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New images of Jupiter

missionjuno.swri.edu

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Re: New images of Jupiter

#41

Post by foobarbecue »

Buttons840 wrote: post #37
lbltavares wrote: post #15

Earlier quoted context omitted.

Jupiter would need to weigh 13 times its current mass to become a brown dwarf, and about 83 to 85 times its mass to become a low-mass star [1] [1]: https://www.astronomy.com/science/ask-astro-could-jupiter-ev...

Earth's mass is something times 10^24. Jupiter's mass is 2 x 10^27. The smallest stars are 8 x 10^28. On an exponential scale, Jupiter is closer to being a star than it is to being Earth. So... maybe you could say that Jupiter is almost a star. With such loose definitions talking about astronomical scales, there's a lot of room for interpretation and exaggeration. I think the point is--in the spirit of appreciating J…

In case anyone was wondering, that something is about 6kg.

Re: New images of Jupiter

#42

Post by adolph »

KWxIUElW8Xt0tD9 wrote: post #36
CableNinja wrote: post #32

Earlier quoted context omitted.

Pretty difficult. Jupiters sphere of influence is full of radiation, meaning the sat needs a lot of shielding which makes it very heavy. Additionally, you need a lot of thrust to not only get to Jupiter, but to be able to get into a geosync orbit around a planet other than earth, so youre gonna need a lot of fuel. And finally, time... Europa Clipper just left earth, it will be 8 years before it arrives at jupiter. Th…

I was under the impression that we now know how to do low-fuel paths through the solar system using gravity. It's more a question of how long do you want to take to get where you're going.

Yes, this specific specific duration has to do with the choice of launch vehicle. (No shade for any particular program as all have different tradeoffs and I'm gratified to see the probe successfully on its way.)

The SLS option would have entailed a direct trajectory to Jupiter taking less than three years. ... The move to Falcon Heavy saved an estimated US$2 billion in launch costs alone. NASA was not sure an SLS would be available for the mission since the Artemis program would use SLS rockets extensively, and the SLS's use of solid rocket boosters (SRBs) generates more vibrations in the payload than a launcher that does not use SRBs.

https://en.wikipedia.org/wiki/Europa_Clipper

Re: New images of Jupiter

#44

Post by danparsonson »

openrisk wrote: post #33

Alien feel (and even unsettling at times). I guess we have grown used to this by now, but from the Moon landing pictures, to the Mars rovers and the various asteroid and planetary missions the objects of the Solar system are now vivid, complex and above all, "real" places.

I know what you mean - looking at planetary close-up images, I sometimes involuntarily get the feeling of what it would be like to be out there with the probe, lonely and desolate and millions of miles from home....

Re: New images of Jupiter

#45

Post by dr_orpheus »

youtubeuser wrote: post #43

Maybe silly question, but why are the pictures cropped?

Not a silly question. I don't think the images are actually cropped. JunoCam is described as a "push broom" imager [0]. The camera takes pictures as the spacecraft turns. So it's more like you are looking at a stitched together panorama and not a cropped version of a larger image.

[0] https://en.wikipedia.org/wiki/JunoCam#Design

Re: New images of Jupiter

#46

Post by dr_orpheus »

foobarbecue wrote: post #40
KWxIUElW8Xt0tD9 wrote: post #36

Earlier quoted context omitted.

I was under the impression that we now know how to do low-fuel paths through the solar system using gravity. It's more a question of how long do you want to take to get where you're going.

If you want to go faster, you need more fuel, and eventually you max out the biggest rocket available. Clipper is the most massive planetary probe ever-- they had to use falcon heavy in fully expendable mode to get it up there.

Yep, for reference Europa Clipper is 6,065 kg [0]. It is an absolutely massive interplanetary probe. It is getting close in size to some of the largest GEO communication satellites. And to get it out to Jupiter they definitely need some of the gravity assist trajectories.

On the opposite end of the spectrum, New Horizons was only 478 kg [1] and still holds the record for the fastest thing ever launched from Earth. It also did a gravity assist flyby around Jupiter and it still took 9 years to get to Pluto.

[0] https://en.wikipedia.org/wiki/Europa_Clipper

[1] https://en.wikipedia.org/wiki/New_Horizons

Re: New images of Jupiter

#47

Post by Aachen »

foobarbecue wrote: post #39
Aachen wrote: post #23

These come from Juno, a mission sent in 2011 and orbiting Jupiter since 2016. Must say it wasn't really on my radar anymore, but looking at the timeline on Wikipedia, it's still going around and getting close ("perijove") every month and a week or so, at an ever-increasing longitude https://en.wikipedia.org/wiki/Juno_(spacecraft)#Timeline The planned end of the mission is in about a year. The camera was "included in…

Yeah, they had to fight so hard to get that camera on there! It was not included in the initial designs since it wasn't necessary for the science objectives.

Makes me wonder what it costs to send a "simple" camera along. Factors that make it probably not so simple: even 200 grams of camera (and extra solar panels to supply +10W while operating) probably costs many thousands of euros in rocket fuel and emission taxes. The engineering time to properly fixate it onto the spacecraft, integrate the software, and test the whole thing cost probably a few ten thousands in salaries. Radiation may be a big problem for what's otherwise off-the-shelf hardware, that might mean the hardware costs much more (tens of thousands instead of a couple hundred euros potentially?) and gets significantly heavier from shielding, but I wouldn't know how much. Is that about right, am I missing something major and/or am I off on orders of magnitude somewhere?

Re: New images of Jupiter

#48

Post by ClumsyPilot »

foobarbecue wrote: post #39
Aachen wrote: post #23

These come from Juno, a mission sent in 2011 and orbiting Jupiter since 2016. Must say it wasn't really on my radar anymore, but looking at the timeline on Wikipedia, it's still going around and getting close ("perijove") every month and a week or so, at an ever-increasing longitude https://en.wikipedia.org/wiki/Juno_(spacecraft)#Timeline The planned end of the mission is in about a year. The camera was "included in…

Yeah, they had to fight so hard to get that camera on there! It was not included in the initial designs since it wasn't necessary for the science objectives.

> It was not included in the initial designs

That’s why NASA is poor and pentagon is rich.

To me as a taxpayer, if there are no cool pictures, it doesn’t exist.

If they were politically shrewd, camera would be the biggest instrument.

And the next probe that will dive into the sun would carry the bullet that killed Kennedy or a shot off piece from Trump’s ear.

Re: New images of Jupiter

#49

Post by meowster »

Ma8ee wrote: post #38
vasco wrote: post #28

Earlier quoted context omitted.

It doesn't care about us, and we don't need to "care" for it, it's going to be fine without us. What we don't do is care for ourselves, which is what you're really saying, self-preservation. The earth doesn't give two shits if it's 50 degrees warmer. You can't even say it's to protect life, because some forms of life will do way better in a warmer planet too. The universe / nature is gnarly already, much more than we…

I can't help find such edgy cynism nothing else than juvenile. Yeah, sure, in the end nothing matters and the universe doesn't give a fuck about you. And life on earth is just an accident, and that intelligence and consciousness exists here for a very brief time on the universe's path to heath death doesn't matter at all. Except of us poor conscious beings who find joy in being alive and actually have the capacity to…

> us poor conscious beings who find joy in being alive and actually have the capacity to marvel, because it is marvellous that we can, and we should.

> And I care that it is us who inhabits the earth, and not slugs.

That's not mutually exclusive with the comment you were replying to.

I agree with both of your comments except for your opinion that the first comment is "edgy cynism" and "juvenile".

Re: New images of Jupiter

#50

Post by latexr »

JoeAltmaier wrote: post #29

Juno was something about radar - penetrating the cloud layers to see what was below. In college my son worked on the FFT engine that processed the radar data. He has code circling Jupiter!

That would be a hilarious (and confusing) bumper sticker. When other parents say “my son is an honour student” you can smugly reply “yeah, but does he have code circling Jupiter?”

Congratulations, by the way. I’m being (trying to be) funny but I genuinely think that is cool and a reason to be proud.

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