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View Full Version : What does Saturn look to the naked eye, orbiting Saturn?



small axe
06-11-2011, 02:43 AM
Okay, let me ask a basic naive (but science fact) question: We all see spaceprobe photos, or Hubble telescope images, showing our outer planets or this or that distant nebula, and the images are bright and the colours rainbow beautiful ...

But those are all computer-enhanced, right?

If an astronaut or cosmonaut or taikonaut orbiting Saturn (let's say) were to look out her porthole ... What would Saturn look like to the naked human eye?

Because the Sun is far distant, obviously.

Does enough sunlight fall on Saturn for it to look illuminated to the human eye? Or is outer space far from the Sun just dark?

http://www.spacetoday.org/images/Saturn/CassiniAtSaturn/SaturnCassini_05_07_04.jpg
Saturn image from Cassini probe ... but ... ?

efkelley
06-11-2011, 04:46 AM
Here you go: http://en.wikipedia.org/wiki/Sunlight

Go down to 'Intensity in the Solar System' for some gauges on relative luminosity.

There's plenty of light to see by at Saturn. Saturn has a pretty decent albedo, thanks to all that ammonia ice in the upper atmosphere.

Here's a 'true color' image: http://en.wikipedia.org/wiki/File:Saturn_%28planet%29_large.jpg though I don't know if the luminosity has been modified.

Anyway, I hope that helps.

thewakingself
06-12-2011, 12:46 AM
There's a newish short film pieced together from Cassini's images, located here: http://news.discovery.com/space/when-cassini-met-nine-inch-nails-110602.html Primary video here: http://vimeo.com/24410924

It's in black and white, and a little disorienting, but it shows some of the brightness and gives a better sense of three-dimensionality, imo.

Also, as I watched it, I keep expecting my phone to ring, and someone to say: "Seven days." :D

blacbird
06-12-2011, 12:53 AM
Does enough sunlight fall on Saturn for it to look illuminated to the human eye?


Of course it does. We can see the planet easily with the naked eye here on Earth.

small axe
06-12-2011, 01:29 AM
Thank you for the responses! Those videos are stunning ... and


Of course it does. We can see the planet easily with the naked eye here on Earth.

... good gosh. The question crossed my mind, I pondered it and the obvious answer didn't even occur to me! We can see the reflected light even here from Earth. Duh.

But I'm glad I asked, because I luv the videoes AND the list of light falling on outer planets! So thanks to you all!

Anaximander
06-12-2011, 05:22 PM
My grandad has a fantastic Newtonian reflecting telescope, and he lives in the country away from light pollution, so I've had a look myself. That Wikipedia image that efkelley linked is pretty accurate in terms of colour - when I looked the rings were a little darker, but that's partly because of the angle; from Earth, they're pretty side-on most of the time, so they're harder to see.

I've also seen Jupiter closely enough to make out the stripes (yes, it really is pretty red) and four moons.

blacbird
06-13-2011, 02:16 AM
when I looked the rings were a little darker, but that's partly because of the angle; from Earth, they're pretty side-on most of the time, so they're harder to see.

Not really, though they are right now through the happenstance of Saturn having earlier this year passed through its equinox, when the rings are edge-on to the sun, and essentially become invisible. As I recall, Saturn's orbital period is 27 earth years, so it hits equinox every 13 or 14 years. In between those times, the rings appear at a significant angle both to the sun and to the POV of earth, and are quite visible. In fact, Galileo discovered them at such a time, with his crude early telescope, thought they were extensions of the planet, and compared them to ears.

Here are a number of excellent photos of Saturn, including an infrared one from the Keck telescope in Hawaii, which shows something near the maximum angle of Saturn's rings as visible from Earth.

http://www.optcorp.com/edu/articleDetailEDU.aspx?aid=464