If we were to orbit low over Jupiter, would we have an appreciation for its huge size?

Define "we". If humans could hypothetically fly in a low orbit?

It's an interesting question. Earth is 7,500 miles in diameter, and Jupiter is 89,500 miles in diameter-large enough to hold 1300 Earths inside it. I marvel at the Great Red Spot, thunderstorms that are as large as a continent, and lightning 1,000 times stronger than Earth's.

I can say **I** have an appreciation for its size. I can't speak for anyone else, though. [-X :wink:

Jupiter is one fat cat....
89,500 miles diameter x 3.12 = 281,030 miles circumference.
281,030 / 9.814 rotation hours = 23,635 mph surface rotational speed.
Now, that's cooking with gas compared to our earth's "idle speed" of 1,000 mph.

If one were orbiting at 300,000 miles from its center at the shuttle's speed of 17,500 mph, well, it'd take a tad over 16 hours to circumvent the planet.

I think it depends on how high up you are; If you were far enough out, it wouldn't look any bigger than Earth does.

Of course, I have an appreciation for its size already, so this would just be beating you over the head with it.

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Unfortunately, we're down to about 17 ounces of the highly unstable stuff that does.

I'd think you'd be able to circumvent the planet a whole lot easier by cleverly choosing to stay right here on earth, unless your aim is to circumvent all meaningful interaction with Jupiter, in which case you'd probably do best to leave the solar system altogether.

Or you might be able to circumvent a certain amount of wiseacre silliness on my part by instead proposing to circumnavigate Jupiter in your thought experiment :wink:

Ha! =D>

Just look at the monolith to get an impression of scale



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Even a stopped clock tells the right time twice a day

Here's a thought experiment. We're in low Earth geosynchronous orbit right now. Do we have an appreciation for the Earth's huge size?

Size is relative. Compared to the sun every planet is small. Compared to a melon every planet is huge.

You haven't seen the melons I've seen...... \/

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how come things can move fast in the dark?"
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LOL!
However funny it is when I make these comments someone gives me a "tsk tsk" msg.

So here we go....

[Scorn mode]
tsk tsk [-X
[/Scorn mode]

So thats you told.

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Even a stopped clock tells the correct time twice a day

[quote="Mr. Milton Banana"]Only if they were squashed like Silly Putty. Maybe it's just me, but I was always annoyed by the statements "1300 Earths could fit inside Jupiter" or "1,300,000 Earths could fit inside Sun". Not if they were packed sphere to sphere like oranges in a crate, they would not! I know astronomers mean actual volume, but when laymen hear such things, 99.9% of them get the "packed spheres" image. In such case only about half as many Earths would fit.

[quote="Ilya"]I'm just relaying what I've read. :P

Go after the folks who write the books. They're the ones educating us. :P

More like 2/3, not half, if they're stacked like oranges.

So, which should we use? The laymen's image, or the astonomers's image? If you threw 1300 Earths together, they'd pretty quickly fuse together.

Are these face-centered-cubic-close-packed earths or hexagonal-close-packed earths? Actually the number is closest to 74%. For body-centered-cubic the number is more like 68%.

Maybe we could pack the moon in the interstital spaces between the earths?

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One Earth, One Sky - IYA 2009
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My bad. I should have looked it up. The density for both fcc and hc are the same.

I think Ilya was thinking simple cubic lattice.

Well, for a given altitude the horizon wouldn't curve away as much as it appears to on Earth. So, I think you'd probably feel like you were closer to it. If you had spent a lot of time in LEO then yes I think that sensation of being so much closer would be very impressive and certainly drive home the difference in size. What's more, if you were used to looking at Earth clouds, Jupiter's storms would probably seem pretty scary given that they move so much faster.

You'd have to be careful getting too close though unless you had plenty of fuel. Remember what happened to Shoemaker-Levy 9!

If you haven't played around with the Orbiter spaceflight simulator, you should take a look at it. www.orbitersim.com One of coolest experiences I've ever had in any "game" is traveling to Saturn by way of Jupiter slingshot. When you get within visual range of Jupiter it appears to grow very very slowly for weeks. By the time it completely fills the viewscreen though, it is coming up fast and visibly increasing in size. It is really amazing. You feel like you're going to run right into it! You go from having no visual que as to your speed to feeling like you're freefalling out of an airplane.

I don't know how fast one would need to travel to be in a lower Jovian orbit. I suspect that 130 miles is not a safe distance from the coulds because it might still have enough atmosphere to slow you down and pull you in. But assuming you get as close as is safely possible the orbital velocity must be tremendous. How fast would one transit the over the Great Red Spot?

I think we would notice the parger size by the sheer velocity required for lower orbit. The clouds, while larger structures, would zoom past giving the sense of incredible speed, more so than in LEO.

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J Pax

Orbital velocity in very low Jupiter orbit is in the vicinity of 42 km/sec. That's roughly an order of magnitude faster than LEO, but I don't know if it would seem fast. I suppose that has to do with the scale of the features you can see out the window.

Yes, I was thinking of simple cubic lattice.

Where else but on the BABB would someone point out HOW the spheres are packed!




Wait a minute. Those values are for unit cells, right? Would you have to make a correction for the edge of the sphere?

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I suppose you would but that would take a pretty silly discussion too close to the completely nuts and I'm not going to do it [-(

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At night the stars put on a show for free (Carole King)

One Earth, One Sky - IYA 2009
All moderation in purple

Of course, but you said that the laymen think "if they were packed sphere to sphere like oranges in a crate," which is not simple cubic lattice.

The "edge" of Jupiter is vague anyway, because it is a gas giant. The simple answer is that the 1300 figure is the reasonable one, regardless of what the "laymen" might or might not think. It's not that precise anyway.

Let's also not forget size. Just one of Jupiter's giant thunderstorms could reach 50 miles in height, and can be as much as 2,500 miles wide. A good illustration of what it might be like in the atmosphere of a Jovian planet is the illustration in Carl Sagan's COSMOS, where he talks about possible life forms that could exist in the atmosphere of a Jovian world.

8)