[meteorite-list] Very cool Impact Crater on Mars

[Pete Pete]

Amazing hi-res pictures at the source site:

http://www.esa.int/SPECIALS/Mars_Express/SEMZLM8A9HE_0.html

http://www.esa.int/SPECIALS/Mars_Express/SEMZLM8A9HE_0.html

News

‘Butterfly’ impact crater in Hesperia Planum



Colour view of 'butterfly'-shaped crater at Hesperia Planum

4 January 2006
These images, taken by the High Resolution Stereo Camera (HRSC) on board 
ESA’s Mars Express spacecraft, show a large elliptical impact crater in the 
Hesperia Planum region of Mars.


Map showing 'butterfly' crater in context
The HRSC obtained these images during orbit 368 with a ground resolution of 
approximately 16.7 metres per pixel. The scenes show the region of Hesperia 
Planum, at approximately 35.3° South and 118.7° East.
A large elliptical impact crater is visible within the scene, measuring 
approximately 24.4 km long, 11.2 km wide and reaching a maximum depth of 
approximately 650 metres below the surrounding plains.


Black and white nadir view of Hesperia Planum
Ejecta from this impact can be seen extending away from the crater, 
including two prominent lobes of material north-west and south-east of the 
crater.

The large circular feature, partly cut off by the border of the image, has a 
diameter of roughly 45 km.

This appears to be an impact crater that was subsequently resurfaced by lava 
flows, preserving the outline of the underlying crater. The curving features 
visible in the north of the image, known as ‘wrinkle ridges’, are caused by 
compressional tectonics.


Close-up perspective view of 'butterfly' crater - looking north
While the majority of impact craters are relatively circular, the elliptical 
shape of this impact crater suggests a very low impact angle (less than 10 
degrees).

The long axis of the impact crater is viewed as the impacting direction of 
the projectile. Similar elliptical craters are observed elsewhere on Mars, 
as well as on our Moon.

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.

3D anaglyph view of Hesperia Planum
The 3D anaglyph image was calculated from the nadir and one stereo channel. 
Image resolution has been decreased for use on the internet.

For more information on Mars Express HRSC images, you might like to read our 
updated 'Frequently Asked Questions'.