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Juno skims the cloud tops of Jupiter

nasa.gov

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Re: Juno skims the cloud tops of Jupiter

#21

Post by orbital-decay »

ericbarrett wrote: post #7
holoduke wrote: post #4

210,000 kilometers per hour. Almost 60km/40mi per second. Amazing speed when you think about it. Wonder if there would be any time dilation noticable if the craft ever gets captured and brought back to earth.

Similarly I wonder if there was any detectable heating from kinetic interaction with dust and trace atmosphere. 60 km/sec is fast!

Not sure about the composition of atmosphere at those exact altitudes on Jupiter, but aerodynamic heating was a serious concern during Cassini's close Titan flybys, and that's "just" at ~6.3km/s max. IIRC the closest one was the T-70 at 880km; a lot of work has been done to make sure it won't tumble or overheat. (Titan's low gravity makes its dense atmosphere reach very far, so 880km is really low)

Re: Juno skims the cloud tops of Jupiter

#22

Post by arghwhat »

holoduke wrote: post #4

210,000 kilometers per hour. Almost 60km/40mi per second. Amazing speed when you think about it. Wonder if there would be any time dilation noticable if the craft ever gets captured and brought back to earth.

As a point of reference, our solar system orbits our galaxy at approximately 4 times that speed at 828 megameters per hour, so 210 megameters per second isn't that big a deal in the grand scheme of things...

Re: Juno skims the cloud tops of Jupiter

#24

Post by belter »

holoduke wrote: post #4

210,000 kilometers per hour. Almost 60km/40mi per second. Amazing speed when you think about it. Wonder if there would be any time dilation noticable if the craft ever gets captured and brought back to earth.

They are noticed in the Parker Solar Probe. At closest approach it get's to 590,000 kilometers per hour (aprox 360,000 mph)

"Parker Solar Probe passing extremely close to the Sun; what relativistic effects will it experience and how large will they be?": https://physics.stackexchange.com/questions/348854/parker-so...

Re: Juno skims the cloud tops of Jupiter

#25

Post by Cthulhu_ »

sgt wrote: post #5
pjscott wrote: post #3

In case anybody was wondering "Why is the frame rate so lousy?" the answer is that the probe only has about 325 bits per second of downlink on average. https://en.wikipedia.org/wiki/Juno_(spacecraft)

Would it be possible to extrapolate frames in between to give one smooth flyover?

And are there additional images in the probe's storage that will be transferred over the coming... years?

Re: Juno skims the cloud tops of Jupiter

#26

Post by sephamorr »

arriu wrote: post #23

It’s really a shame they didn’t put better imaging equipment on Juno. The argument being that little science would be gained from it. I’d argue secondary effects would have made it worth the weight.

You have to be careful what you ask for - I certainly like pretty pictures myself, but one of the reasons that Juno is so successful as a scientific mission is because it was kept to the barebones and managed scope so aggressively. With Juno ($1B for an outer planets mission) we got Flagship mission-quality science for a New Frontiers price. There's a good interview with Mark Wolverton on Planetary Radio that discusses how this happened.

Re: Juno skims the cloud tops of Jupiter

#28

Post by Crontab »

holoduke wrote: post #4

210,000 kilometers per hour. Almost 60km/40mi per second. Amazing speed when you think about it. Wonder if there would be any time dilation noticable if the craft ever gets captured and brought back to earth.

I've read that time moves a tiny bit slower on Earth than it does in space and that it affects satellites. I wonder how much difference there is for something like the Voyagers, which has been in space since the 70's, and us on the ground.

Re: Juno skims the cloud tops of Jupiter

#29

Post by lifeisstillgood »

Basic science is the foundation stone of the past 200 years of human progress - and if anyone out there wants to put "double the science budget just because" on their manifesto they can have my vote.

I am so glad we live in an age where this is possible, and that it is celebrated and respected.

Fantastic.

Re: Juno skims the cloud tops of Jupiter

#30

Post by _Microft »

arghwhat wrote: post #22
holoduke wrote: post #4

210,000 kilometers per hour. Almost 60km/40mi per second. Amazing speed when you think about it. Wonder if there would be any time dilation noticable if the craft ever gets captured and brought back to earth.

As a point of reference, our solar system orbits our galaxy at approximately 4 times that speed at 828 megameters per hour, so 210 megameters per second isn't that big a deal in the grand scheme of things...

Kilometer is the largest SI-prefixed variation of meter that is commonly used (among physicists that I know). I would rather suggest that you use scientific notation if you do not want to deal with large numbers of kilometers.
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