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PostPosted: Fri Aug 17, 2012 9:21 am 
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David Frydman wrote:
It seems the crater is 154 km across.
The central peak 18,000 ft high and the southern crater wall may be less than 15,000 ft high.
The nearest crater wall is VERY roughly 15km distance, but it landed 2.4 km away from its target and I have no idea of the distance to the mountains shown in the photo.

Regards, David

I assume the view, from smerral's image, shows a part of the Gale crater wall, or rim, and not the general area around Mount Sharp.
Does anyone know, or can anyone work out, the distance to the rim as shown in the image?


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PostPosted: Fri Aug 17, 2012 10:07 am 
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One of the photos had degrees, probably or possibly of azimuth, on it, so if you take the trouble and get a map of where the crater is and the landing zone, or its actual position, you could work it out.
There is also the curvature of Mars's horizon to take into account.
On the Earth the square root of the height in feet x 1.5 gives the approximate distance to the horizon on a flat or sea surface.
So if your eyes are 10ft above the sea the horizon is about 4 miles away.
If you are 10,000 ft up the horizon is about 120 miles away.
Mars is smaller so the curve is more pronounced.
You have to use both the height of the camera and also the height up the crater wall or central mountain to take into account to get line of sight measurements.

So yes, you could work it out, but I am not that interested in working it out and just like the photo.

Regards, David


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PostPosted: Fri Aug 17, 2012 12:10 pm 
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Location: London, UK.
Thanks for the gigapan link, Brian. What an amazing piece of work. I loved the zoom in captions too!

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PostPosted: Sat Aug 18, 2012 2:34 pm 
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Yes we're looking at Gale crater rim and I think you're right David about the 15,000 feet. In the latest shot the mountains look positively :Himalayan! :shock:

Image

Interestingly, this image is white balanced, so we're seeing it in earth light and it makes things easier to see - the original is more murky, as one would expect on Mars. To me there look to be traces of green in the landscape....

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PostPosted: Sat Aug 18, 2012 3:05 pm 
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The hazy view of the distant mountains I suppose is due to dust in the atmosphere.
On the Moon, however distant, I would expect the view to be the same with no atmosphere.

Not a bad place to live, you just need an oasis, and a breathable atmosphere.
Maybe one day we may have a go at making it habitable.
We already have some cars up there.
I suppose with massive plastic domes a mile across one could build cities up there.
Maybe the rocks could produce plastics, and the sunlight the energy needed.

Regards, David


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PostPosted: Thu Aug 23, 2012 9:35 am 
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I'd be reluctant to swop verdant Earth for life on a cinder.

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