Flight Question Aero-braking at Jupiter

[Matrix Aran]

Hello folks. First off forgive me if I'm asking the impossible, while I've been a long time lurker on these forums and have toyed with Orbiter on and off for the last year, I still see myself as much the novice and many things still go right over my head. Still I'm able to get to the moon and back, and make rather precise landings on realistic-ish settings.

I've been experimenting with many new things the last few weeks including missions to Mars and Jupiter, most of these in an XR2 with the apropriate fuel settings/cargo.

While I can with some practice reliably aerocapture Mars, I've wanted to experiment with doing the same at Jupiter and thus saving on fuel. Try as many plans as I might I can't seem to find a way to arrive at Jupiter and slow down while in the atmosphere without shooting right out the other side or burning the ship into a pile of molten slag.

My question is, does anyone have any experience with aerobraking/capture at Jupiter? Is it possible in an XR2, and if so, what are the specifics that I'd want to be looking at for a non-crispy, safe ride?

 

[Cairan]

Aerobraking at Jupiter is, IMHO, not possible with the XR2 or any other vessel designed for more benign reentries. I never ever managed to aerobrake or aerocapture at Jupiter. Ever.

However, Saturn has something Jupiter lacks: an orbiting moon (Titan) with a very thick atmosphere and low gravity... That's aerocapture paradise! You can intercept Titan with a relative velocity as low as 4.5 km/s if you do it right... Doing so enables you to get in orbit of Saturn also, since Titan orbits it... so you kill two birds with one stone! See this thread I posted in some cool information about a trip from Earth to Titan via Mars and the Moon...

http://www.orbiter-forum.com/showthread.php?t=14708

 

[Wishbone]

I tried aerobraking at Jupiter with an Arrow. Took me a few lives to get it right. With an XR2 it is, as you say, crispy and iffy.

 

[K_Jameson]

My question is, does anyone have any experience with aerobraking/capture at Jupiter? Is it possible in an XR2, and if so, what are the specifics that I'd want to be looking at for a non-crispy, safe ride?

I tried a couple of times with the default Delta Glider, testing the concept for my Galileo II automatic mission (see the thread). It works very well at an altitude of around 800 km, where you can perform a "soft" aerobraking for the correction of an already acquired orbit (not an aerocapture from an hyperbolic trajectory, i think)... at lower altitudes with more violent atmosferic drag, i suppose that the environment is too extreme for a winged vehicle as the XR2...

 

[Tacolev]

If you're being realistic about your craft's heat-loading, you should also remember that your poor UMMUs will be subjected to jupiter's excessive radiation environment. This is, however, a good reason to shoot for a very loose capture, so your new apogee will wind up at about the distance of ganymede or callisto where a moderately shielded spacecraft could go about its operations.

I've had some success braking into orbit with what would amount to a survivable re-entry using some of the aeroshell'd vehicles from "world of 2001." Obviously no complicated damage model to confirm it, though. Shoot for 450-500 klicks for your perigee and experiment from there.

 

[Wishbone]

Going to the innards of Jupiter system with UMMus is merciless in the first place, aerobraking or not. Nuclear sunburn, vomiting and painful death... not my idea of happy space exploration.

 

[K_Jameson]

If you're being realistic about your craft's heat-loading, you should also remember that your poor UMMUs will be subjected to jupiter's excessive radiation environment.

true... true...
the radiation dosage is fatal...

 

[Matrix Aran]

Thank you all for your replies. looks like I'm going to have to change my vacation plans then. Hopefully I can still get a flight to Titan!

 

[Pipcard]

In 2010, the Leonov was aerobraking around Jupiter and was really skimming the really thin, almost invisible part of the atmosphere.

 

[elephantium]

Going to the innards of Jupiter system with UMMus is merciless in the first place, aerobraking or not. Nuclear sunburn, vomiting and painful death... not my idea of happy space exploration.

Meh. You're only doing manned flights to Jupiter with magic spacecraft anyway, so what's the harm in assuming better radiation shielding systems along with an impossibly efficient rocket engine?

 

[Matrix Aran]

Meh. You're only doing manned flights to Jupiter with magic spacecraft anyway, so what's the harm in assuming better radiation shielding systems along with an impossibly efficient rocket engine?

I'm tempted to agree, but in any case the XR2 doesn't seem to be able to generate a meaningful amount of braking, in the short available time, without suffering some sort of structural failure.