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Fast and Curious

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Originally posted by Soothfast
At http://www.jpl.nasa.gov/spaceimages/details.php?id=PIA00825 you can see Hubble images of Pluto, and they're said to be at a resolution of "100 miles per pixel". Since Pluto is about 1400 miles in diameter, this means the images consist of a bit over 150 pixels (just counting Pluto's surface and not the blackness of space surrounding it).

EDIT: I gu ...[text shortened]... A simple program can take one "red" pixel and break it into a grid of 16 smaller "red" pixels.
I assume you mean 150 square pixels, say 12X12 pixels or 13 X 13 or so. That works out to about 0.005 arc seconds of resolution, or cutting a circle in 250,000,000 parts or so. I thought Hubble was only good for 0.05 arc seconds. Pluto is about 2370 km across and the distance is about 7.5 E9 km which is about 47E9 km circumference. So to get 160 km res at that distance is splitting the circle in almost 300 million parts, If so, my number for the res is off by a factor of 10.

Soothfast
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Planet Rain

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Originally posted by sonhouse
I assume you mean 150 square pixels, say 12X12 pixels or 13 X 13 or so. That works out to about 0.005 arc seconds of resolution, or cutting a circle in 250,000,000 parts or so. I thought Hubble was only good for 0.05 arc seconds. Pluto is about 2370 km across and the distance is about 7.5 E9 km which is about 47E9 km circumference. So to get 160 km res at t ...[text shortened]... g the circle in almost 300 million parts, If so, my number for the res is off by a factor of 10.
Well, look at the link. Anything I might tell you would come from there.

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Originally posted by Soothfast
Well, look at the link. Anything I might tell you would come from there.
If they are right, say a line across the equator of Pluto or whatever you want to call the line more or less parallel to Earth's equator (I think Pluto is tilted pretty drastically) anyway, a line across Pluto that Hubble splits into about 15 or so pixels, if correct, and the data seems to support that, I think what that means is heavy analysis of what pixels they do see, maybe it only takes 3 pixels to interpolate to 15.

googlefudge

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Given that I posted a simple equation that gives you the maximum angular resolution
possible for a telescope of a given diameter... Why are you guys messing around with
fudge factors based on Hubble which may very well not be designed for maximum
resolution for it's diameter???

Just use the equation I gave you, it's much simpler, and has no fudge factors in it.

Soothfast
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Originally posted by googlefudge
Given that I posted a simple equation that gives you the maximum angular resolution
possible for a telescope of a given diameter... Why are you guys messing around with
fudge factors based on Hubble which may very well not be designed for maximum
resolution for it's diameter???

Just use the equation I gave you, it's much simpler, and has no fudge factors in it.
I think the notion of "pixel" should never have been injected into the analysis. Let's see, who first brought up pixels in this thread...? Hmm...

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Originally posted by Soothfast
I think the notion of "pixel" should never have been injected into the analysis. Let's see, who first brought up pixels in this thread...? Hmm...
What's wrong with using pixels?

We are talking about breaking an image down into it's smallest resolvable blocks.

Pixels fit perfectly and intuitively.

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