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Russ
2001-Nov-15, 12:39 AM
This is a super nit pick but I just couldn't resist.

In the December issue of Astronomy Magazine on pages 80-81 is the start of an article on the paintings of "Space Artist" Chesley Bonestell.

The painting duplicated on these pages is titled "saturn as Seen from Titan". Saturn itself is in a very early phase and is just a sliver in the ring system. Most of the planet is in shadow. There is even a shadow of the rings on the sliver of the planet in Sunlight. The bad astronomy in this case is that none of the ring system is in shadow. You can see it all the way around Saturn.

I'll grant that Mr. Bonestell painted this in 1944 before anyone had actually seen Saturn up this close. But even I can see the shadow on the rings through my 10" amature scope, so I assume astronomers of the time knew that it would be there. According to the article Bonestall was very in to astronomy and, again I assume, would be aware that there would be a shadow on the rings from this angle.

Otherwise, I really like his work. There is a very impressive Moonscape and another angle on Saturn that I like. Well worth the price of the magazine to have a look.

NottyImp
2001-Nov-15, 09:21 AM
Great name, though, Chesley Bonestell. Nearly as good as Flip Spiceland...

David Hall
2001-Nov-15, 11:28 AM
Speaking of which, is there ever a time when the rings are completely out of shadow? It doesn't look like the angle of tilt is quite enough for that, but looking at this wonderful photo (fittingly enough posted on my birthday), it looks like it comes darned close.

http://antwrp.gsfc.nasa.gov/apod/ap010702.html

I think it's unlikely, but you never know. I've been wrong before. /phpBB/images/smiles/icon_smile.gif

amstrad
2001-Nov-15, 12:45 PM
Is this the picture you are refering to:

Saturn as Seen from Titan (http://www.novaspace.com/LTD/BONESTELL/Titan.html)

in which case, I can see a shadow on the rings, in fact it looks like the right place - 180 degrees from the direction of the sun.

GrapesOfWrath
2001-Nov-15, 12:57 PM
amstrad

I see a shadow also, but it's a little subtle. But I'm wondering--the sun side is shifted towards us on the right of Saturn, so shouldn't the shadow side be shifted away from us on the left? It looks more like it is also shifted towards us.

OTOH, the geometries of long distance or telephoto images are often counter-intuitive.

ToSeek
2001-Nov-15, 01:53 PM
On 2001-11-15 07:57, GrapesOfWrath wrote:
amstrad

I see a shadow also, but it's a little subtle. But I'm wondering--the sun side is shifted towards us on the right of Saturn, so shouldn't the shadow side be shifted away from us on the left? It looks more like it is also shifted towards us.

OTOH, the geometries of long distance or telephoto images are often counter-intuitive.


I don't think so. Based on the phase of Saturn, it looks to me as if the sun is just barely out of view to the right of the picture. To borrow lunar terminology, it's almost a "new" Saturn, which would mean the sun and Saturn are in roughly the same direction. So I think the shadow is consistent.

If I understand you rightly, a shadow pointing away from us would be consistent with a Saturn that's more than half-lit, with the sun behind us in the picture.

GrapesOfWrath
2001-Nov-15, 02:10 PM
<a name="doh">D'oh. Of course, you're right. If Saturn were "all shadow", we'd see the sun behind it, in the picture, and the shadow on the rings would be directly towards us. If we moved to the right, we'd see some of the limb, and the shadow would be shifted left.

<font color="#FCFCFC" size=-1>[Set name field]

<font size=-1>[ This Message was edited by: GrapesOfWrath on 2002-03-25 08:03 ]</font>

ToSeek
2001-Nov-15, 03:23 PM
On 2001-11-15 09:10, GrapesOfWrath wrote:
D'oh. Of course, you're right. If Saturn were "all shadow", we'd see the sun behind it, in the picture, and the shadow on the rings would be directly towards us. If we moved to the right, we'd see some of the limb, and the shadow would be shifted left.


Exactemundo.

Silas
2001-Nov-15, 04:56 PM
...And if you magnify the image, you can see the miniature buildings and footprints and...

(yes, sir, shutting up...)

Silas

Valiant Dancer
2001-Nov-15, 05:01 PM
On 2001-11-15 11:56, Silas wrote:
...And if you magnify the image, you can see the miniature buildings and footprints and...

(yes, sir, shutting up...)

Silas



Shuttles! Shuttles!

(ok. gonna try to behave now.)

Russ
2001-Nov-15, 09:19 PM
On 2001-11-15 07:45, amstrad wrote:
Is this the picture you are refering to:


It looks very similar but not exactly the same. The one in Astronomy Magazine is much closer to the rock cliff and you (I) can see no shadow on the rings.

This is an interesting difference. I wonder whether he painted two or if the Astronomy version was doctored to fit??? Anyone know what's up?