InSight Cruise Phase, Events during Mars transit prior to EDL Options

[nprev]

Hey again, everyone. This thread will be for discussion of anything that happens between now & landing day, currently 26 Nov US Pacific time (UTC-8 hrs during that part of the year).

[mcaplinger]

Attached is a text file with 1-minute sampling from the SPK file https://naif.jpl.nasa.gov/pub/naif/INSIGHT/...e09o_edl_v1.bsp -- items are J2000 time, distance from Mars center in km, and XYZ position and velocity in km from Mars center and km/sec, both in Mars body-fixed (iau_mars) reference frame.

Most of the SPK files on NAIF don't appear to have the landing portion modeled in them, they fly past Mars (atmosphere unmodeled, maybe.)

 edl.txt ( 34.22K ) Number of downloads: 809

[Guest_mcmcmc_*]

Most of the SPK files on NAIF don't appear to have the landing portion modeled in them, they fly past Mars (atmosphere unmodeled, maybe.)

Too many variables and randoms factor to predict anything during EDL: each major event (parachute, heatshield, backshield) spans in a range of 20 seconds, i.e. "who knows when it will happen"?
No luck also with Horizons data.

Anyway what I am actually trying to build is a Phoenix simulator... which can be used, with a little of imagination and manually starting/restarting each event when NASA announces it has been confirmed, to "visualize" what is (approximately) happening in Mars sky during those 6 minutes of terror on 26/11. :-)
And it will also be useful to analyze actual data after landing.

[mcaplinger]

Too many variables and randoms factor to predict anything during EDL: each major event (parachute, heatshield, backshield) spans in a range of 20 seconds, i.e. "who knows when it will happen"?

Well, the way this works for the team (and I was pretty involved in this for MPL, PHX, and MSL) is that hundreds of Monte Carlo runs are done and the probability distribution of when major events could happen is calculated. Some parts of the descent are pretty locked down (for example, powered descent duration can't vary by much because you run out of fuel if it goes too long and you crash if it goes too short) whereas some parts are highly variable (time spent on parachute, for example).

BTW, I can't download the attachment from my last message and maybe you can't either (some forum issue?), but I guess you're not interested anyway.

[Guest_mcmcmc_*]

(for example, powered descent duration can't vary by much because you run out of fuel if it goes too long and you crash if it goes too short

this remembers me of something...

how do Phoenix and Insight prevent Schiaparelli final event from happening?
And by the way, recorded data on Phoenix show and incredibly wrong modelization of Pitch, Roll and Yaw for Phoenix:
https://ntrs.nasa.gov/archive/nasa/casi.ntr...20080034645.pdf

(fig. 6, 7, 8).

By the way, is anything similar to Phoenix raw data available for unfortunate Schiaparelli mission? Or was it supposed to upload them once landed?

[mcaplinger]

And by the way, recorded data on Phoenix show and incredibly wrong modelization of Pitch, Roll and Yaw for Phoenix:
By the way, is anything similar to Phoenix raw data available for unfortunate Schiaparelli mission? Or was it supposed to upload them once landed?

Has it occurred to you that maybe the problem is your interpretation of the data, not that they are "incredibly wrong"?

There was some realtime downlink of Schiaparelli data, I think it's described in the failure report. I'd be very surprised if it was online in raw form.

Here's the Insight dump with 1-second intervals.

 edl.zip ( 2.37MB ) Number of downloads: 344

[Guest_mcmcmc_*]

Has it occurred to you that maybe the problem is your interpretation of the data, not that they are "incredibly wrong"?

Suggestions?
I just see two heavily different curves named "predicted" amd "reconstructed".

Here's the Insight dump with 1-second intervals.

 edl.zip ( 2.37MB ) Number of downloads: 344

No way to download this file, still gives an error, anyway never mind, I tried setting up the simulator with data I have:
http://win98.altervista.org/space/explorat...-simulator.html

It has yet to be cleaned up and I'll try to also add some fancy graphical instrument like I did here, if I have time, but time is short, only one week remains.

[propguy]

Latest status. We did TCM5 yesterday (could not mention until official announcement came out Official InSight Twitter Page). So far looks like very good maneuver (well than 1 sigma error) and just waiting for Nav results to see if we are setup for entry as expected. Hoping to skip TCM6 this weekend, but ready if we have to do it. Things looking good for EDL.

On a side note, I have been trying to come up with a good EDL song to play that day on the way into work. For launches there are lots of ones that work, but none that seem to cover landing. Best I could think of was Helter Skelter "Coming down fast from miles above you". Good line but the rest of the song does not fit my hopes for that day. Any good ideas?

[mcaplinger]

Any good ideas?

"Eight Miles High" by the Byrds?