Iapetus in color again

[mmcirvin]

This is an attempt at a natural-color picture, from RGB filters:



There's just a slight brownish tint there. You can see the end of the mysterious equatorial mountain range coming in over the horizon on the left. It looks like it runs out not far from the edge of the biggest crater.

Comments

[muffyjo]

Not seein' brown. I see contrast, just not brown. Wicked cool! btw, do you happen to know of any good astronomy sites for kids? I have a friend who is going to buy a telescope for his daughter who is about 12 and he was asking me (why me?) so I thought I would see if you knew of any (because you know all about these things, right?).

[mmcirvin.livejournal.com]

Most of the moons of Saturn, including Iapetus, have very little color to them, and most of the pictures of Iapetus where the dark region looks chocolatey (including the color ones I posted in late 2004) are actually false-color images done with IR/green/UV frames. In true color it's just slightly off neutral gray.

But monitor characteristics count for a lot too. My monitor tends to make things look browner than they are, so I can often not tell whether a picture looks completely gray to other people.

[muffyjo]

It bears a remarkable resemblance to the Death Star...

[mmcirvin.livejournal.com]

The Saturn system is full of Death Stars because several of its moons have giant craters that dominate their geography; Mimas and Tethys are the famous cases, since the Voyagers saw their giant craters way back when. But Iapetus's equatorial ridge gives it an additional artificial look, to the extent that it's become another spur for Richard Hoagland's craziness.

[muffyjo]

Sure, and the shadow in its particular configuration makes it look like part of it is missing as well.

Did you have any ideas on kids' sites?

[mmcirvin.livejournal.com]

I don't know much about kids' sites, but for a 12-year-old who's interested in astronomy, I'd say that a lot of the "adult interested layperson" material would be appropriate and comprehensible. The Planetary Society (http://www.planetary.org/home/) just redesigned their site and there's a tremendous amount of good stuff there. NASA's Astronomy PIcture of the Day (http://antwrp.gsfc.nasa.gov/apod/astropix.html) is usually incredibly cool and the captions have links to associated material; it's a good place to start exploring. The Jet Propulsion Laboratory home page (http://www.jpl.nasa.gov/) is good for keeping up with planetary exploration, and the Cassini home page (http://saturn.jpl.nasa.gov/home/index.cfm) is frequently updated with interesting things.

Most of the government and nonprofit sites have "for kids" sections too, of varying quality.

[mmcirvin.livejournal.com]

Oh, yeah, also, people who talk about exploration of the solar system sometimes forget the biggest piece of all, the Sun. Observing the Sun safely by yourself takes special precautions (astronomers yell about how you'll put your eye out so much that it becomes comical, but it's true, you really can put your eye out, especially with a telescope; she'll want to read up on proper procedures).

But fortunately, two of the spacecraft that study the Sun full-time have awesome web sites: I've always been partial to the TRACE image of the day (http://trace.lmsal.com/POD/TRACEpod.html) (a bit chaotic, but full of gorgeous pictures), and also SOHO's raw image feed (http://sohowww.nascom.nasa.gov/).