Eberswalde (crater)
Encyclopedia
Eberswalde, formerly known as Holden
NE, is a partially buried impact crater
in Margaritifer Terra
, Mars
. Eberswalde Crater lies just to the north of Holden Crater
, a large crater that may have been a lake. The 65.3-km-diameter crater, centered at 24°S, 33°W, is named after the German
town of the same name
, in accordance with the International Astronomical Union
's rules for planetary nomenclature. It was one of the final four proposed landing sites for the Mars rover Mars Science Laboratory
mission.
Landforms in the crater provide strong evidence of the prior existence of flowing water on Mars.
have been proposed as areas to send NASA's next major Mars rover, the Mars Science Laboratory (MSL). Eberswalde Crater was shortlisted as one of the final four proposed landing sites for the Curiosity rover, part of the MSL mission. It was voted a close second after Gale Crater by a team of scientists.
MRO
discovered iron/magnesium smectites here. This mineral requires water to form.
formed by the flow of a liquid, most likely water. The series of valleys leading into the delta "drain
" an area of approximately 4000 km². The surface area of the delta is 115 km², measuring 13 km by 11 km. The delta was discovered by Michael Malin and Kenneth Edgett of Malin Space Science Systems
through imagery taken by the Mars Global Surveyor
in 2003.
The delta also provides unambiguous evidence that some Martian sedimentary rocks have been deposited in a liquid. The meandering of the channels provides evidence to support this. Additional sediments were deposited on top of the delta, burying it. The deposits in the channels formed sedimentary rock. As the surrounding softer sediments were eroded away, the delta was exhumed, but inverted.
Based on an estimate by Moore et al. in 2003 of flow volume to the crater at 700 m3/s, it is estimated that it would take twenty years to completely fill the crater, ignoring evaporation
and infiltration
. However, this is unlikely because it is hypothesized that the delta was not formed in a permanent lake but rather a series of short lacustrine
episodes on the order of years. This suggests that the Martian climate at the Noachian epoch time of formation was characterized by a series of short, wet spells rather than a sustained wet climate.
Holden (Martian crater)
Holden is a 140 km wide crater on Mars, located with the southern highlands. It is named after Edward Singleton Holden, an American astronomer, and the founder of the Astronomical Society of the Pacific....
NE, is a partially buried impact crater
Impact crater
In the broadest sense, the term impact crater can be applied to any depression, natural or manmade, resulting from the high velocity impact of a projectile with a larger body...
in Margaritifer Terra
Margaritifer Terra
Margaritifer Terra is an ancient, heavily cratered region of Mars. It is centered just south of the Martian equator at and covers 2600 km at its widest extent. The area reveals "chaos terrain", outflow channels, and alluvial plains that are indicative of massive flooding. Wind erosion patterns are...
, Mars
Mars
Mars is the fourth planet from the Sun in the Solar System. The planet is named after the Roman god of war, Mars. It is often described as the "Red Planet", as the iron oxide prevalent on its surface gives it a reddish appearance...
. Eberswalde Crater lies just to the north of Holden Crater
Holden (Martian crater)
Holden is a 140 km wide crater on Mars, located with the southern highlands. It is named after Edward Singleton Holden, an American astronomer, and the founder of the Astronomical Society of the Pacific....
, a large crater that may have been a lake. The 65.3-km-diameter crater, centered at 24°S, 33°W, is named after the German
Germany
Germany , officially the Federal Republic of Germany , is a federal parliamentary republic in Europe. The country consists of 16 states while the capital and largest city is Berlin. Germany covers an area of 357,021 km2 and has a largely temperate seasonal climate...
town of the same name
Eberswalde
Eberswalde is a major town and the administrative seat of the district Barnim in the German Federal State of Brandenburg, about 50 km northeast of Berlin. Population 42144 , geographical location . The town is often called Waldstadt , because of the large forests around it, including the...
, in accordance with the International Astronomical Union
International Astronomical Union
The International Astronomical Union IAU is a collection of professional astronomers, at the Ph.D. level and beyond, active in professional research and education in astronomy...
's rules for planetary nomenclature. It was one of the final four proposed landing sites for the Mars rover Mars Science Laboratory
Mars Science Laboratory
The Mars Science Laboratory is a National Aeronautics and Space Administration mission with the aim to land and operate a rover named Curiosity on the surface of Mars. The MSL was launched November 26, 2011, at 10:02 EST and is scheduled to land on Mars at Gale Crater between August 6 and 20, 2012...
mission.
Landforms in the crater provide strong evidence of the prior existence of flowing water on Mars.
Mars Science Laboratory
Several sites in the Margaritifer Sinus quadrangleMargaritifer Sinus quadrangle
The margaritifer Sinus quadrangle is one of a series of 30 quadrangle maps of Mars used by the United States Geological Survey Astrogeology Research Program. The Margaritifer Sinus quadrangle is also referred to as MC-19 ....
have been proposed as areas to send NASA's next major Mars rover, the Mars Science Laboratory (MSL). Eberswalde Crater was shortlisted as one of the final four proposed landing sites for the Curiosity rover, part of the MSL mission. It was voted a close second after Gale Crater by a team of scientists.
MRO
Mars Reconnaissance Orbiter
Mars Reconnaissance Orbiter is a NASA multipurpose spacecraft designed to conduct reconnaissance and Exploration of Mars from orbit...
discovered iron/magnesium smectites here. This mineral requires water to form.
Eberswalde Delta
The crater contains a relief inversion, an exhumed deltaRiver delta
A delta is a landform that is formed at the mouth of a river where that river flows into an ocean, sea, estuary, lake, reservoir, flat arid area, or another river. Deltas are formed from the deposition of the sediment carried by the river as the flow leaves the mouth of the river...
formed by the flow of a liquid, most likely water. The series of valleys leading into the delta "drain
Drainage basin
A drainage basin is an extent or an area of land where surface water from rain and melting snow or ice converges to a single point, usually the exit of the basin, where the waters join another waterbody, such as a river, lake, reservoir, estuary, wetland, sea, or ocean...
" an area of approximately 4000 km². The surface area of the delta is 115 km², measuring 13 km by 11 km. The delta was discovered by Michael Malin and Kenneth Edgett of Malin Space Science Systems
Malin Space Science Systems
Malin Space Science Systems is a San Diego, California company that designs, develops, and operates instruments to fly on unmanned spacecraft. MSSS is headed by chief scientist and CEO Michael C. Malin....
through imagery taken by the Mars Global Surveyor
Mars Global Surveyor
The Mars Global Surveyor was a US spacecraft developed by NASA's Jet Propulsion Laboratory and launched November 1996. It began the United States's return to Mars after a 10-year absence. It completed its primary mission in January 2001 and was in its third extended mission phase when, on 2...
in 2003.
The delta also provides unambiguous evidence that some Martian sedimentary rocks have been deposited in a liquid. The meandering of the channels provides evidence to support this. Additional sediments were deposited on top of the delta, burying it. The deposits in the channels formed sedimentary rock. As the surrounding softer sediments were eroded away, the delta was exhumed, but inverted.
Based on an estimate by Moore et al. in 2003 of flow volume to the crater at 700 m3/s, it is estimated that it would take twenty years to completely fill the crater, ignoring evaporation
Evaporation
Evaporation is a type of vaporization of a liquid that occurs only on the surface of a liquid. The other type of vaporization is boiling, which, instead, occurs on the entire mass of the liquid....
and infiltration
Infiltration (hydrology)
Infiltration is the process by which water on the ground surface enters the soil. Infiltration rate in soil science is a measure of the rate at which soil is able to absorb rainfall or irrigation. It is measured in inches per hour or millimeters per hour. The rate decreases as the soil becomes...
. However, this is unlikely because it is hypothesized that the delta was not formed in a permanent lake but rather a series of short lacustrine
Lake
A lake is a body of relatively still fresh or salt water of considerable size, localized in a basin, that is surrounded by land. Lakes are inland and not part of the ocean and therefore are distinct from lagoons, and are larger and deeper than ponds. Lakes can be contrasted with rivers or streams,...
episodes on the order of years. This suggests that the Martian climate at the Noachian epoch time of formation was characterized by a series of short, wet spells rather than a sustained wet climate.
See also
- Mars Science LaboratoryMars Science LaboratoryThe Mars Science Laboratory is a National Aeronautics and Space Administration mission with the aim to land and operate a rover named Curiosity on the surface of Mars. The MSL was launched November 26, 2011, at 10:02 EST and is scheduled to land on Mars at Gale Crater between August 6 and 20, 2012...
- Geography of Mars
- River deltaRiver deltaA delta is a landform that is formed at the mouth of a river where that river flows into an ocean, sea, estuary, lake, reservoir, flat arid area, or another river. Deltas are formed from the deposition of the sediment carried by the river as the flow leaves the mouth of the river...
- the terrestrial equivalent
External links
- HiRISE image of Eberswalde Delta (warning: large images)
- MSSS page about the discovery