20 June 2008
It's official – Phoenix has found ice!
Posted by briony
Some great news from Phoenix this morning: Phoenix has seen chunks of ice vaporize! (Press release via SpaceRef)
The chunks of white material were sitting at the bottom of a trench the lander dug 4 days ago, and after looking at the trench again this morning, the chunks appear to vanished! Here’s an animation showing the changes – look for the vanishing chunks in the shadow on the left side of the trench:
Because the chunks vanished, this lays to rest the theories that they may have been made of salts, which would not have vaporized like this. If we extrapolate this finding to the rest of the white material in the trenches, then that would mean that the hard layer that’s been found in several trenches so far is a continuous (at least locally) ice sheet. Awesome!
There is a certain type of salt that can evaporate similar in
appearance to what we are seeing here.
Doesn’t Phoenix have sensors somewhere that can determine
exactly what the white stuff is?
Is it true that TEGA was the least well planned instrument
of the bunch? That is odd considering how important the
device is to this mission.
I’m not aware of a salt that can completely vanish via dehydration – generally, salts tend to leave something behind after losing water or other volatiles.
Phoenix does have other instruments that should be able to identify ice. Aside from TEGA, Phoenix has an instrument on the arm that senses properties like conductivity, as well as the Surface Stereo Imager (the main camera) that has 12 different wavelength filters that should be able to pick out ice absorption bands.
I’m not sure why data from these instruments hasn’t been released yet – my guess is that the team is so busy getting the data and calibrating the instruments that they don’t feel the data is reliable enough yet. And I really can’t comment on how well planned TEGA was.
In any case, the vanishing chunks are pretty solid evidence for ice.
Some people are strange! They do readily believe there is rock but have trouble with water!
Has the white stuff a cell like structure? It may be Sepiolite and ice.
Mars terrain shown sofar appears to be a dust covered frozen over drained lake!
Is water on Mars lost from the thin atmosphere into space to be gathered by meteorites that then continue to carry it around in a vacuum?
I must admit that I am often baffled by space science!
[…] here’s a true color version of the images that showed the disappearing chunks of ice (press […]