Featured Research

from universities, journals, and other organizations

Rare Martian lake delta spotted by Mars Express

Date:
September 3, 2011
Source:
European Space Agency (ESA)
Summary:
The European Space Agency's Mars Express has spotted a rare case of a crater once filled by a lake, revealed by the presence of a delta. The delta is an ancient fan-shaped deposit of dark sediments, laid down in water. It is a reminder of Mars' past, wetter climate.

Holden crater is 140 km across, filling the left side of the image, while to the right is the remaining part of Eberswalde crater, with a diameter of about 65 km. They are located in the southern highlands of Mars. North is to the right of the image. The image was acquired by Mars Express at approximately 25°S / 326°E during orbit 7208 on 15 August 2009. The images have a ground resolution of about 22 m per pixel.
Credit: ESA/DLR/FU Berlin (G. Neukum)

The European Space Agency's Mars Express has spotted a rare case of a crater once filled by a lake, revealed by the presence of a delta. The delta is an ancient fan-shaped deposit of dark sediments, laid down in water. It is a reminder of Mars' past, wetter climate.

The delta is in the Eberswalde crater, in the southern highlands of Mars. The 65 km-diameter crater is visible as a semi-circle on the right of the image and was formed more than 3.7 billion years ago when an asteroid hit the planet.

The rim of the crater is intact only on its right-hand side. The rest appears only faintly or is not visible at all. A later impact created the 140 km diameter Holden crater that dominates the centre and left side of the image. The expulsion of large amounts of material from that impact buried parts of Eberswalde.

However, within the visible part of Eberswalde, the delta and its feeder channels are well preserved , as seen near the top right of the crater. The delta covers an area of 115 square kilometres. Small, meandering feeder channels are visible towards the top of the crater, which would have filled it to form a lake.

After the deposition of the delta sediments in the crater's ancient lake, fresher sediments accumulated to cover up a major part of both the channels and the delta. These secondary sediments, presumably deposited by the wind, were later eroded in the delta area, exposing an inverted relief of the delta structure.

This delta structure, first identified with NASA's Mars Global Surveyor spacecraft, is characteristic of the presence of a lake in the crater at that time. Such features provide a clear indication that liquid water flowed across the surface of Mars in the planet's early history.

Both Eberswalde crater and Holden crater were on the shortlist of four possible destinations for the next NASA Mars rover, to be launched late this year. The main objective of the Mars Science Laboratory mission is the search for present or previously habitable environments on Mars. ESA's Mars Express mission has been helping in the search for the best landing site.

Eberswalde was proposed because its delta indicates the long-lasting presence of liquid water in the past and Holden Crater was a candidate because of its mineral diversity and many structures that again suggest past liquid water. Another candidate, Mawrth Vallis, exposes some of the oldest clay-rich layers on Mars. However, in July, Gale crater, the final entry on the shortlist, was selected as the mission's landing site, given its high mineral and structural diversity related to water.

Eberswalde, Holden and Mawrth Vallis will get to hold on to their secrets for a while longer.


Story Source:

The above story is based on materials provided by European Space Agency (ESA). Note: Materials may be edited for content and length.


Cite This Page:

European Space Agency (ESA). "Rare Martian lake delta spotted by Mars Express." ScienceDaily. ScienceDaily, 3 September 2011. <www.sciencedaily.com/releases/2011/09/110902104746.htm>.
European Space Agency (ESA). (2011, September 3). Rare Martian lake delta spotted by Mars Express. ScienceDaily. Retrieved September 17, 2014 from www.sciencedaily.com/releases/2011/09/110902104746.htm
European Space Agency (ESA). "Rare Martian lake delta spotted by Mars Express." ScienceDaily. www.sciencedaily.com/releases/2011/09/110902104746.htm (accessed September 17, 2014).

Share This



More Space & Time News

Wednesday, September 17, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

East Coast Treated To Rare Meteor Sighting

East Coast Treated To Rare Meteor Sighting

Newsy (Sep. 16, 2014) — Numerous residents along the East Coast reported seeing a bright meteor flash through the sky Sunday night. Video provided by Newsy
Powered by NewsLook.com
Space Race Pits Bezos Vs Musk

Space Race Pits Bezos Vs Musk

Reuters - Business Video Online (Sep. 16, 2014) — Amazon CEO Jeff Bezos' startup will team up with Boeing and Lockheed to develop rocket engines as Elon Musk races to have his rockets certified. Fred Katayama reports. Video provided by Reuters
Powered by NewsLook.com
NASA’s Curiosity Rover Finally Reaches Long-Term Goal

NASA’s Curiosity Rover Finally Reaches Long-Term Goal

Newsy (Sep. 15, 2014) — After more than two years, NASA’s Mars Curiosity Rover reached Mount Sharp, its long-term destination. Video provided by Newsy
Powered by NewsLook.com
SpaceX's Elon Musk Really Wants To Colonize Mars

SpaceX's Elon Musk Really Wants To Colonize Mars

Newsy (Sep. 14, 2014) — Elon Musk has been talking about his goal of colonizing Mars for years now, but how much of it does he actually have figured out, and is it possible? Video provided by Newsy
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
 
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:  

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

    Environment News

      Technology News



      Save/Print:
      Share:  

      Free Subscriptions


      Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

      Get Social & Mobile


      Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

      Have Feedback?


      Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
      Mobile iPhone Android Web
      Follow Facebook Twitter Google+
      Subscribe RSS Feeds Email Newsletters
      Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins