There's always laser altimeters for altitude and doppler Lidar for relative velocity.

Might be worth it for the 2020 surface platform to check into what's available, especially inhouse with ESA members and associates. OPTEL-D with AIM heritage comes to mind as a family of something that could possibly be further downsized to a sufficiently low footprint.

I'd think, they'll "simply" fix the glitch(es) or parameter settings, without fundamental changes of the design.

Edit: Altitude and veolcity of the EDM were determined by radar:

HiRISE images out : http://www.jpl.nasa.gov/news/news.php?feature=6663 Definitely heat shield separation, but a strange streak going east of the lander crash.

Radar is an extremely robust and mature technology and the larger beam footprint and longer wavelength can be an advantage. The landing applications for lidar I know of are for terrain hazard avoidance, not altitude/velocity determination per se, for example https://www-robotics.jpl.nasa.gov/publicati...aejJGCD2002.pdf

AFAIK, every successful Mars lander (and Moon lander, for that matter) has used radar.

That is definitely a strange streak. Maybe that's the mini-version of a crater ray: The splash of some small-scale debris from the impact site. Another thought: Perhaps that's a location where a small, random feature in the sub-dust topography had less dust adhering to it. The smoothness of the curve, however, doesn't look like typical rock morphology on that scale. Maybe the impact stirred up a mini dust devil?

It could be that a pressurised tank was let free in the impact and the curved streak represents the path the tank took while it was depressurising. Just throwing ideas out there, I doubt we'll ever know for sure.

http://photojournal.jpl.nasa.gov/figures/PIA21130_fig2.jpg

There is no sign of the curved "tail" in the CTX image taken last week, so it may have developed since then from debris or disturbed soil blown by the wind.

This is a comparison of the CTX and HIRISE images as best I can match them by the eye. I guess the tail could be lost by the low resolution. There might also be some dispersion of the debris in the time between the images.

There's also no signs in the CTX of the rather prominent craters just west of, and south of, the impact site. Either those craters are also a few days old or the CTX image doesn't really have the resolution and/or signal-to-noise ratio to see such finer details.

I think this is the right solution. This may be a trace of a rotating and ruptured tank. This explains the arc.

Little snippets of information still coming out, one saying the lander swung too much while on the parachute confusing the the altimeter causing the computer to look for radar which wasnt on (maybe). Computer triggers remaining decent sequences, even science instruments turned on, thinking it had landed !

Could the lack of curved tail be explained by different lighting angles between the two images?

It is a resolution issue, but I don't agree that it is not visible in CTX. There is a dark pixel in CTX at exactly the right place.


Phil

Could someone cognisant speculate on how hydrazine might behave if exposed to martian surface conditions?
For instance, would it burn, explode, quickly evaporate, or linger?

MSL's hazcam showed the skycrane explosion as a big plume, but there wasn't enough detail to tell if it was smoke from some chemical reaction/combustion or just a dust cloud from the impact itself. They obviously didn't want to risk exposure to toxic hardware to take a closer look with the rover though....