Category Archives: Mars

Welcome to a Martian Landscape

Mars Express Images a Valley on Mars

A Mars Express image of a region near Maadim vallis, one of the largest canyons on Mars. Courtesy European Space Agency. (Click to embiggen.)
A Mars Express 3D "ortho-image" of a region near Ma'adim vallis, one of the largest canyons on Mars. Courtesy European Space Agency. (Click to embiggen.)

It’s a great day in the solar system — there are telescopes aimed at Jupiter to follow the aftermath of the recent collision into the southern polar region; instruments are monitoring solar activity, Cassini continues to show us the wonders of the Saturn system, Mercury is still being mapped, the Moon is under heavy study, and the news and images from landers and mappers at Mars continues to flow our way.  Now, if we just had PEOPLE on Mars!  Well, when the first Marsnauts DO get there, they’ll have great images like this one from Mars Express to study.

Where is this place? It’s near one of the largest canyons on Mars — a giant rift called Ma’adim Vallis. This area lies between the Tharsis volcanic region of Tharsis (and its four large volcanoes) and the Hellas Planitia impact basin.

There’s quite a lot of interesting terrain here and a little planetary science interpretation tells an interesting story. The canyon itself is 20 kilometers wide and 2 kilometers deep. It begins in the southern highlands close to the a region called the “dichotomy boundary” that divides the cratered highlands on Mars and the nearby lowland plains. The canyon ends in Gusev crater, where the Spirit Rover is currently exploring.

The region near Maadim Vallis, as seen by Mars Express. (Click to embiggen.)
The region near Ma'adim Vallis, as seen by Mars Express. (Click to embiggen.)

The image you see here covers a region of Mars about the size of the island of Cyprus on Earth.  There’s a sharp boundary is visible that divides dark material to the west and light material to the east. This probably the edge of a basaltic lava flow. Wrinkle ridges are clearly visible on the surface of the lava flow and they probably formed as the rock was compressed by tectonic action after the lava was laid down.

The crater in the north part of the image is about 20 kilometers across and seems to be partly filled with lava deposits that flowed in after the crater formed.  The smaller crater at the southern edge of the larger crater must have formed later because it has an ejecta blanket that may have formed from material rich in water ice that was blasted out during the impact.

A 200-kilometer-long linear feature divides the image almost in half. This is probably a trough that formed when the Tharsis volcanic region was active. That activity caused the whole area to “lift up” — and that had to have created a lot of stress in the crust.  The typical way that surface crusts deal with stress is to break into pieces. Hence, you get fracture zones, and the creation of troughs and other broken terrain like you see here.

Images like these are fascinating for a lot of reasons. First, they’re another world — one that we’re learning a LOT about as our robot explorers send back more images and data. Second, they’re from a world that we hope humans will visit very soon. Third, those regions look so very familiar because we see places like them on Earth — and we know how they formed on Earth, so that helps us understand how they work on Mars. Finally, they’re just darned cool!  Not a very scientific-sounding reason, but hey — science IS cool.  And so is studying other planets!

Slip-slidin’ on Mars

Spirit Digs in its Wheels

https://i0.wp.com/marsrovers.jpl.nasa.gov/gallery/press/spirit/20090511a/SolA1899_hazcam_2F294958090EFFB1DNP1254L0M1_br.jpg?resize=250%2C250
The view of soft, thick soil underneath the Spirit Rover on Mars -- taken with the front haz-cam on Sol 1899. Courtesy NASA/JPL-CalTech. Click to embiggen.

The Spirit Rover on Mars is really digging itself into the surface these days. And I mean in a worrisome way.  It’s five working wheels are slipping severely in the very soft soil it now finds itself on and the wheels are dug in about halfway.  Or, think of it as being stuck up to the mudflaps. The situation is bad enough that the handlers and scientists have stopped trying to drive the rover around until they can figure out a safe way to keep things moving.

However, that doesn’t mean the science has stopped. The soft plushy soil that is dragging Spirit down gives scientists a great opportunity to learn more about the physical characteristics of that soil. They’ll focus the attention of some of the instruments onboard the Rover to the task. Luckily, the Martian winds have been scouring Spirit’s solar panels clean, so it can generate more power for the instruments.

While Spirit is doing soil testing and analysis, the scientists and engineers will do some testing of their own at JPL. Simulation tests with the Earth-bound rover counterpart will show them how and when they will be able extricate Spirit from its Martian sandbox to resume its journey across Gusev Crater.