MSL Approach Phase Options

[Guest_Oersted_*]

Odyssey in safe mode again, acc. to Paolo (JPL rover driver) in the Opportunity forum...

[climber]

Pre_landing telecon tonight at 10AM Pacific: http://www.nasa.gov/home/hqnews/2012/jul/H...Prelanding.html
I'm feeling like I'm back to december 2003 for Spirit's prelanding telecom
We're getting close

[jmknapp]

Pre_landing telecon tonight at 10AM Pacific: http://www.nasa.gov/home/hqnews/2012/jul/H...Prelanding.html
I'm feeling like I'm back to december 2003 for Spirit's prelanding telecom
We're getting close

Here's the Spirit pre-landing press conference, held on the day of the landing:

http://www.c-spanvideo.org/program/179768-1

[ElkGroveDan]

Pre_landing telecon tonight at 10AM Pacific:

Don't do that to me before I have had my morning coffee.

[akuo]

Missed the press conf live, but its already visible as a recording here: http://www.ustream.tv/nasajpl

Watching the recording at the moment, but I find something strange in the released information and images. The press kit specifies the landing ellipse as 20x25km, and I remember the graphics before having a lot more circular ellipse. Now, looking at the press kit and some released images, I again see a quite elongated ellipse:
http://www.nasa.gov/mission_pages/msl/mult...a/pia15690.html

There are no scale there, so its difficult to understand the scale of the ellipse. Anyway, has the predicted ellipse become more elongated, and if so, is it more or less accurate than before?

[RoverDriver]

20x25 Km is the nominal size for the ellipse. I don't have the most recent values but I believe it is in the 21x7Km range. I will find out and edit this post.

Paolo

[Phil Stooke]

The ellipse was reduced in size a few weeks ago:

http://mars.jpl.nasa.gov/msl/multimedia/images/?ImageID=3855

Phil

[akuo]

Ok, I haven't followed the official MSL site keenly enough:)

7km wide ellipse, that is really excellent.

[jmknapp]

Missed the press conf live, but its already visible as a recording here: http://www.ustream.tv/nasajpl

Thanks for the link--missed it too.

[djellison]

21 x 7km is the size I used for the artwork

[jmknapp]

An important item from the press conference was that due to a malfunction on Odyssey, the first indication of a successful landing might not be until several hours after the landing. Odyssey would have been positioned to receive UHF transmissions from MSL and relay them immediately ("bent pipe" telemetry) , but if Odyssey can't be positioned as desired due to the reaction wheel problem, then MRO will store and forward the data 3-4 hours later. Mars Express will be below the horizon at landing, as will Earth. Odyssey could contact MSL on its next orbit about 1-2 hours after landing.

[stewjack]

Odyssey could contact MSL on its next orbit about 1-2 hours after landing.

That is the way I understood it from the press conference, however a BBC article suggests something different.
---
Nasa may miss Curiosity Mars rover's landing signal
By Jonathan Amos Science correspondent, BBC News

As things stand, Nasa could be waiting on Odyssey to make a late pass of the landing site, perhaps five to 10 minutes after the rover's planned touch down.

This (MSL Landing) is projected to be 22:31 PDT 5 August; .....snip...
"If Odyssey is not able to be moved and it still remains late, that means it will fly over [Curiosity] after the spacecraft has landed, and we presumably will [then] be able to see transmissions from it. It would be somewhere between 22:35 and 22:40 PDT," explained Pete Theisinger, the rover project manager at Nasa's Jet Propulsion Laboratory in Pasadena, California.
---
Personally, I (in the CDT time zone) think I should plan for an all-niter.

Jack

[brellis]

Dang it, I'm already half way through the first of the three bags of pistachios I bought for the PlanetFest thingy. Good thing there's a Trader Joe's on the way!

[nprev]

Just for clarity's sake, we're talking about delayed return of the full EDL data set as the worst-case scenario in this situation, correct?

Would hate to lose any of that; you only get one shot per landing to get it, and it's invariably quite valuable for future mission planning.

[djellison]

The baseline plan was...

X-Band DTE
Tones up until just after 'chute deployment in the MER stule

UHF
Bent pipe relay 8kps via Mars Odyssey
Store and Forward from Entry to Landing 8kbps via MRO ( that we would get at about landing +4 to 5hrs or so )
And partial carrier only via MEX

Now - the only change is the bent pipe 'live' 8kbps telem via MODY is in jeopardy.

I bet they'll find the time between now and landing to re-tweak MODY's orbit, burn a bit of prop, and get it back in place for bent-pipe relay. There's several decades of prop margin onboard.