Gusev crater
The crater is 3 km in diameter and its age is estimated to be 49.0 ± 0.2 million years old placing it in the Eocene. The crater is not exposed at the surface. It may have formed at the same time as nearby and larger Kamensk crater.
Gusev Crater is a crater on the planet Mars and is located at 175.4°E 14.6°S. The crater is about 170 kilometers in diameter and formed approximately three to four billion years ago. It was named after Russian astronomer Matvei Gusev (1826–1866) in 1876.
A channel system named Ma'adim Vallis drains into it that probably carried liquid water, or water and ice, at some point in Mars' past. The crater appears to be an old crater lake bed, filled with sediments up to 3000 feet thick. Some exposed outcrops appear to show faint layering, and some researchers also believe that landforms visible in images of the mouth of Ma'adim Vallis where it enters Gusev Crater resemble landforms seen in some terrestrial river deltas. Deltas of this nature can take tens or hundreds of thousands of years to form on Earth, suggesting that the water flows may have lasted for long periods. Orbital images indicate that there may once have been a very large lake near the source of Ma'adim Vallis that could have provided the source of this water. It is not known whether this flow was slow and continuous, punctuated by sporadic large outbursts, or some combination of these patterns.
Panoramic photo taken by Spirit Rover on January 1, 2006 from Gusev Crater, looking up a slope and across rippled sand deposits in a dark field dubbed "El Dorado".
Panoramic photo taken by Spirit Rover on January 1, 2006 from Gusev Crater, looking up a slope and across rippled sand deposits in a dark field dubbed "El Dorado".
More recently, satellite images showed the trails of dust devils on Gusev Crater's floor. The Spirit rover later photographed dust devils from the ground, and likely owes much of its longevity to dust devils cleaning its solar panels.
On January 3, 2004, Gusev Crater was the landing site of the first rover in NASA's two Mars Exploration Rovers, named Spirit. It is hoped that the numerous smaller and more recent craters in this region will have exposed sedimentary material from early eras, although at first the region proved disappointing in its lack of available bedrock for study on the flat lava plains of the crater, Spirit's landing site. She eventually arrived at the Columbia Hills, however, and rocks examined in that region show that the Columbia Hills did have small amounts of briny (salty) water interacting with them in ancient times,[1] though nowhere near as much as Meridiani Planum, the landing area for Spirit's twin
A 144-km-wide (90-mile) crater, located just south of the equator of Mars, that is the landing site for Spirit, one of the Mars Exploration Rovers. Gusev Crater appears to have been formed by the impact of an asteroid some three to four billion years ago. A channel system, known as Ma'adim Vallis, which probably carried liquid water, or water and ice, drains into the crater, implying that the structure almost certainly once contained a lake. Inside the crater, researchers expect to find sediments, which may be nearly 3,000 feet thick, that have subsequently been overlaid by dust and sand. The Spirit rover will be able to grind away the surface cover on rocks and analyze minerals inside and it will be able to view its surroundings with unprecedented detail and precision. One clear sign of past water will be in the rocks. For example, if Gusev did indeed once hold a giant lake (more than 10 times the size of the famous Crater Lake in the United States) certain key minerals are likely to be found in its rocks.
Gusev Crater and surrounding region
Gusev Crater and surrounding region. The white mark indicates the landing ellipse for the Spirit rover.
Spirit might find evaporites – minerals formed as water dries up. Salt or gypsum are familiar ones here on Earth. Salt’s component parts – sodium and chloride – are separated, dissolved in sea water, but as the water dries up, the sodium and chloride join together to form the mineral halite. On Mars, Spirit might find evaporites like gypsum, or calcium magnesium sulfate. It might also find minerals involving carbonates (e.g., calcium carbonate). These are sometimes, although not always, produced by or from living organisms. But they are almost always a sign of water when found on Earth. Another sign will be in the way the sediments are organized. For example, if the sediments were blown in by winds, the layers may be more erratic, to reflect the changing directions of airflow (as in fossil dunes here on Earth). If they were deposited by water, they are more likely to be layered evenly, one on top of the other in rhythmic stacks. The most exciting result Spirit might find is that liquid water existed at the surface of this site for a long time because persistent standing bodies of water are possible habitats for life.