View Full Version : Saturn pics

2002-Feb-01, 12:40 PM
These are impressive: Saturn pics (http://www.eso.org/outreach/press-rel/pr-2002/phot-04-02.html#phot-04a-02), but is that "300 km" dark spot close to the South Pole a typo? If not, where is it exactly?

<font size=-1>[Fixed URL]</font>

<font size=-1>[ This Message was edited by: GrapesOfWrath on 2002-02-01 07:41 ]</font>

2002-Feb-01, 01:29 PM
I can just barely make out the dark spot (I think). It's directly above where I would expect the south pole to be. It's black but at the same time only a little darker than its surroundings - I can only see it in the enlarged photo and even then almost have to use averted vision to see it! If I try to stare at it for more than a couple of seconds, it vanishes.

2002-Feb-01, 04:33 PM
Ah, thanks, ToSeek. I should have enhanced the picture earlier. I just was certain that it wasn't there--Saturn's diameter is around 120,000 km, right? So, a 300 km dot would be 1/400 of its radius--less than one pixel on even this large photo. My guess is it is more like 3000 km:

2002-Feb-01, 06:38 PM
Actually, if you notice out below Saturn is what appears to be a moon. Could it be the moon's shadow? If it was, the moon would be really highly inclined, as it would have to be way below the planet to cast a shadow at that spot. That's a great picture, by the way.


The Bad Astronomer
2002-Feb-01, 07:45 PM
Remember that these pics are infrared, so the colors may not represent what you are used to.

The moon in the image is orbiting in Saturn's equatorial plane; it looks to me like it's on the far side of the planet.

2002-Feb-02, 01:04 AM
Remember that these pics are infrared, so the colors may not represent what you are used to.

Bad Astronomer: Thank you for the information. I had been thinking that the photograph had been artificially colored to show differences in composition more clearly or to separate different areas from each other.

Of course, to show it in infrared, that might force artificial coloration, because (according to my perhaps incorrect information) infrared is not actually able to be viewed in the colors of the visual spectrum? Then again, perhaps these are the visible spectrum colors which result from infrared cameras. Oh, oh, I am getting into deep scientific pseudo doo doo.... I had better stop before I contract foot-in-mouth syndrome.

ljbrs /phpBB/images/smiles/icon_confused.gif /phpBB/images/smiles/icon_rolleyes.gif /phpBB/images/smiles/icon_redface.gif