two layers at the base of the cake.
In the lower part of the basal layer, there are sandstones as well as some gravelly layers. The sandstones show a pattern called “cross-bedding”-repeated diagonal lines between the top and bottom of a layer. These are the remains of crawling ripples or dunes. In this case they are short ripples deposited by something flowing toward the center of the crater. Together with the presence of the gravels, this points to the action of streams.
The flowing water kind...
Parts of Mars used to be Earth-like | Ars Technica