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OSIRIS-REX mission to 1999 RQ36 (Bennu), New Frontiers Mission to Launch in 2016
mcaplinger
post Sep 27 2017, 06:54 AM
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QUOTE (Hungry4info @ Sep 26 2017, 08:39 PM) *
Are these images actually circular rather than rectangular?

Not sure what you mean by this.
QUOTE
And can we expect those drop outs (?) as the "norm"?

Did you actually read the caption?

"The dark vertical streaks at the top of the image are caused by short exposure times (less than three milliseconds). Short exposure times are required for imaging an object as bright as Earth, but are not anticipated for an object as dark as the asteroid Bennu, which the camera was designed to image."

That said, I'm not sure why short exposure times would cause streaking like that -- maybe blooming from the horizontal register?



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Disclaimer: This post is based on public information only. Any opinions are my own.
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ugordan
post Sep 27 2017, 10:39 AM
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QUOTE (mcaplinger @ Sep 27 2017, 08:54 AM) *
Not sure what you mean by this.

I'd guess the jagged limb Earth displays indicating this is an orthographic projection (due to noticeable s/c motion or whatever) instead of a straight-up RGB composite.


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volcanopele
post Sep 27 2017, 01:53 PM
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I thought they were truncated lines due to undercompression. We saw that with Galileo and Cassini, though on Cassini, we had truncated lines every other line to allow for interpolation.


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Hungry4info
post Sep 27 2017, 03:36 PM
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I thought it might have been a reprojection as well but you can see some of the image goes above the limb of the planet on the upper-left side. I'm at work right now so I don't have the ability to circle it in an image, I'm afraid. The whole picture looks like it was taken through a circular window that's slightly misaligned/off-centre with Earth.


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fredk
post Sep 27 2017, 04:31 PM
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I guess this is what Hungry's referring to - this is a gamma-tweaked crop:
Attached Image

You can see that it looks like the image was masked to black outside a circle. It's noticable at the top of the frame because the mask follows the true edge of the Earth which is in shadow there (the phase is slightly gibbous) rather than the visible limb.

Presumably this was done to get rid of some noise in the black regions. Hopefully they didn't mask out too much of the bright limb, but the bright limb looks too sharp (ie it looks aliased) rather than PSF-y as you'd expect...
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Paolo
post Sep 28 2017, 06:26 PM
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more pics. including the Moon
https://www.nasa.gov/feature/goddard/2017/o...th-and-the-moon
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Paolo
post Oct 11 2017, 05:34 AM
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Earth anf Moon in color
http://www.asteroidmission.org/?latest-new...arth-moon-color
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