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Pack-ice

Figure 1. Views of plate-like terrain on Mars, and pack-ice on Earth. From the paper linked below.

a, Part of an HRSC image of Mars from orbit 32, with a resolution of 13.7 m per pixel, centred at 5.5° north latitude and 150.4° east longitude, showing plate-like deposits with signs of break-up, rotation and lateral movement to the west-southwest in the lower part of the image. Scale bar is 25 km. b, Synthetic Aperture Radar image of pack-ice in the Weddell Sea, Antarctica. Scale bar is 25 km. (ESA image, processed by H. Rott.) c, Enlarged view of raft 7 × 12 km showing 8° rotation anticlockwise, causing the clear lane downstream of island ‘I’ to be curved. Leads ‘L’ downstream of the crater and small island at lower right are almost straight, indicating unidirectional drift slightly north of westward. Note pressure ridges ‘P’ upstream of islands. Arrows show relative motion vectors of individual plates. Scale bar is 10 km.

In Murray et al. (2005) in the journal Nature with the significant title "Evidence from the Mars Express High Resolution Stereo Camera for a frozen sea close to Mars'equator" images from the above-named camera are presented from which is inferred the existence of a frozen body of water, with surface pack-ice, around 5$^0$ north latitude and 150$^0$ east longitude in the Cerberus Palus region.
The frozen lake should measure about 800 x 900 km in lateral extent !

cerberus region

Have there been observations by any radar instrument or neutron detector that can confirm or invalidate the existence of the putative frozen lake in the Cerberus Palus region ?

And is there further evidence from high resolution cameras for the existence of ice deposits within this region since the publication of the article in 2005 ?

Figure from "Evidence from the Mars Express High Resolution Stereo Camera for a frozen sea close to the Mars' equator" Flooded craters

Evidence of ice surface lowering and draping of plain-like features over partly submerged craters.

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  • $\begingroup$ What does the article say about that? It's paywalled so we can't read it. Currently it looks like you're just assuming there have been no SHARAD observations. $\endgroup$ – Hobbes Jun 13 '18 at 11:50
  • $\begingroup$ You don't explore with radar, the SHARAD instrument's already done it's job. Perhaps the question should be what the next step is, how it would be validated. $\endgroup$ – GdD Jun 13 '18 at 11:54
  • $\begingroup$ @Hobbes You can read it if you crash the paywall ! I've changed the last question somewhat. $\endgroup$ – Conelisinspace Jun 13 '18 at 12:20
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    $\begingroup$ What are results of neutron scatterimg from Cerberus Palus? Neutrons are indicator of hydrogen amount in soil, and hydrogen means water. $\endgroup$ – Heopps Jun 13 '18 at 13:26
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    $\begingroup$ @Conelisinspace yes, but I meant if the ice is deeper, neutrons don't show it. Radar have deeper penetration. $\endgroup$ – Heopps Jun 13 '18 at 15:44
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This paper reports SHARAD observations of this site, and also references previous publications based on an earlier radar instrument MARSIS. It's complicated and the data seems to be ambiguous, but the bottom line appears to be that it isn't a large lake of solid ice. It might be broken up volcanic rock with ice filling the spaces, or it might just be rock. There could also be thin layers of almost anything, because the radar doesn't see them

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  • $\begingroup$ Impressive paper, thank you ! Maybe the Exomars Trace Gas Orbiter, which has also a neutron detector will give us still more information. $\endgroup$ – Conelisinspace Jun 13 '18 at 13:27
  • $\begingroup$ Maybe the porous material could be carbon dioxide clathrate. $\endgroup$ – Conelisinspace Jun 13 '18 at 19:19
  • $\begingroup$ Added some pictures and another question $\endgroup$ – Conelisinspace Jun 14 '18 at 8:51

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