snow?

• by amogorkon

  is that white stuff snow or ice?

  Posted April 12, 2013 6:35 PM

• by Kitharode moderator

  Hi There. I'm going to suggest that this is ice. When the venting is less active it probably looks similar to this;

  http://planetfour.org/subjects/standard/50e746015e2ed21240005b39.jpg What do you think?

  Posted April 12, 2013 6:51 PM

• by JellyMonster

  It might be... CO2 snow that is!

  Posted April 12, 2013 6:51 PM

• by Kitharode moderator

  I've learnt that there's more snow on one side of the south pole than the other side, where there is more frost and ice. Something to do with a 'permanant' weather feature around those parts. So yes, it could be snow. I think ice. 😉

  Posted April 12, 2013 6:56 PM

• by wassock moderator

  There a region denoted "Cryptic" which is markedly colder than the rest of the polar region. It's vaguley between 150 and 310 degrees of longitude. Doesn't seem to be a consensus on why, best bet may be that it is a thick layer of co2 covered by a thick layer of dust which stops it melting in sumer.

  Posted April 12, 2013 8:59 PM

• by mschwamb scientist, translator in response to amogorkon's comment.

  There is a layer of ice but it's pretty translucent or you wouldn't have the fans, so I think between the fans you're seeing the dirt at the base of the ice sheet. Except it's just lightly colored.

  ~Meg

  Posted April 13, 2013 12:40 AM

• by mschwamb scientist, translator in response to wassock's comment.

  A lot of fan and spot activity has been associated with the cryptic terrain.

  The cryptic terrain in Piqueux et al. 2003 was described as:

  "These regions of the seasonal CO2 ice caps exhibit low albedo,
  characteristic of the underlying regolith material, despite retention
  of substantial CO2 ice covering, as evidenced by the observed
  brightness temperatures. It has been hypothesized that the simplest
  explanation for this ‘‘cryptic’’ terrain is the development in these
  regions of large-grained ‘‘slab’’ ice, which is transparent to visible
  light [Kieffer et al., 2000]. Alternatively, these dark and cold
  regions may be due to contamination of the seasonal ice with dust."

  Hansen et al. 2010 - describe the cryptic region as:

  Cryptic terrain (a large region near the south pole of Mars termed
  ‘‘cryptic” because even though its albedo darkens in the spring it
  retains the 145 K temperature of CO2 ice until late in the season)
  which contains a host of phenomena that are inferred to arise from
  local gas jet activity (Kieffer, 2000; Christensen et al., 2005;
  Kieffer et al., 2006). Inca City is outside the cryptic region however
  it also shows evidence of gas jet activity in the form of fan-shaped
  deposits and morphology of the eroded surface.

  Cheers,

  ~Meg

  Posted April 13, 2013 12:55 AM