Categories: Mars

Odyssey Serves Up Canyon Images

Image credit: NASA

Now in its final orbit, Mars Odyssey is getting to work searching for water on the surface of the planet. The most recent set of images returned are of a network of channels taken by the Thermal Emission Imaging System (THEMIS). The Nirgal Vallis is a channel 500 km long and 6 km wide at this point – astronomers believe that gullies on the side of the channel were formed when water erupted to the surface.

This THEMIS image shows a sinuous valley network channel with sharp bends cutting across the cratered highlands of the southern hemisphere of Mars. The channel is named Nirgal Vallis, which is from the Babylonian word for “Mars”. Nirgal Vallis is a channel with a total length of approximately 500 km. It is approximately 6 km wide in this region. Gullies and alluvial deposits discovered by Mars Global Surveyor are clearly visible on the polar-facing (south) wall and floor of Nirgal Vallis. These gullies appear to emanate from a specific layer in the walls. There is a pronounced sparsity of gullies on the equator-ward facing slopes. The gullies have been proposed to have formed by the subsurface release of water. Patches of dunes are also seen on the channel floor, notably along the edges of the channel floor near the canyon walls. There is still debate within the scientific community as to how valley networks themselves form: surface runoff (rainfall/snowmelt) or headward erosion via groundwater sapping. This image is approximately 22 km wide and 60 km in length; north is toward the top.

Original Source: ASU News Release

Fraser Cain

Fraser Cain is the publisher of Universe Today. He's also the co-host of Astronomy Cast with Dr. Pamela Gay. Here's a link to my Mastodon account.

Recent Posts

The Last Arecibo Message Celebrates the Observatory and One of its Greatest Accomplishments

The Arecibo Message, transmitted on November 16th, 1974, from the Arecibo Observatory, was humanity's first…

5 hours ago

A Nearby Supernova Could Finally Reveal Mark Matter

Despite 90 years of research, the nature and influence of Dark Matter continue to elude…

6 hours ago

Astronomers Find a 3 Million Year Old Planet

Astronomers have just found one of the youngest planets ever. At only 3 million years…

1 day ago

There was Hot Water on Mars 4.45 Billion Years Ago

Mars formed 4.5 billion years ago, roughly the same time as the Earth. We know…

1 day ago

Axion Dark Matter May Make Spacetime Ring

Dark matter made out of axions may have the power to make space-time ring like…

2 days ago

Earth’s Old Trees Keep A Record of Powerful Solar Storms

Most of the time the Sun is pretty well-mannered, but occasionally it's downright unruly. It…

2 days ago