Comments on: The ups and downs of Saturn pictures

By: tracer

tracer — Wed, 13 Jun 2012 20:54:39 +0000

I have the same problem whenever I look at a photo of craters.

Most of the time, my mind renders the picture in my head as circular dome-shaped bumps sticking OUT of the planet/moon, not circular bowl-shaped depressions sticking in.

By: Joseph G

Joseph G — Tue, 12 Jun 2012 09:32:58 +0000

It’s a lovely image to be sure, and my very first thought was; I wonder if Epimetheus is closer to us than the rings, or farther away? If we’re looking down on the rings, from the north, then Epimetheus is closer to us. But if we’re looking up from underneath the rings, Epimetheus is on the other side of the rings.

At first I thought that that might not necessarily follow. After all, what if Epimetheus’ orbit were inclined to the plane of the rings? Depending on the point in its orbit when the image is captured, it might then appear “up” or “down” regardless of its distance.
Of course, then I wiki-ed Epimetheus and found that it has an extremely low inclination. So I learned something today

By: alfaniner

alfaniner — Tue, 12 Jun 2012 05:14:43 +0000

I find that if I think of it as “Death Star approaching Yavin” it’s a lot easier.

By: kevbo

kevbo — Tue, 12 Jun 2012 04:30:03 +0000

This is classic Bad Astronomy (as in ‘Good” Astronomy). Nice post!

By: Richard Drumm The Astronomy Bum

Richard Drumm The Astronomy Bum — Tue, 12 Jun 2012 04:04:13 +0000

What I noticed was the absence of the Cassini division. I thought it was because the image was in UV light or something, but it was the unfamiliar-from-Earth backlighting! Good one!

By: CR

CR — Tue, 12 Jun 2012 00:25:08 +0000

Woo-hoo!
I got it right (looking up, not down).

By: John S.

John S. — Mon, 11 Jun 2012 23:03:35 +0000

I guessed we were beneath the ring plane based on two things: The F Ring seems thinner where it crosses the photo lower down; and the lower edge of the rings is less bright than the upper edge, which to my eyes says distance. Neither thing may be a reliable indicator though– I had a 50% chance of being right with just a guess.

By: Chris A.

Chris A. — Mon, 11 Jun 2012 20:14:32 +0000

@Carey (#1):
“Chronos” != “Cronus” Two different mythical beings; only the latter is a cognomen for Saturn.

By: Carey

Carey — Mon, 11 Jun 2012 19:54:07 +0000

To be honest, it doesn’t look “right” to me if I try to think of it as looking down on the rings (with the rings on the bottom closer to me, and the top farther away).

In fact, this is how I initially interpreted it, but that made the outermost grouping look warped out of plane with the rest of the rings, at the top part of the picture. I thought there was something strange going on, maybe with shadows on Saturn’s surface or something.

But when I told my brain to think about looking up at the rings, with the top rings closest to me, and the bottom rings farther away, it looked much better. You can see that there’s a much bigger gap on the top than on the bottom, between the outer group and the next, fainter, group in. Naturally, that gap would be bigger if it was closer to you, so the top must be closer.

In fact, there are several analogous features that are bigger on top than they are at the bottom. And you don’t even have to encronosenate the picture to see them! Shouldn’t it be “enchronosenate”? Or is there another spelling of Chronos I’m unfamiliar with?