"Curiosity" - Launch 7.30AM EST (Live)

http://mars.jpl.nasa.gov/msl/mission/timeline/launch/watchonline/

by dananjaya86 • 15 years ago

62 22 15 years ago

mars.jpl.nasa.gov

In case you haven't seen how this thing lands, watch the link below. It's really so amazing how this is entirely automated and executed so flawlessly.

http://www.youtube.com/watch?v=BudlaGh1A0o

forbes3• 15 years ago

It will be amazing when it has happened, yes. (Not being snarky - I think it will happen as planned.)

willyt2• 15 years ago

Why is the heat shield jettisoned 7km above the surface exposing the rover to the atmosphere while its travelling at over 500kph? Does anyone have any insight into the design decisions in this landing sequence?

trothamel• 15 years ago

http://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/2009000...

is a paper written by the engineers who designed the system, explaining these decisions. I suspect that the reason is that - in Mars's thin atmosphere - 500kph isn't as much pressure as it would be on Earth. (The constraint appears to be that the heat shield needs to fall away.)

I found the way MSL detects landing to be clever. Instead of a switch or sensor, it records the throttle setting required to descend at a constant speed. When that setting drops (for a sufficient time), the rover must have touched down.

plusbryan• 15 years ago

Is this the simplest sequence of events and machinery they could come up with the achieve the landing? There are a lot of motors, sensors, and propulsion engines that could fail.

sehugg2• 15 years ago

At 775 kg it's too heavy to do the bouncy thing like Pathfinder.

profquail• 15 years ago

7:30am? The official launch blog says 10:02am (EST):

http://www.nasa.gov/mission_pages/msl/launch/launch_blog.htm...

elliottcarlson• 15 years ago

    November 26, Saturday (Launch Day)

    7:30 a.m. EST (4:30 a.m. PST) - NASA TV launch commentary coverage and launch blog.
    10:02 a.m. EST (7:02 a.m. PST) - MSL's Launch
    12:30 p.m. EST (9:30 a.m. PST) (approximately) - Post-launch News Conference
    12 - 5 p.m. EST (9 a.m. - 2 p.m. PST) - Scientist in Action for MSL (Education Channel)

forbes3• 15 years ago

The coverage started at 7:30am. This is the first time I have watched one of these and I must admit I am pretty excited.

forbes3• 15 years ago

At T-4 minutes they hold for 10 minutes and the commentary said this was planned beforehand. Does anyone know why they don't just plan to launch 10 minutes later without the 'hold'?

ramidarigaz• 15 years ago

There are very specific things that have to happen at certain points during the countdown. I expect that the plan to have the 10 minute hold was created after the software was configured for all the last minute tests. Reconfiguring all the software would be impossible right before the launch, so instead, they stop the clock. Stopping the clock is not unusual, and all the software that works off the clock is built to deal with a hold.

Sharlin• 15 years ago

Basically, holds are used to give the personnel some breathing room to make checks and ensure everything is okay (and presumably to relax a bit, go to toilet, and other human necessities). If something does not check out, a hold could be extended to debug the problem - on the other hand, when the clock is running, the schedule cannot be changed because many things are preprogrammed in the launch vehicle and the spacecraft to occur at certain clock ticks.

demallien• 15 years ago

The pre-programmed holds (as opposed to unplanned holds) exist so that if there were any unexpected temporary hitches in the launch sequence, there is still time to make the launch window. Imagine for example that you have a 1 minute launch window, and a slower than expected fuel pump means that it takes 5 minutes longer to top off the fuel tanks. Well, you just missed your entire launch. Stand everyone down, and put the spacecraft back into standby before trying again tomorrow. If you have a planned hold, you simply reduce the planned hold time, and you can still hit the launch window.

The hold is also used as a sync point between all of the different activities that have to be completed at certain points in the launch preparation. For example, at the t-4 hold for the Curiousity launch, they needed to pass the go/no-go from the entire team. If one team had been running late up till that point it wasn't a problem, the other processes just entered the hold earlier. Once the last hold has been cleared, all of the remaining processes have to stay synchronised.

Figs• 15 years ago

If you're having trouble getting it to load, you might try here instead: http://www.ustream.tv/nasajpl

johnbatch• 15 years ago

also a mobile feed (Mobile optimized, lower quality) at http://www.ustream.tv/channel/nasa-mobile

ugh• 15 years ago

Thanks for the reminder! And just in time, one minute before launch.

dananjaya86• 15 years ago

UPDATE: MSL is in good health and en route to Mars. Landing anticipated: 5 August 2012 http://www.jpl.nasa.gov/news/news.cfm?release=2011-361

"Curiosity" - Launch 7.30AM EST (Live)

Related Stories