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Jupiter’s North Pole Unlike Anything Encountered in Solar System

nasa.gov

41–50 of 91 posts

Re: Jupiter’s North Pole Unlike Anything Encountered in Solar System

#41
post #19

Earlier quoted context omitted.

Yes. What's the point you're trying to make? (genuine question)

To express skepticism about >The largest planet in our solar system is truly unique.

It's unique within our solar system, the only one we have details about. I think it's fair to state that as being unique. The implication (that we don't know about other solar systems) doesn't need to be stated, at least to me.

Re: Jupiter’s North Pole Unlike Anything Encountered in Solar System

#42
post #6

Absolutely breathtaking. Interesting that they phrase the headline almost as if to imply uniqueness. My impression was that Saturn's hexagon was the unique situation (occurring, hypothetically, only under very specific conditions). Is it expected then that Uranus and Neptune's poles will look different still?

Uranus has an axial tilt of around 90°, so it is undoubtedly completely wacky. I have no idea what Neptune's looks like.

Re: Jupiter’s North Pole Unlike Anything Encountered in Solar System

#43

"The download of six megabytes of data collected during the six-hour transit, from above Jupiter’s north pole to below its south pole, took one-and-a-half days." ...surely that's a typo and they mean gigabytes?

Google Fiber really needs to step up the interplanetary deployment!

Imagine you need to ping google.com from mars. The round trip would be at least 40 minutes. Put a whole new meaning into the word lag.

Seriously though, the current TCP/IP protocol is not designed to deal with that kind of distance.

Re: Jupiter’s North Pole Unlike Anything Encountered in Solar System

#44
> “Saturn has a hexagon at the north pole,” said Bolton. “There is nothing on Jupiter that anywhere near resembles that. The largest planet in our solar system is truly unique. We have 36 more flybys to study just how unique it really is.”

Eh? Jupiter is 'truly unique' because it doesn't have an extremely puzzling feature that only one other planet is known to have?

Re: Jupiter’s North Pole Unlike Anything Encountered in Solar System

#45
post #22

Earlier quoted context omitted.

According to Wikipedia, the world's average energy consumption is 12.3Tw. Given that the Earth is gets 1366 W/m² of solar power at 149,597,870km, this means Mercury gets 9190 W/m² at 57,910,000km. Plugging these together, this tells us that a 12.3Tw solar array of 100% efficiency in Mercury's orbit would have a surface area of 1338 km². Realistically, you'd at least double that, to produce the same power, as solar pa…

Brilliant, thanks. So how long before we start putting solar panels in close, direct orbit around the Sun?

About the same time we reach Type II Civilization status and can build a Dyson Sphere!

https://en.wikipedia.org/wiki/Kardashev_scale#Type.C2.A0II_c...

Re: Jupiter’s North Pole Unlike Anything Encountered in Solar System

#46
Ignoring all the fascinating stuff about Jupiter, let me point out this gem: The download of six megabytes of data [...] took one-and-a-half days

I sometimes like to scare kids by telling them about the time when I surfed the Internet with 14.4 kbit modem, but even that looks incredibly fast compared to the speed of interplanetary data transmission (back then, 6 MiB would have taken me about 2-2.5 hours).

(NB that I am not complaining or anything, just pointing out that this is many orders of magnitudes slower than anything one would normally consider a "slow" connection.)

Re: Jupiter’s North Pole Unlike Anything Encountered in Solar System

#47
post #4

Earlier quoted context omitted.

The solar panels that Juno has produce only 500 watts of power. You would need a lot more then that to be sending gigabytes of data in any meaningful timeframe. So yes it really is just six megabytes of data taking 30h+ to download. Btw the panels would produce 14kW at earth orbit but suns power goes down quite fast as you move away from it. Also the farthest from the Sun we've ever used solar panels. Traditionally m…

Transmission is one thing, but collection is another: did they really only collect 6 megabytes of data over the course of a 6 hour flyby? Off topic, ish: does anyone know how large a solar panel array would have to be to supply all of our current energy use, if the array orbited the Sun at the same distance Mercury does?

Almost all of the instruments on Juno are non-visual. The camera was included mostly for PR purposes. 6MB is pretty good for one-dimensional data streams.

Re: Jupiter’s North Pole Unlike Anything Encountered in Solar System

#48
post #5

“Saturn has a hexagon at the north pole,” said Bolton. “There is nothing on Jupiter that anywhere near resembles that. The largest planet in our solar system is truly unique. We have 36 more flybys to study just how unique it really is.” This is the first I've heard of Saturn's hexagon, very interesting: http://www.space.com/30608-mysterious-saturn-hexagon-explain...

Some threads I read on another site described it as perturbations of a periodic wave moving around the pole in a circle.. modeled something like this:

http://www.wolframalpha.com/input/?i=plot+x%5E2+%2B+y%5E2+%3...) or http://www.wolframalpha.com/input/?i=r+%3D+1+%2B+cos(6*theta...

Re: Jupiter’s North Pole Unlike Anything Encountered in Solar System

#49
post #40

I wonder if the clouds don't separate into bands as much at those latitudes because the velocity (due to the planet's rotation) is lower closer to the poles.

The Coriolis force is strongest at the poles and weakest at the equator, so I presume there would be more rotation and thus less banding near the poles due to this effect.

The origin of the banding is supposedly similar to the banding on Earth, which has three broad 'bands' driven by Hadley cells (polar, mid-lattitude, tropical), driven by convective heating moving energy away from the equator towards the poles, except presumably Jupiter has much more energy and therefore more convection and more bands.

I only have a very crude understanding of atmospheric forces, though, so paging someone who knows better.

Re: Jupiter’s North Pole Unlike Anything Encountered in Solar System

#50
post #46

Ignoring all the fascinating stuff about Jupiter, let me point out this gem: The download of six megabytes of data [...] took one-and-a-half days I sometimes like to scare kids by telling them about the time when I surfed the Internet with 14.4 kbit modem, but even that looks incredibly fast compared to the speed of interplanetary data transmission (back then, 6 MiB would have taken me about 2-2.5 hours). (NB that I…

It's also fascinating to think about how TCP is ineffective at that distance.

https://en.wikipedia.org/wiki/Interplanetary_Internet is a good starting point to learn more.

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