MRO MOI Events Timeline, Time Zone Friendly |
MRO MOI Events Timeline, Time Zone Friendly |
Mar 10 2006, 10:38 PM
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#46
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Member Group: Members Posts: 311 Joined: 31-August 05 From: Florida & Texas, USA Member No.: 482 |
2225 GMT (5:25 p.m. EST) IN ORBIT! The Mars Reconnaissance Orbiter is truly an orbiter now after successfully swooping into orbit around the Red Planet today, mission control confirms! WAW MRO IS ALREADY IN ORBIT Rodolfo Wahoo! I guess it's better to slightly underburn than overburn, since the aerobraking seems to have more variables to it, and it's always better to have more fuel than less fuel to correct the orbit. I'd imagine this won't add any extra time to the 6 month trim manuvers? Time to celebrate another great day on mars! At this rate, JPL will need to add traffic control operations for mars. |
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Mar 10 2006, 10:53 PM
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#47
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Member Group: Members Posts: 178 Joined: 13-September 05 Member No.: 498 |
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Mar 10 2006, 10:53 PM
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#48
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Newbie Group: Members Posts: 6 Joined: 10-March 06 From: France Member No.: 698 |
I can breathe again!
Congratulations to the JPL for another amazing mission!! 3 orbiters! 2 rovers!! Bravo! |
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Mar 10 2006, 10:55 PM
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#49
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Founder Group: Chairman Posts: 14433 Joined: 8-February 04 Member No.: 1 |
Burn time 1641 seconds vs 1606 expected. 1000.48 m/s compared to 1000.36m/s expected.
So burn performance 97.87% of nominal, but actual Delta V 100.012% of predicted. i.e. yes - the burn was a little under the mark, but the onboard sequence saw this, worked off the Delta V, and terminated the burn according to the accumulated Delta V hitting the right mark. Doug |
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Mar 10 2006, 11:16 PM
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#50
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Senior Member Group: Members Posts: 1281 Joined: 18-December 04 From: San Diego, CA Member No.: 124 |
M-R-O-O-O-o-o-o-o!
-------------------- Lyford Rome
"Zis is not nuts, zis is super-nuts!" Mathematician Richard Courant on viewing an Orion test |
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Mar 10 2006, 11:22 PM
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#51
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Member Group: Members Posts: 813 Joined: 8-February 04 From: Arabia Terra Member No.: 12 |
Would be nice to have a Mars visualisation thingy that shows the locations of all four orbiters and two rovers.
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Mar 10 2006, 11:47 PM
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#52
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Member Group: Members Posts: 311 Joined: 31-August 05 From: Florida & Texas, USA Member No.: 482 |
Burn time 1641 seconds vs 1606 expected. 1000.48 m/s compared to 1000.36m/s expected. So burn performance 97.87% of nominal, but actual Delta V 100.012% of predicted. i.e. yes - the burn was a little under the mark, but the onboard sequence saw this, worked off the Delta V, and terminated the burn according to the accumulated Delta V hitting the right mark. Doug Excellent update! Thanks, Doug. I suppose this implies the aerobraking experienced less friction than anticipated, since the burn went longer than expected? |
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Mar 11 2006, 12:54 AM
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#53
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Founder Group: Chairman Posts: 14433 Joined: 8-February 04 Member No.: 1 |
MOI and aerobraking are very seperate. The difference wasnt anything to do with aerobraking, I think it was simply a slight underperformance by the engines, and the sort of underperformance you only notice if you have a really long burn ( i.e. much bigger than TCM1 was).
First post in this thread updated with all the info from the 0030 conf. We now have 6 spacecraft at work at Mars, that is a great thing. Doug |
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Mar 11 2006, 12:55 AM
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#54
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Member Group: Members Posts: 134 Joined: 13-March 05 Member No.: 191 |
MRO isn't aerobraking yet. MOI took place outside the atmosphere (although Mars atmosphere does extend a long way, but very tenuously. The longer burn was due to the engines underperforming very slightly. Whether that was because of less thrust per unit of fuel or less fuel per unit of time is not clear yet.
EDIT: heh, knew someone would answer before me. Zurek made a poignant point at the press conference, I thought. MRO has now completed the recovery of the loss of Mars Observer, whose instruments have been reflown on MGS, MCO (whose lost instruments have also been recovered), MODY and now MRO. Space science teaches patience. |
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Guest_Sunspot_* |
Mar 11 2006, 01:00 AM
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#55
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Guests |
How many journalists attended the press conference lol ?. Hmmmm we really need to send someone from this forum to ask questions.
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Mar 11 2006, 01:14 AM
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#56
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Senior Member Group: Members Posts: 1636 Joined: 9-May 05 From: Lima, Peru Member No.: 385 |
4 orbiters and 2 landers operating at mars at the same time ! What a pleasant day ! -- Rakhir Maybe there are 6 orbiters including two Vikings are still looping on Mars, aren't they? Rodolfo Post-edit Viking I is still orbiting around Mars at 320 x 56,000 km and it will crash on 2019. Viking II is still orbiting around Mars at 302 x 33,176. The other present orbiter is Mariner 9 until the year 2022. |
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Mar 11 2006, 01:14 AM
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#57
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Member Group: Members Posts: 510 Joined: 17-March 05 From: Southeast Michigan Member No.: 209 |
Sounds good to me - how would UMSF go about getting press credentials so we can dispatch "cub reporters" to various events? Much ado was made about the presence of bloggers at the political conventions during the 2004 US presidential campaign, and how this "Internet" thing was the wave of the future for journalism.
Anyhow, congratulations to all on the MRO team for a successful MOI. I can't wait for the images to start coming down! -------------------- --O'Dave
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Mar 11 2006, 06:57 AM
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#58
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Member Group: Members Posts: 624 Joined: 10-August 05 Member No.: 460 |
From JPL Horizons, I prefer Orbiter UTC, so no Earth-received, no time zones, longitudes are areocentric: 2006-03-10 21:21:14, alt = 1000 km, lat = 73° S, lon = 285° E 2006-03-10 21:22:03, alt = 900 km, lat = 76° S, lon = 282° E 2006-03-10 21:22:57, alt = 800 km, lat = 80° S, lon = 278° E 2006-03-10 21:23:55, alt = 700 km, lat = 83° S, lon = 268° E 2006-03-10 21:25:02, alt = 600 km, lat = 86° S, lon = 232° E 2006-03-10 21:26:21, alt = 500 km, lat = 85° S, lon = 155° E 2006-03-10 21:28:09, alt = 400 km, lat = 78° S, lon = 130° E 2006-03-10 21:31:20, alt = 329 km, lat = 63° S, lon = 120° E This was a braking manauver, the engine underperformed by 2%, but the approach was 71 km closer than the nominal target (400 km)? The delta V was returned to almost exactly nominal by burning longer, but I do not understand why this would result in a lower-than-expected altitude. (?) What am I missing this time? |
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Mar 11 2006, 07:42 AM
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#59
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Senior Member Group: Members Posts: 2517 Joined: 13-September 05 Member No.: 497 |
What am I missing this time? 1) The post you referenced was made before MOI even happened. 2) Horizons is using a trajectory that is weeks old. 3) I have no idea if "Orbiter" is propagating the elements from Horizons correctly anyway. -------------------- Disclaimer: This post is based on public information only. Any opinions are my own.
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Mar 11 2006, 11:05 AM
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#60
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Senior Member Group: Members Posts: 2488 Joined: 17-April 05 From: Glasgow, Scotland, UK Member No.: 239 |
Maybe there are 6 orbiters including two Vikings are still looping on Mars, aren't they? Rodolfo Post-edit Viking I is still orbiting around Mars at 320 x 56,000 km and it will crash on 2019. Viking II is still orbiting around Mars at 302 x 33,176. The other present orbiter is Mariner 9 until the year 2022. Rodolfo: There may be some Soviet vehicles still there, too. I doubt if they've all decayed so soon! Bob Shaw -------------------- Remember: Time Flies like the wind - but Fruit Flies like bananas!
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