Comments on: Peek-a-moon!

By: quasidog

quasidog — Sat, 20 Dec 2008 22:07:48 +0000

Unreal. The detail in Ganymede (not that I was aware it was) was the first thing that I noticed. An amazing shot.

By: Autumn

Autumn — Sat, 20 Dec 2008 06:39:41 +0000

Thanks, Phil. I guess I was just making basic mistakes in trying to scale objects according to my preconceptions. After so many years of math, I still overestimate the relative diameters of spheres with regard to their volume.

By: Peek-a-movie! | Bad Astronomy | Discover Magazine

Peek-a-movie! | Bad Astronomy | Discover Magazine — Fri, 19 Dec 2008 17:23:01 +0000

[...] was just informed by Twitterer karabaic that the picture of Ganymede going behind Jupiter that I posted yesterday also comes with a very cool [...]

By: Phil Plait

Phil Plait — Fri, 19 Dec 2008 17:09:46 +0000

Autumn, swan: the GRS changes its size over time a bit. A quick look at wikipedia has a comparison of it and the Earth that makes the scale of this image look about right: http://en.wikipedia.org/wiki/Great_Red_Spot#Great_Red_Spot

By: swan

swan — Fri, 19 Dec 2008 17:01:07 +0000

Like Autumn, I’m a bit befuddled by the apparent size of Ganymede compared to Jupiter. I even scaled this to a stock picture to make sure this wasn’t the Less Spot of Jupiter.

By: My-Name-is-Kenneth

My-Name-is-Kenneth — Fri, 19 Dec 2008 16:04:55 +0000

What’s that growing black spot in Jupiter’s atmosphere? Is the planet losing its chemical stain?

By: Autumn

Autumn — Fri, 19 Dec 2008 05:56:30 +0000

Has the Great Red Spot shrunk recently? I thought that the GRS was about two or three Earth diameters across, but if Ganymede is behind Jupiter in this image, Ganymede appears to me to be nearly Earth-sized. I am just remembering stuff off the top of my head, so I’m probably wrong about this, but I assumed that the moon was in front of Jupiter when I initially looked at the picture. Seems too big.