[meteorite-list] Mars Express Images: Breathtaking Views of Deuteronilus Mensae on Mars

From: Ron Baalke <baalke_at_meteoritecentral.com>
Date: Mon, 21 May 2007 11:17:15 -0700 (PDT)
Message-ID: <200705211817.LAA00729_at_zagami.jpl.nasa.gov>

http://www.esa.int/esaSC/SEMBS5V681F_index_0.html

Breathtaking views of Deuteronilus Mensae on Mars
Deuteronilus Mensae region on Mars
Mars Express
European Space Agency
21 May 2007

The High Resolution Stereo Camera (HRSC) on board ESA's Mars Express has
captured breathtaking images of the Deuteronilus Mensae region on Mars.
 
The images were taken on 14 March 2005 during orbit number 1483 of the
Mars Express spacecraft with a ground resolution of approximately 29
metres per pixel.

They show the Deuteronilus Mensae region, located on the northern edge
of Arabia Terra and bordering the southern highlands and the northern
lowlands. Situated at approximately 39?? North and 23?? East, Deuteronilus
Mensae are primarily characterised by glacial features. The scene is
illuminated by the Sun from the south-west (from bottom left in the image).

[Image]
Deuteronilus Mensae seen in context

The scene is dominated by a depression measuring approximately 2 000
metres in depth and 110 kilometres in diameter, north to south.

Visible in the centre of the first image, the interior of the depression
is characterised by dark material, differing from the light-toned
surrounding plains.

 
[Image]
Perspective view of Deuteronilus Mensae

Deeply incised valleys of a depth ranging from 800 to 1 200 metres are
clearly identifiable in the northern part of the scene. Deeply incised
valleys with a depth ranging from 800 to 1 200 metres are clearly
identifiable in the northern part of the scene.

It is believed that these valleys may have originated due to intense
flooding by melted water ice. The water then froze rather quickly,
flowing down the slopes of the depression like a glacier. Aeolian
sediments (eroded by the action of wind) traced the flow pattern on the
surface.

 
[Image]
Perspective view of Deuteronilus Mensae

The northern part exhibits a finger - shaped elevation which was
circumvented by the masses of water and ice.

To the west, the flow of water mixed with ice broke through another
elevation and formed a drop - shaped feature while flowing into the
depression.

 
[Image]
Black and white nadir view of Deuteronilus Mensae

Mars experienced numerous events of this kind in the past, when rising
magma or impacts caused frozen groundwater to melt resulting in major
flooding events.

One of the most striking features on Mars is the dichotomy between the
southern highlands and the northern plains, lower by up to 3 kilometres.
The boundary between these two regions is marked by a transition
characterised by an intact highland zone and areas with remnant mesas
and isolated eroded knobs.

The scene of Deuteronilus Mensae depicts different stages of highland
degradation. Numerous flow patterns in wide valleys and along ridges and
scarps indicate movement of debris mixed with ice towards the
surrounding areas.

Since the discovery of these structures, scientists assume that the
mixture of debris and ice resembles rock glaciers commonly found in
cold-climate areas on the Earth.

As on Earth, these landscapes are climate indicators. Whether ice could
be still present in the porous spaces in Martian features and how active
these landforms may be today is still a subject of discussion.

 
[Image]
3D Anaglyph view of Deuteronilus Mensae
 
The colour scenes have been derived from the three HRSC colour channels
and the nadir channel. The perspective views have been calculated from
the digital terrain model derived from the stereo channels.

The anaglyph image was calculated from the nadir and one stereo channel.
The black and white high - resolution images were derived from the nadir
channel which provides the highest detail of all channels. Image
resolution has been decreased for easier downloading.
Received on Mon 21 May 2007 02:17:15 PM PDT