Gravity assist like a pro (Rosetta mission)

[Scramble]

Came across this video today, which shows how several Earth/Mars gravity assists were used for the Rosetta mission to rendezvous with a comet later this year. Yes I know it is not Kerbal, but looking at the animation it might as well have been, so I thought it belonged in the general discussion thread.

After watching this, my current ad-hoc interplanetary no-gravity-assist KSP maneuvers feel very simplistic ...

[regex]

After watching this, my current ad-hoc interplanetary no-gravity-assist KSP maneuvers feel very simplistic ...

In real life we have Real Life Physics that make such things much more possible. We can also be much more precise than in KSP. We also have to deal with the fact that most real life rockets have a payload fraction somewhere in the 2~3% range (IIRC) which makes launching massive craft with enormous amounts of fuel quite tough, so maneuvers like this are necessary for successful missions.

[Xaiier]

So it breaks into solar orbit, swings past the earth, swings past mars, swings past the earth, passes an asteroid, swings past the earth, passes by an asteroid, and then meets up with a comet 4km wide after 12 years.

I do not even want to think about the calculations necessary to set all that up to that much precision.

[Thomas988]

Scott Manley

Its time to make a video

[toric5]

ive got something like this predicted in maneuver nodes, but alas, floating point errors make it hard to even chain 2 assists together outside of maneuver nodes.

[Luckless]

Is this not a multi-burn mission? It was my understanding that for each assist there were 2-3 adjustment burns to correct flight path to hit their gravity assist target time-position. You can still do very similar things in KSP, the numbers just fudge a little more, but they're technically easier to calculate due to the two-body physics.

[Kasuha]

Corrections are necessary. The trajectory is affected by solar storms, magnetic influences, by sunshine - the brightness of the probe's paint affects how much it is pushed by solar light - and even by local heat anomalies on the probe. There's no way to calculate all that precisely in advance. But these corrections may be very small if done at the right moment.

[SuperBigD60]

I wonder if the lander will have the same trouble as we do landing on Gilly

[SpaceSphereOfDeath]

I wonder if the lander will have the same trouble as we do landing on Gilly

Landing on gilly is easy.

Sorry, not landing, it's so small I just DOCK WITH IT

Edited January 17, 2014 by SpaceSphereOfDeath

[SuperBigD60]

Landing on easy is easy.

Sorry, not landing, it's so small I just DOCK WITH IT

right, my point

[SuperBigD60]

Also

Scott Manley

Its time to make a video

He already has

[Kasuha]

I wonder if the lander will have the same trouble as we do landing on Gilly

May have worse. Gilly is not flinging stones and blowing gas at us when we're getting close.

[CalculusWarrior]

Landing on gilly is easy.

Sorry, not landing, it's so small I just DOCK WITH IT

I think when you take off from Gilly, you're not rising above its surface, your engines are pushing it away.

[Specialist290]

Shuffling this over to the Science Labs, since it's discussing a real-world mission. Carry on

[Vahal]

I hope Rosetta will wake up well, 18h30 we will know if we have to send a prince to wake up her

[Luis]

I wonder if the lander will have the same trouble as we do landing on Gilly

It's actually worse. The Philae lander uses thrusters to accelerate its descent, and then thrusters to hold itself on the surface while it fires a harpoon into the comet to anchor itself in place.

http://nssdc.gsfc.nasa.gov/nmc/spacecraftDisplay.do?id=PHILAE

[StainX]

Best Video about a mission ever :

http://www.youtube.com/watch?v=wxJGaFqWJc0

So wake up, rosetta! Wake up and collect some Science!