APOD 14th December 2005 Shadows

Comments and questions about the APOD on the main view screen.
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APOD 14th December 2005 Shadows

Post by JohnD » Wed Dec 14, 2005 7:28 am

The history of criticism and cynicism about shadows in space exploration pics is shameful - eg Apollo - and I enjoy this simulated pic of a Mars Rover on its ground, but ......

The shadow of the Rover is shown as diffuse. Shadows in real pics are sharp. Is this supposed to be during a dust storm?

I know, picky-picky, it's only a simulated pic etc.

What do you think?


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Post by l3p3r » Wed Dec 14, 2005 8:50 am

well, for the purposes of showing the rover to scale with the landscape, yes that is a little picky :p

http://www.jpl.nasa.gov/images/mer/2005 ... 23-540.gif

I see what you mean though.
I expect the main reason is that diffuse shadows are easier to draw onto the existing image. :)

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Post by Empeda2 » Wed Dec 14, 2005 9:26 am

Hmmm.. difficult to say - Mars has quite a dusty atmosphere, and looking at the 'photo' it looks as though it's being simulated late evening/early morning - more dust to go through - less sharper shadow (the pictures in the link above look like the sun's almost directly overhead...).

Anyway, still 8)
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Post by S. Bilderback » Wed Dec 14, 2005 12:27 pm

Midday on Mars is about as bright as approaching twilight on Earth.
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Post by Empeda2 » Wed Dec 14, 2005 12:47 pm

I was looking more at the angle of the shadow - but that's something I forgot of course....
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rover soft shadow

Post by ta152h0 » Thu Dec 15, 2005 3:32 am

The angle of the shadows indicate a low Sun angle and there is not enough atmosphere under the electric panels to diffuse the light. I wish I had the ability to draw that good............
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