Lunar Reconnaissance Orbiter Launch, Launch through Orbit Discussion Options

[Juramike]

Launch video (lotsa rocketcam with voiceover + sound from ground) on Youtube:

http://www.youtube.com/watch?v=j-5t4de6jjI...feature=related

[SpaceListener]

About the speed trayectory of LRO/LCROSS from Earth toward Moon, I am still trying to learn and understand its evolution speed. However, I know that the minimum velocity required to escape from Earth gravity is around 11.6 kp/s and I have noticed thru the other source of information that the spacecraft was reducing its speed from 5 kp/s at about 35,000 km from Earth, 4kp/s even further from Earth. Then I tought that the LRO/LCROSS didn't reach the 11.6 kp/s to escape from Earth gravity in its way toward to Moon but at lower speed...

Then I realized the spacecraft speed will be reducing to the minimum speed until the Selene gravity captures it.

Is that my tought correct? Thanks for any comments.

[Hungry4info]

Is that my tought correct? Thanks for any comments.

Mostly, but when the spacecraft gets closer to Selene, it's gravity will cause LCROSS and LRO to accelerate (as they're then falling toward Selene).

[Guest_Zvezdichko_*]

According to NASA-Twitter, the midcourse correction burn was completed successfully. Also they have switched on the Russian instrument - LEND.

[SpaceListener]

Mostly, but when the spacecraft gets closer to Selene, it's gravity will cause LCROSS and LRO to accelerate (as they're then falling toward Selene).

Thanks, so, the conclusion is that the spacecraft LRO/LCROSS didn't reach the speed of Earth's escape gravity since its speed is already decreasing on its way toward to the Moon.

When the spacecraft will start to pick up the speed? I tought it would be when the spacecraft is already traveled 5/6 of Earth-Moon distance (320,000 km)?

[ugordan]

LRO/LCROSS didn't reach the speed of Earth's escape gravity since its speed is already decreasing on its way toward to the Moon.

The highest speed it had was just when the Centaur shut down after lunar injection. It was then at 300 km altitude and at that point the escape velocity would be slightly lower than the quoted one of 11.2 km/s (which assumes you start from the ground). To reach moon you need something close to that, Apollo lunar flights for example ended burns at roughly the same altitude and at that time were going at 10.8 km/s and I assume that's roughly the same velocity LRO/LCROSS had.

[belleraphon1]

That rocket cam shot rising through the clouds was awesome!

Awesome indeed.

Have to admit I am getting all Moonie and nostalgic for the 60's unmanned missions that preceeded APOLLO.
And APOLLO.

LRO/LCROSS are going to be very cool missions...

NASA LRO Webcast
http://www.youtube.com/watch?v=yruN1iqeorw...292&index=7

LRO data will be made available to Google Moon. LCROSS October impact imaging data will be supplied live - like Ranger 9
in 1965.

GO LRO for LOI!

GO LCROSS... long wait til October...

Craig

[zeBeamer]

Hello guys,
thought I would register now that LRO has launched successfully

Another cool video is on ULA's website (http://www.ulalaunch.com/)
direct link: http://www.ulalaunch.com/launch/LRO/LROLCR...hHighlights.wmv

I was lucky enough to be invited to the launch, and see it!
One of the pictures I took :

By the way, LRO has a blog with many updates about how it's doing and what's next:
http://lroupdate.blogspot.com/

[Guest_Zvezdichko_*]

Great!

I'm a little worried about the power drop. It's insignificant, but anyway..

[Phil Stooke]

The one thing I'm looking forward to more than anything else? Matching LROC images to the Soviet era map of the Lunokhod 1 route, to locate the old rover and its landing stage.

Phil

[Hungry4info]

The one thing I'm looking forward to more than anything else? Matching LROC images to the Soviet era map of the Lunokhod 1 route, to locate the old rover and its landing stage.

To what precision are these landing sites known? Will it be a problem for LRO?

[Phil Stooke]

We don't know exactly where it is - that's why i'm looking forward to it. There is no doubt about where the Apollos and most Surveyors are, but the Lunas are not precisely located. Luna 9 and 13 will be very hard to find, with tens of images needed to cover the uncertainty ellipses. And if they are imaged, they may not be very easy to identify among the rocks. But for Lunokhod 1, there is a candidate site about 5 km from the tracking position which might be it. Only one or a few images would be needed to search for it.

Phil

[Guest_Zvezdichko_*]

Just to compare - we still haven't located Mars Polar Lander, Beagle 2, Mars 6 and Mars 3. I expect we'll be searching Luna 9, 13 for years.

[zeBeamer]

the positions of Luna 17 and 21 (or rather, their Lunokhod rovers) are fairly well known, from Lunar Laser Ranging (mostly used to monitor the position of the Apollo retro-reflectors). I think Luna 21 is the least constrained of the two.

[Phil Stooke]

No, it's the other way round, though some web sources have it wrong. Lunokhod 1 has not been detected with the laser since early in the mission, in 1970. Lunokhod 2 gives a weak reflection but can be used today. A search for Lunokhod 1 is being undertaken through JPL but the full lat-long-range space has not been sampled and could take quite a while, even assuming the reflector is usable. There is at least a 5 km uncertainty on Lunokhod 1's location, but as I said there is a candidate location (made by matching the Lunokhod 1 route map to the best images of the site, which are not very good). I hope the candidate position is correct, because I suggested it, but wherever it is it will be good to have it at last.

Phil