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mcaplinger
Posted on: Dec 24 2018, 08:00 PM


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The first batch of images has been pushed to https://www.missionjuno.swri.edu/
  Forum: Juno · Post Preview: #242733 · Replies: 89 · Views: 91111

mcaplinger
Posted on: Dec 16 2018, 08:50 PM


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QUOTE (MarkL @ Dec 16 2018, 06:36 AM) *
598143893 is seconds after Jan 1/2000 - December 14, 2018 at 11:04 p.m.

Based on the most recent clock drift file, that time maps to 2018 DEC 15 11:05:20 assuming it's really a raw SCLK value. 0 SCLK is nominally 2000-001T12:00.

CODE
from spice import *
furnsh("naif0012.tls")
furnsh("NSY_SCLKSCET.00010.tsc")
t0=scs2e(-189,"598143893")
print "t0", t0, et2utc(t0, "c", 0)
  Forum: InSight · Post Preview: #242616 · Replies: 1270 · Views: 1002250

mcaplinger
Posted on: Dec 11 2018, 01:04 AM


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QUOTE (Phil Stooke @ Dec 10 2018, 04:54 PM) *
And no thrusters, or am I missing them?

I think the cruise thrusters are there on the left side.
  Forum: InSight · Post Preview: #242511 · Replies: 1270 · Views: 1002250

mcaplinger
Posted on: Dec 6 2018, 08:04 PM


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QUOTE (Liss @ Dec 6 2018, 04:24 AM) *
is it correct that the nine-digit number in the image filenames is the time in seconds from 2000-Jan-01 12:00 UTC?

Nominally, but the clock isn't perfect and drifts a small amount. See https://naif.jpl.nasa.gov/pub/naif/INSIGHT/...KSCET.00009.tsc

And I don't know what the relationship between the time and the actual exposure time is for InSight. It takes tens of seconds to read the image out, though, so it might be off by that much at least.
  Forum: InSight · Post Preview: #242432 · Replies: 1270 · Views: 1002250

mcaplinger
Posted on: Dec 6 2018, 02:39 AM


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QUOTE (nprev @ Dec 5 2018, 05:23 PM) *
Yeah, that bitrate ain't gonna cut it for sure. Thanks! smile.gif

MMO would have gotten something like a peak of 80 kbits/sec at closest Mars range using Ka-band. https://www.hou.usra.edu/meetings/smallsat2...df/20_Malin.pdf
  Forum: Mars · Post Preview: #242415 · Replies: 10 · Views: 19971

mcaplinger
Posted on: Dec 6 2018, 01:32 AM


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QUOTE (Explorer1 @ Dec 5 2018, 08:17 AM) *
a NASA/ESA partnership seems like the best way to split the costs.

FWIW, I'm unconvinced that international cooperation ever saves money if a full cost accounting is done.
  Forum: Past and Future · Post Preview: #242412 · Replies: 579 · Views: 574619

mcaplinger
Posted on: Dec 5 2018, 10:45 PM


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12U cubesat: https://en.wikipedia.org/wiki/Mars_Micro_Orbiter

wikipedia is a little out of date, mission wasn't funded for launch in 2020.
  Forum: Mars · Post Preview: #242408 · Replies: 10 · Views: 19971

mcaplinger
Posted on: Dec 2 2018, 01:22 AM


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QUOTE (marsophile @ Dec 1 2018, 05:09 PM) *
This image from the IDC camera is more obscured than from the other cameras.

There are only two cameras, ICC and IDC. This is an image with the sun near the FOV. I assumed they moved the arm and this is the sky.

I'm not sure if the IDC had a cover (website says there is one, but I'm not sure if that's true) or if it's been removed.

https://www.hou.usra.edu/meetings/lpsc2018/pdf/2764.pdf
  Forum: InSight · Post Preview: #242305 · Replies: 1270 · Views: 1002250

mcaplinger
Posted on: Dec 1 2018, 10:20 PM


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QUOTE (MahFL @ Dec 1 2018, 01:36 PM) *
As it is, the Insight lander is heavier than Phoenix, using the same landing jets...

10 kg more landed mass from what I can tell (360 kg for InSight). From what I know of the design I don't think there's a lot more mass margin. All 12 engines at full thrust produces about 3600 newtons which is about 2.6x more than needed to hover (if I did that right), but they don't run all 12 engines at full thrust and there's the rocket equation to think of.
  Forum: InSight · Post Preview: #242301 · Replies: 1270 · Views: 1002250

mcaplinger
Posted on: Dec 1 2018, 09:30 PM


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QUOTE (JRehling @ Dec 1 2018, 12:25 PM) *
I'm not sure that anyone has made any mistakes in the posts above, but there's a lot of potential confusion here.

If you say that something weighs X kilograms, you really mean that it has a mass of X kilograms. I've never heard anyone in aerospace try to use some other verb than weigh in this context. Using "mass" as a verb ala Heinlein has never caught on.

Units of force are a different matter and in my experience that's where the confusion comes in.
  Forum: InSight · Post Preview: #242299 · Replies: 1270 · Views: 1002250

mcaplinger
Posted on: Dec 1 2018, 08:15 PM


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The dust on the ICC lens makes me wonder how dusty the Phoenix MARDI would have been had we ever managed to get a post-landing image out of it. Unfortunately there was a sequence glitch in the one attempt that was made, and PHX died before we could try again.
  Forum: InSight · Post Preview: #242297 · Replies: 1270 · Views: 1002250

mcaplinger
Posted on: Dec 1 2018, 06:00 PM


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QUOTE (Steve G @ Dec 1 2018, 09:49 AM) *
the additional weight is not that restrictive.

Uh, what? How much do you think arms weigh?

The original MSL design did have two arms, one for sampling and one for contact science, but that got descoped pretty quickly.
  Forum: InSight · Post Preview: #242293 · Replies: 1270 · Views: 1002250

mcaplinger
Posted on: Dec 1 2018, 03:20 AM


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QUOTE (nprev @ Nov 30 2018, 06:37 PM) *
Is the ICC cover still on, then?

As noted, it's off. The cover didn't work very well, apparently.

Turns out that very wide-field fisheyes like this one can be more susceptible than narrower-field optics to dust contamination, somewhat paradoxically.
  Forum: InSight · Post Preview: #242269 · Replies: 1270 · Views: 1002250

mcaplinger
Posted on: Nov 30 2018, 08:21 PM


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QUOTE (elakdawalla @ Nov 30 2018, 12:07 PM) *
Whoa!

Keep in mind that the landing ellipse was several CTX swaths wide, so missing wouldn't be that surprising.
  Forum: InSight · Post Preview: #242254 · Replies: 1270 · Views: 1002250

mcaplinger
Posted on: Nov 30 2018, 08:04 PM


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QUOTE (nprev @ Nov 29 2018, 05:04 AM) *
The location 'race' is interesting...

[deleted]
  Forum: InSight · Post Preview: #242252 · Replies: 1270 · Views: 1002250

mcaplinger
Posted on: Nov 29 2018, 04:11 AM


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QUOTE
A Mars orbiter set to image the center of the landing zone on Thursday will miss the lander, because it missed the center slightly.

Missed with HiRISE. If only there was a wider-field "context camera"... rolleyes.gif
  Forum: InSight · Post Preview: #242202 · Replies: 1270 · Views: 1002250

mcaplinger
Posted on: Nov 29 2018, 03:17 AM


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QUOTE (atomoid @ Nov 28 2018, 04:15 PM) *
I guess the Insight team decided to not to even include a MARDI for that or perhaps other reasons as well, so no descent images to help define the landing context.

We offered a number of options, but they chose not to use any of them (of course they had a cost.)

In all honesty the landing context argument isn't extremely compelling, assuming we get HiRISE images post-landing.
  Forum: InSight · Post Preview: #242201 · Replies: 1270 · Views: 1002250

mcaplinger
Posted on: Nov 26 2018, 08:26 PM


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QUOTE (fredk @ Nov 26 2018, 12:19 PM) *
First image up already!

Huh. Crud on the dust cover is a lot clumpier looking than what we got on the MAHLI dust cover on MSL. Maybe more localized material from the different thruster configuration and camera placement.
  Forum: InSight · Post Preview: #242055 · Replies: 119 · Views: 126929

mcaplinger
Posted on: Nov 24 2018, 04:41 PM


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QUOTE (mcmcmc @ Nov 24 2018, 07:53 AM) *
How can we answer above questions without any method available to know lander tilt and wind speed and direction during landing?

The tilt at landing is well-known from looking at the gravity vector and the vehicle is actively controlling its attitude during powered descent. The tilt in the last 10 seconds of parachute descent, for example, is completely irrelevant to the tilt at landing.

Varying atmospheric conditions are the major reason that the landing ellipses are relatively large.
  Forum: InSight · Post Preview: #241946 · Replies: 129 · Views: 147599

mcaplinger
Posted on: Nov 24 2018, 04:25 PM


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The way EDL is validated is that many Monte Carlo runs are done with all of the parameters varied across their expected ranges and we see if the landing is successful.

Most of this is covered by ITAR so I wouldn't expect to see public information about the specifics.
  Forum: InSight · Post Preview: #241945 · Replies: 129 · Views: 147599

mcaplinger
Posted on: Nov 24 2018, 03:34 PM


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QUOTE (mcmcmc @ Nov 24 2018, 04:04 AM) *
The point is: if you are going to land on Mars (not "generic you", but you nprev or djellison), wouldn't you like to know in advance how your spaceship/spacecraft/aircraft/whatelse will be oriented during final descent?

You need to calm down a little.

Certainly for previous landings there have been a lot of simulations of what the attitude on chute was, and we used them to calculate exposure times, photometric angles, etc, but at best they were measures of what could have happened. Nobody expected them to look much like reality, and they didn't. For example, the MSL descent was much less oscillatory than some of the simulations.
  Forum: InSight · Post Preview: #241942 · Replies: 129 · Views: 147599

mcaplinger
Posted on: Nov 20 2018, 04:16 AM


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QUOTE (propguy @ Nov 19 2018, 04:38 PM) *
Any good ideas?

"Eight Miles High" by the Byrds?
  Forum: InSight · Post Preview: #241870 · Replies: 129 · Views: 147599

mcaplinger
Posted on: Nov 19 2018, 03:50 PM


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I'm having a hard time adding attachments over on the Insight thread. The upload seems to work but when I try to download, I just get an error message about not having permissions.
  Forum: Forum Maintenance · Post Preview: #241857 · Replies: 36 · Views: 239827

mcaplinger
Posted on: Nov 19 2018, 03:48 PM


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QUOTE (mcmcmc @ Nov 19 2018, 07:21 AM) *
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.

Attached File  edl.zip ( 2.37MB ) Number of downloads: 380
  Forum: InSight · Post Preview: #241856 · Replies: 129 · Views: 147599

mcaplinger
Posted on: Nov 18 2018, 10:55 PM


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QUOTE (mcmcmc @ Nov 18 2018, 01:52 PM) *
you said it does not cover EDL part, so I didn't even try downloading it.

I said most of the kernels on the NAIF site don't model the landing. The one I extracted the data from does at least at some level, otherwise I wouldn't have bothered with it.
  Forum: InSight · Post Preview: #241847 · Replies: 129 · Views: 147599

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