This image shows the rock called "Souffle".
Click on image for full size
Image from: NASA/JPL
Martian Surface Winds
The surface pressure of Mars is about 1/150th that of the surface pressure of the Earth. This means that there are much fewer molecules in the atmosphere. This means that the atmosphere near the surface of Mars has much less inertia than that near the surface of the the Earth. Putting the atmosphere of the Earth in motion must be like putting molasses in motion compared to putting the atmosphere of Mars in motion. This means that the Martian surface winds can be accelerated to higher speeds than those on Earth, see the classes of terrestrial wind speeds. The general circulation pattern of winds is also very different from the terrestrial circulation pattern. These winds can be whipped to an extreme during the frequent Martian global dust storms.
Because of Mars' lower gravity, the winds can more easily lift and carry sand particles. Sand particles from the surface driven by winds contribute to sand erosion of the surface. Features found by the Mars Pathfinder lander provided plenty of evidence for sand erosion by wind. But the lower atmospheric pressure of Mars makes it harder for the winds to impart momentum to sand particles lying on the ground. Thus the amount of sand grains lifted from the surface are accelerated to high speeds may be different from what would be expected on the Earth. This makes the erosion of Martian rock a little different than on Earth.
The first weather measurements made from the surface of Mars were performed by the Mars Pathfinder mission. These measurements provided some "ground truth" for the strength of Martian winds.
Shop Windows to the Universe Science Store!
Our
online store includes
issues of NESTA's quarterly journal, The Earth Scientist, full of classroom activities on different topics in Earth and space science, ranging from
seismology,
rocks and minerals,
oceanography, and
Earth system science to
astronomy!
You might also be interested in:
Dried debris left after a flood is "wind mobile" and can be lifted into the air by winds. The general process by which this occurs is called "saltation". Saltation is the primary form of abrasion and erosion
...more
There are two main weathering agents on Mars: wind and acid fog. Although acid fog can be very important, because large amounts of water are not readily accessible from the Martian surface, the action
...more
This is the first image showing clouds of Mars taken from the lander. Ground based viewing of Mars has shown that clouds seem to be plentiful only in the middle latitudes This may be because water of Mars
...more
This is image of a Martian sunset illustrates just how thin the Martian atmosphere is. The terrestrial "blue sky" comes about because molecules of the atmosphere scatter sunlight. In this image, the Martian
...moreThe surface pressure of Mars is about 1/150th that of the surface pressure of the Earth. This means that there are much fewer molecules in the atmosphere. This means that the atmosphere near the surface
...more
Mars is much like Venus-- it's very bright and therefore easily spotted in the night sky. Because of this, we don't know who exactly discovered Mars. We do know it was named after the Roman god of war,
...more
If approved, the Mars 2003 mission will have two important parts. The first is the Mars Surveyor 2003 Lander, which will be launched sometime between May 27, 2003, and June 17, 2003. The lander will use
...more
This image of a potential landing site for the Mars '98 mission was provided by the Mars Global Surveyor mission. The landing site was suppose to be in the south polar region of Mars. In the image, ground
...more
