[X] My Assistant

[kwan3217]

I got bored, and so I wasted an evening copying numbers out of the http://phoenix.lpl.arizona.edu/videos.php#edl_hud EDL HUD videos. Yellow numbers are entered from the movie, all other numbers are calculated. Sometimes I used the metric form, sometimes english, they seem to be consistent with each other where I checked. Data points are at least one every five seconds, as well as the exact time of every event or phase change, and at one second intervals in other places. Timing is based on the movie frame number, and a frame rate of exactly 30fps (29.97fps is two frames different every 60 seconds, not measurably different.)

The most important thing I learned: The movie is not internally consistent , especially from lander separation to touchdown. Specifically, the altitude does not change at the rate that the vertical speed says it should. It is also not consistent with any timeline I have seen in print. Still, I believe it at least to parachute deployment.

Make of this what you will.

Attached File(s)

 Phoenix_Nominal_EDL.xls ( 87.5K ) Number of downloads: 292

 

[dmuller]

Kwan3217, I did some of that work as well for the real-time simulation. I noticed the problems after landing separation as well, in my case it manifested in the altitude being higher than the distance remaining to fly (which I based on speed). But more importantly, it seems to follow an older version of the timeline, with lander separation something like 25 secs before landing BUT according to the latest landing events posted on http://www.nasa.gov/mission_pages/phoenix/...dingevents.html this event now takes place around 45 secs before landing.

Nevertheless, it remains the best and most scientific landing animation I've ever seen.

Daniel

[kwan3217]

I agree, it is a really nice animation. We only criticize what we care about.