IPB
X   Site Message
(Message will auto close in 2 seconds)

Welcome Guest ( Log In | Register )

462 Pages V  « < 6 7 8 9 10 > » 

djellison
Posted on: Feb 28 2021, 12:59 AM


Founder
****

Group: Chairman
Posts: 14457
Joined: 8-February 04
Member No.: 1


QUOTE (HSchirmer @ Feb 27 2021, 03:36 PM) *
Eh, it's a large flat shiny white rock,


Looks the same as all the other rocks around to be honest - it just happens to be in the direction of the sun at 2-4pm in the afternoon and so is getting some glinting going on when it's photographed.

Take the images about 5 hours earlier and I'd bet we be remarking just how 'shiny' this pile of rocks is
https://mars.nasa.gov/mars2020-raw-images/p...6_110085J01.png
  Forum: Perseverance- Mars 2020 Rover · Post Preview: #250371 · Replies: 477 · Views: 263318

djellison
Posted on: Feb 28 2021, 12:30 AM


Founder
****

Group: Chairman
Posts: 14457
Joined: 8-February 04
Member No.: 1


This is the best I could do with the Sol 3 Mastcam Z images of the foreground.

https://sketchfab.com/3d-models/m2020-landi...7c685f31cf97c30

Attached Image
  Forum: Perseverance- Mars 2020 Rover · Post Preview: #250370 · Replies: 477 · Views: 263318

djellison
Posted on: Feb 28 2021, 12:28 AM


Founder
****

Group: Chairman
Posts: 14457
Joined: 8-February 04
Member No.: 1


The entire sequence ( ncam00598 ) started at 18:34:56 LMST and finished at 19:25:36 LMST

Sunset based on local topography was 18:23 LMST
  Forum: MSL · Post Preview: #250369 · Replies: 990 · Views: 555597

djellison
Posted on: Feb 26 2021, 05:45 PM


Founder
****

Group: Chairman
Posts: 14457
Joined: 8-February 04
Member No.: 1


Ahh ok - they miss spoke at yesterdays thing then. This matches MSL Mastcam Left then smile.gif
  Forum: Perseverance- Mars 2020 Rover · Post Preview: #250312 · Replies: 178 · Views: 141331

djellison
Posted on: Feb 26 2021, 05:30 PM


Founder
****

Group: Chairman
Posts: 14457
Joined: 8-February 04
Member No.: 1


Jim has put out a Mastcam-Z filename decode guide

https://mastcamz.asu.edu/decoding-the-raw-p...mage-filenames/

It includes digits in there that describe the focal length in mm as three digits.

All the stereo pan images report 34mm for that - which matches the widest angle of Mastcam-Z MSL Mastcam Left.
  Forum: Perseverance- Mars 2020 Rover · Post Preview: #250310 · Replies: 178 · Views: 141331

djellison
Posted on: Feb 26 2021, 04:37 AM


Founder
****

Group: Chairman
Posts: 14457
Joined: 8-February 04
Member No.: 1


QUOTE (MahFL @ Feb 25 2021, 05:10 PM) *
Is the software switch over currently happening to the surface ops s/w ?


Yes. Things should get back to normal at the weekend.
  Forum: Perseverance- Mars 2020 Rover · Post Preview: #250296 · Replies: 477 · Views: 263318

djellison
Posted on: Feb 25 2021, 04:17 AM


Founder
****

Group: Chairman
Posts: 14457
Joined: 8-February 04
Member No.: 1


QUOTE (spacepoint @ Feb 24 2021, 01:18 PM) *
IMHO, orientation of rover is correct to think that is actually back shell, flipped. blink.gif



No - it isn't. The shiny rock is left of the distant mesa. The parachute and backshell are to the right of the distant mesa.
  Forum: Perseverance- Mars 2020 Rover · Post Preview: #250261 · Replies: 477 · Views: 263318

djellison
Posted on: Feb 25 2021, 02:04 AM


Founder
****

Group: Chairman
Posts: 14457
Joined: 8-February 04
Member No.: 1


It's not great - but this is my agisoft metashape results with the Navcam images so far
https://sketchfab.com/3d-models/m2020-landi...7215aa7db2fb0c8
  Forum: Perseverance- Mars 2020 Rover · Post Preview: #250249 · Replies: 178 · Views: 141331

djellison
Posted on: Feb 24 2021, 08:34 PM


Founder
****

Group: Chairman
Posts: 14457
Joined: 8-February 04
Member No.: 1


QUOTE (MERovingian @ Feb 24 2021, 11:59 AM) *
So, it's the backshell then?


No - the backshell isn't in that direction.

Here is the basemap ( https://mars.nasa.gov/mars2020/mission/where-is-the-rover/ ) with hardware image ( https://www.uahirise.org/releases/persevera...ware-labels.jpg ) reprojected on to it. There is no hardware south of that distant mesa.
  Forum: Perseverance- Mars 2020 Rover · Post Preview: #250206 · Replies: 477 · Views: 263318

djellison
Posted on: Feb 24 2021, 03:38 PM


Founder
****

Group: Chairman
Posts: 14457
Joined: 8-February 04
Member No.: 1


Turned on just before chute deploy - but behind the cover that comes off at deployment, hence some black frames at the start of the sequence
  Forum: Perseverance- Mars 2020 Rover · Post Preview: #250193 · Replies: 122 · Views: 103950

djellison
Posted on: Feb 23 2021, 08:39 PM


Founder
****

Group: Chairman
Posts: 14457
Joined: 8-February 04
Member No.: 1


For the less technically minded among us...Ryan Kinnet has put up a page that grabs a listing with links to the PNG files that you can then use any browser-plugin-batch-downloader with

https://twitter.com/rover_18/status/1364309922167488512

I tried Firefox with 'DownloadThemAll' and it worked perfectly.

Meanwhile THIS GUY has python code to also grab the data
https://twitter.com/kevinmgill/status/1364311336000258048




  Forum: Perseverance- Mars 2020 Rover · Post Preview: #250146 · Replies: 178 · Views: 141331

djellison
Posted on: Feb 23 2021, 06:16 PM


Founder
****

Group: Chairman
Posts: 14457
Joined: 8-February 04
Member No.: 1


I'm not sure what product you're trying to make that isn't put into the PDS with a large code base and expansive documentation in a few months time, just like HiRISE etc.
  Forum: Perseverance- Mars 2020 Rover · Post Preview: #250139 · Replies: 477 · Views: 263318

djellison
Posted on: Feb 23 2021, 05:04 PM


Founder
****

Group: Chairman
Posts: 14457
Joined: 8-February 04
Member No.: 1


Easy test - go find the location in this map. If it's in this map - it's pre-EDL - it's just natural.

You don't mean this by any chance? This is pre-landing.
  Forum: Perseverance- Mars 2020 Rover · Post Preview: #250138 · Replies: 424 · Views: 308692

djellison
Posted on: Feb 23 2021, 03:35 PM


Founder
****

Group: Chairman
Posts: 14457
Joined: 8-February 04
Member No.: 1


QUOTE (erentar @ Feb 23 2021, 04:59 AM) *
like we have with MSL, but unfortunately that has to go through JPL MIPL which is apparently very secretive. JPL really is conservative when it comes to releasing their code.


There are reasons to be critical about how things have gone in terms of getting data out to the public over the past few days. But this is absolutely untrue.

Those mosaics from Curiosity are auto-generated after images are received after every drive, and every time there are updated images to add to them. They get sent out to the MSL internal server, a thumbnail gets emailed out to the team, and it gets uploaded to the MSL public website all using the same end-of-pass script. https://mars.nasa.gov/msl/multimedia/mosaics/ . This is not ‘very secretive’. It’s about as proactively open as it’s possible to be. It happens entirely hands off - no human in the loop - automatically. If I have been on shift sequencing images ...that public website is the place I go to see the end result first thing in the morning. I would expect that M2020 will probably get to the same point in the near future.

MIPL isn’t secretive. They have posters and presentations about their work at almost every planetary science conference I’ve seen. See https://trs.jpl.nasa.gov/handle/2014/42355 for example. As for ‘conservative when it comes to releasing their code’ - most of the MIPL code base is open source

https://www-mipl.jpl.nasa.gov/vicar_open.html
  Forum: Perseverance- Mars 2020 Rover · Post Preview: #250133 · Replies: 477 · Views: 263318

djellison
Posted on: Feb 22 2021, 12:50 AM


Founder
****

Group: Chairman
Posts: 14457
Joined: 8-February 04
Member No.: 1


I genuinely have no insider info for M2020 ECAM stuff - I'm guessing like everyone else - but it would appear....

Mars_Perseverance_RLB_0002_0667129492_604ECM_N0010052AUT_04096_00_2I3J01
Mars_Perseverance_RLG_0002_0667129481_373ECM_N0010052AUT_04096_00_2I3J01
Mars_Perseverance_RLR_0002_0667129466_057ECM_N0010052AUT_04096_00_2I3J01

Stack to an RGB image...... RLB being the Blue, RLG being the Green etc etc

Images like Mars_Perseverance_FRE_0000_0666958359_772ECM_N0010052AUT_04096_00_0LLJ01 - the E is raw and needs to be debayered ( I used Fitswork )
  Forum: Perseverance- Mars 2020 Rover · Post Preview: #250008 · Replies: 477 · Views: 263318

djellison
Posted on: Feb 22 2021, 12:48 AM


Founder
****

Group: Chairman
Posts: 14457
Joined: 8-February 04
Member No.: 1


QUOTE (Tom Ames @ Feb 21 2021, 04:37 PM) *
Re. the front Hazcams: is "A" the outboard of each L/R pair and "B" inboard?


A is the pair connected to the A flight computer, and B is the pair connected to the B flight computer

Image from https://link.springer.com/article/10.1007/s11214-020-00765-9
  Forum: Perseverance- Mars 2020 Rover · Post Preview: #250007 · Replies: 477 · Views: 263318

djellison
Posted on: Feb 21 2021, 08:46 PM


Founder
****

Group: Chairman
Posts: 14457
Joined: 8-February 04
Member No.: 1


QUOTE (John Whitehead @ Feb 20 2021, 09:24 PM) *
the sky crane engines are run at full throttle until the fuel depletes



Sorry to belabor this point - but they are not. I asked the EDL Phase lead. I refer you again to this paper : https://ieeexplore.ieee.org/stamp/stamp.jsp...rnumber=8742167
  Forum: Perseverance- Mars 2020 Rover · Post Preview: #249987 · Replies: 122 · Views: 103950

djellison
Posted on: Feb 20 2021, 12:43 AM


Founder
****

Group: Chairman
Posts: 14457
Joined: 8-February 04
Member No.: 1


QUOTE (atomoid @ Feb 19 2021, 02:36 PM) *
There must be good reason why an emptied fuel tank poses enough an explosion hazard they take measures to avoid, but seems counterintuitive, any explanation?


Yup - the 'eyes' caption is just flat out wrong - I've let them know.

As you run out of fuel you can get a mix of fuel and pressurizing gas coming through the pipelines together and bad things can happen.

tl;dr don't run a rocket dry. Bad things happen.

Shut the engines down after they've done all they need to and the problem goes away. Moreover - the longer you run those engines, the longer you need to maintain attitude to keep firing in a good direction - away from the rover. As the paper I cited earlier details - that's not trivial.

6 seconds is enough.

  Forum: Perseverance- Mars 2020 Rover · Post Preview: #249911 · Replies: 477 · Views: 263318

djellison
Posted on: Feb 19 2021, 10:10 PM


Founder
****

Group: Chairman
Posts: 14457
Joined: 8-February 04
Member No.: 1


I think the full frame is actually the whole frame from Front Left - and the wheel subframe is from the Front Right.
  Forum: Perseverance- Mars 2020 Rover · Post Preview: #249894 · Replies: 477 · Views: 263318

djellison
Posted on: Feb 19 2021, 09:30 PM


Founder
****

Group: Chairman
Posts: 14457
Joined: 8-February 04
Member No.: 1


QUOTE (Steve G @ Feb 19 2021, 12:18 PM) *
It burns its fuel until depletion


It does not do this. See Mars Science Laboratory Flyaway Guidance, Navigation, and Control System Design. Behçet Açıkmeşe et.al.

The bridle umbilical device (BUD) has built-in retraction
springs to retract the now free bridles away from the rover top deck.
Once the flyaway controller on the DS assumes control, it first
holds the current altitude for 600 ms to allow sufficient time for the
umbilical to be cut. After the requisite hold time, the thrusters throttle
up and the DS ascends vertically for a predetermined amount of time.
Then, the DS begins to execute a turn to approximately 50 deg pitch.
The DS holds this attitude with the thrusters at 60% for 4 s. The hold,
ascent, and turn take place within 2 s, which corresponds to a total
flyaway time of 6 s



There is fuel and high pressure gas still onboard when this is finished. Flyaway consumes ~20-22kg of fuel. M2020 had ~90kg of fuel remaining so there were ~70kg of fuel left on the descent stage at burnout.

To burn to depletion would be to risk an explosive event at fuel exhaustion causing a debris field the rover would be well within.

https://static.uahirise.org/images/2012/det...028401_1755.jpg < The crime scene of the MSL descent stage impact. Note the explosive nature of the scar.

The descent stage doesn't have a proper flight computer. It doesn't have it's own communications. It doesn't have it's own power generation. It doesn't have its own instruments. It doesn't have landing gear. It doesn't have enough fuel to land anyway.

This is a big discussion we all had in this place 8+ years ago. The descent stage is not a missed opportunity for a lander.
  Forum: Perseverance- Mars 2020 Rover · Post Preview: #249891 · Replies: 477 · Views: 263318

djellison
Posted on: Feb 18 2021, 03:49 AM


Founder
****

Group: Chairman
Posts: 14457
Joined: 8-February 04
Member No.: 1


That's not a map of the surface - that's a map of a plan through deep space. The spacecraft actively flies its way through entry to target the center of the ellipse. You can't translate that entry mapping image onto a surface map.
  Forum: Perseverance- Mars 2020 Rover · Post Preview: #249642 · Replies: 75 · Views: 93860

djellison
Posted on: Feb 18 2021, 02:50 AM


Founder
****

Group: Chairman
Posts: 14457
Joined: 8-February 04
Member No.: 1


MRO will be doing bent-pipe realtime relay ( which is a new feature on MRO thanks to a software update )
MAVEN will be doing canister mode recording for later return to Earth.

See pages 23 and 43 of the Landing Press Kit
https://www.jpl.nasa.gov/news/press_kits/ma...g_press_kit.pdf
  Forum: Perseverance- Mars 2020 Rover · Post Preview: #249640 · Replies: 75 · Views: 93860

djellison
Posted on: Feb 15 2021, 11:46 PM


Founder
****

Group: Chairman
Posts: 14457
Joined: 8-February 04
Member No.: 1


QUOTE (Explorer1 @ Feb 15 2021, 12:51 PM) *
any plans on MRO attempting imaging like MSL


At the L-30 briefing they said yes - infact, they're going to try and do it a little later during EDL - so you'll have the powered descent vehicle flying below the parachute and backshell.

Fingers crossed.
  Forum: Perseverance- Mars 2020 Rover · Post Preview: #249603 · Replies: 75 · Views: 93860

djellison
Posted on: Feb 15 2021, 08:53 PM


Founder
****

Group: Chairman
Posts: 14457
Joined: 8-February 04
Member No.: 1


You can thank the Presidents Day holiday for the extra sol of downlink to spend on a full frame upper tier 5x1 biggrin.gif
  Forum: MSL · Post Preview: #249597 · Replies: 990 · Views: 555597

djellison
Posted on: Feb 15 2021, 05:18 PM


Founder
****

Group: Chairman
Posts: 14457
Joined: 8-February 04
Member No.: 1


QUOTE (Sean @ Feb 15 2021, 08:14 AM) *
Browser is Brave


Yeah - I think Brave has a pretty wide swathe of WebGL issues. I'll fwd this onto the team but I doubt there's much they can do.
  Forum: Perseverance- Mars 2020 Rover · Post Preview: #249591 · Replies: 33 · Views: 34144

462 Pages V  « < 6 7 8 9 10 > » 

New Posts  New Replies
No New Posts  No New Replies
Hot topic  Hot Topic (New)
No new  Hot Topic (No New)
Poll  Poll (New)
No new votes  Poll (No New)
Closed  Locked Topic
Moved  Moved Topic
 

RSS Lo-Fi Version Time is now: 17th December 2024 - 05:44 AM
RULES AND GUIDELINES
Please read the Forum Rules and Guidelines before posting.

IMAGE COPYRIGHT
Images posted on UnmannedSpaceflight.com may be copyrighted. Do not reproduce without permission. Read here for further information on space images and copyright.

OPINIONS AND MODERATION
Opinions expressed on UnmannedSpaceflight.com are those of the individual posters and do not necessarily reflect the opinions of UnmannedSpaceflight.com or The Planetary Society. The all-volunteer UnmannedSpaceflight.com moderation team is wholly independent of The Planetary Society. The Planetary Society has no influence over decisions made by the UnmannedSpaceflight.com moderators.
SUPPORT THE FORUM
Unmannedspaceflight.com is funded by the Planetary Society. Please consider supporting our work and many other projects by donating to the Society or becoming a member.