Mars Recon Orbiter Nearing Mars Orbit

DarkNemesis618 writes "The Mars Reconnaissance Orbiter, launched 12 August 2005, has nearly completed its 7 month journey to the Red Planet. At 9:24 pm GMT, the MRO is scheduled to fire its thrusters to slow it down enough to enter Mars orbit. NASA scientists are concerned about this final step for the orbiter as Mars has a history of 'swallowing' probes, orbiters, and landers sent to the Red Planet. What makes it more difficult is the delay time between NASA computers on earth and computers on board the orbiter. There is about a 12 minute delay between when data is sent from Earth to the time the orbiter's receivers pick it up, and vice versa. Because of this, onboard computers will handle the burn which adds to the risk."

Comments

Computerized burns

[donour]

Haven't orbital burns been computer controlled since the beginning human spaceflight. If I remember correctly, the manual burn during the Apollo 13 mission was not routine.

It isn't really a burn, but aren't all space shuttle landing corrections done by machine as well. I seem to remember reading that the shuttle had only been landed by hand once.

Re:Computerized burns

[AKAImBatman]

All the apollo lunar landings were flown manually for the last minute or so.

Actually, Armstrong took manual control from the computer during the Apollo 11 landing. This was due to several program errors (the radar switch was in the wrong position) as well as mistakes in automatic guidance. Armstrong was advised to abort at one point, but chose to land the Eagle anyway.

My recollection is that shuttle landings are generally flown manually.

Pretty much everything up until the landing gear is released is automatic. The Shuttle could be landed on automatic, but the engineers made an intentional decision to make the landing gear deployment a 100% manual process. The reason for this is that the landing gear cannot be stowed in flight once it is deployed. Should a computer error occur, premature deployment of the gear could cause a failed reentry or undershoot of the intended landing zone.

The Russians, OTOH, had no qualms about automating the landing. The Buran Space Shuttle flew once with no crew aboard, and safely landed on full automatic.

Re:Something else they are worrying about

[MichaelSmith]

They won't know with absolute certainty that everything is ok until the time has passed and the probe comes around the planet.

Its a pity they couldn't organise a relay. There are two spacecraft in mars orbit right now which can relay comms from the ground. You would think that with a few software changes and a bit of planning one of them would be able to at least record telemetry from the spacecraft as it did the burn.

Re:Success!!!!

[DestroyAllZombies]

Well, thanks! I'm in the mission control area right now, so here's another score for slashdot. Of course the next six months of aerobraking will be the hardest, but being in orbit is fantastic.