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Cassini Beams Back First Images from New Orbit

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Re: Cassini Beams Back First Images from New Orbit

#31
post #11
post #10

Earlier quoted context omitted.

Well said. But, you know, with all its moons and rings, Saturn is way cool-looking than any other planet in our Solar System. That's why they called it that way, I guess.

Perhaps from a huge distance, but I think we win the title on any other scale. Earth is pretty stunning.

without having travelled to other planets its pretty premature to have any opinion.

Re: Cassini Beams Back First Images from New Orbit

#32

Every time I see photos of the big gas planets like this, I imagine earth orbiting the gas giant and feel very, very small and get what feels like mild vertigo from the overwhelming scale. This is truly wonderful

If you think Saturn's big: https://www.youtube.com/watch?v=GoW8Tf7hTGA (though this sort of thing is far more impressive when seen in VR) But even better than that, for me, is going somewhere with very little light pollution at night and simply looking up at the Milky Way. Nothing makes me feel smaller and more in awe.

My favorite segment of that is the universe's "web" of galaxies. There's something pleasing about the way they've all arranged themselves. Much more pleasing than the clustering of stars in a galaxy.

Re: Cassini Beams Back First Images from New Orbit

#33

Every time I see photos of the big gas planets like this, I imagine earth orbiting the gas giant and feel very, very small and get what feels like mild vertigo from the overwhelming scale. This is truly wonderful

It always reminds me about Total Perspective Vortex.

Re: Cassini Beams Back First Images from New Orbit

#35

For those who are also wondering about the briefly mentioned hexagon-shaped jet stream: One hypothesis, developed at Oxford University, is that the hexagon forms where there is a steep latitudinal gradient in the speed of the atmospheric winds in Saturn's atmosphere. Similar regular shapes were created in the laboratory when a circular tank of liquid was rotated at different speeds at its centre and periphery. The mo…

I like this work and the presentation by Tianlu Yuan (2013) about how our knowledge about the subject progressed -- the first photos were made by Voyager (1981-82):

http://www-hep.colorado.edu/~tianlu/public/saturnHex_paper.p...

http://www-hep.colorado.edu/~tianlu/public/saturnHex_present...

"In the 1980s images of Saturn taken by Voyager led to Godfrey's surprising discovery of a hexagonal structure on the planet's north pole [9]. Now, over three decades later, Saturn's north polar hexagon remains, superficially unchanged and not entirely understood. Voyager's iconic images proved a challenge to explain theoretically, but with additional data from ground based observations and the HST in the early 90s, and images from the Cassini mission more recently, our knowledge of many physical parameters forming the hexagon has increased. Along with observation, laboratory experiments and numerical simulations have helped foster greater understanding of the possible causes of the jet's six-sided shape."

The more recent pictures (2016) are also interesting, as the color has changed(!):

http://www.forbes.com/sites/startswithabang/2016/10/31/satur...

And for completeness, the comics from 2010:

http://www.smbc-comics.com/comic/2010-07-06

Re: Cassini Beams Back First Images from New Orbit

#36
post #10

> remind you that we’ve lived a bold and daring adventure around the solar system’s most magnificent planet Other than the one we're standing on, you mean.

Well said. But, you know, with all its moons and rings, Saturn is way cool-looking than any other planet in our Solar System. That's why they called it that way, I guess.

It's hard not to find Saturn intriguing, the rings, the colors, the moons. It's the first time I saw something through a telescope that was awe inspiring. It almost seemed cartoonish with it's vibrancy and sharp edges. It's enough to make anyone want to take up astronomy.

Re: Cassini Beams Back First Images from New Orbit

#37

Every time I see photos of the big gas planets like this, I imagine earth orbiting the gas giant and feel very, very small and get what feels like mild vertigo from the overwhelming scale. This is truly wonderful

If you think Saturn's big: https://www.youtube.com/watch?v=GoW8Tf7hTGA (though this sort of thing is far more impressive when seen in VR) But even better than that, for me, is going somewhere with very little light pollution at night and simply looking up at the Milky Way. Nothing makes me feel smaller and more in awe.

I like how, when showing the increasing star size, they show a little piece of the next, bigger, star just to let you know "hey, we're not done yet!". There are big things out there, people.

Re: Cassini Beams Back First Images from New Orbit

#38
post #36
post #10

Earlier quoted context omitted.

Well said. But, you know, with all its moons and rings, Saturn is way cool-looking than any other planet in our Solar System. That's why they called it that way, I guess.

It's hard not to find Saturn intriguing, the rings, the colors, the moons. It's the first time I saw something through a telescope that was awe inspiring. It almost seemed cartoonish with it's vibrancy and sharp edges. It's enough to make anyone want to take up astronomy.

yeah. I also found seeing the moons of jupiter around jupiter pretty amazing. can kind of see how galileo came to the conclusions he did.

Re: Cassini Beams Back First Images from New Orbit

#39
post #26

the one concern i have - isn't the spacecraft fueled by a small plutonium reactor? there's no risk of it going Big-B Boom?

In short, no, there is no risk. When we say a spacecraft is nuclear-powered, we're not actually referring to a reactor (with rare exceptions[1]), but instead to something called a Radioisotope Thermal Generator[2], or RTG for short. Basically, an RTG contains radioactive material (material that undergoes constant, passive radioactive decay). This constant decay produces heat, which is then used to generate electricit…

The risk comes at launch; if there is an explosion, the plutonium core can be scattered over a wide area.

Re: Cassini Beams Back First Images from New Orbit

#40

For those who are also wondering about the briefly mentioned hexagon-shaped jet stream: One hypothesis, developed at Oxford University, is that the hexagon forms where there is a steep latitudinal gradient in the speed of the atmospheric winds in Saturn's atmosphere. Similar regular shapes were created in the laboratory when a circular tank of liquid was rotated at different speeds at its centre and periphery. The mo…

> Saturn's south pole does not have a hexagon, according to Hubble observations; however, it does have a vortex, and there is also a vortex inside the northern hexagon. (o)

could the fact that there is only one hexagon imply a consequence of the 'hairy ball theorem'?(i)

(o) https://en.wikipedia.org/wiki/Saturn's_hexagon

(i) https://en.wikipedia.org/wiki/Hairy_ball_theorem

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