APOD: Approaching Pluto (2015 May 27)

[ta152h0]

thank you for the answer.

[montylc2001]

Chris Peterson, perhaps. Unless Pluto suffered a major collision which broke it up and created it's 5 moons. Would be interesting to see that Pluto HAS been broken up and it's moons can be fitted back to the main body like a jigsaw puzzle. We shall see.

[montylc2001]

Chris Peterson, perhaps. But it would be interesting to see that Pluto has been broken up by impact and it's 5 moons can be refitted to the main body like a jigsaw puzzle. We shall see.

[Simen1]

The size threshold at which a body becomes round is highly uncertain, perhaps 200-1200 km. Ref http://mel.ess.ucla.edu/jlm/epo/planet/AAS09JLM.pdf p.12

https://en.wikipedia.org/wiki/List_of_S ... ts_by_size

Pluto is almost 1200 km in diameter and thus at the high end of sizes that might not be round. Due to the high uncertainty i wouldn't rule away non-roundness completely. Defining roundness might be hard due to increasing mountain hights (in % of diameter) when the size gets smaller. I think there is a reasonable chance Pluto might have very large craters and hight featues.

[geckzilla]

The apparent flat sides of Pluto in the new images will go away once we receive even higher resolution images. I actually have no idea how they put the images together to get this much detail out of them. If you check out the raw data, Pluto fits within an 11x11 pixel square. That's barely enough to form a smooth, round circle. How someone manages to get all the detail in the press release images is not something I understand. It frustrates me that I don't know how.

[Simen1]

They probably use lots of techniques. First removing all the known disturbances like internal reflections inside LORRI and compensating for vignetting. Deconvolution are "wrapping" optical distortions backwards via advanced knowledge of how the distortions are made and computer algorithms. Then several images may be superimposed to a superresolution image. That means letting pixel grids from several images overlap to reveal features smaler then one pixel. This is not stright forward overlapping since Pluto rotates between images. Knowledge about the rotation and assuming a spheric shape is input to the computer algorithms as well as the deconvolved images. Contrast enhancement is probably used to. And probably techniques i don't know about.

https://en.wikipedia.org/wiki/Superresolution
http://www.oxforddictionaries.com/us/de ... onvolution

Actually hobby astronomers have some nice software tools to superresolve and reducing atmospheric disturbances "lycky imaging".
https://en.wikipedia.org/wiki/Lucky_imaging
http://www.astronomie.be/registax/

[neufer]

They probably use lots of techniques. First removing all the known disturbances like internal reflections inside LORRI and compensating for vignetting. Deconvolution are "wrapping" optical distortions backwards via advanced knowledge of how the distortions are made and computer algorithms. Then several images may be superimposed to a superresolution image. That means letting pixel grids from several images overlap to reveal features smaler then one pixel. This is not stright forward overlapping since Pluto rotates between images. Knowledge about the rotation and assuming a spheric shape is input to the computer algorithms as well as the deconvolved images. Contrast enhancement is probably used to. And probably techniques i don't know about.

All that good stuff.

They probably assume a flat spherical surface with an arbitrary distribution of albedo variation (from 0 to 1).

The blandest albedo map (i.e., the one with the minimum of total variation)
that agrees with the observations is what gets shown.

[geckzilla]

I've read about that (that Wikipedia article specifically, in fact) but reading and knowing how are still two different things.

[ta152h0]

went to a seldom travelled road and drove at a specific speed noting the time it took to get to a specific tree. Went back, closed my eyes and drove the same way with my camera pointed out the window counting off the time and snapped pictures and the right moment. So I thought ! speedometer error ? Quite an accomplishment for the New Horizon's team. Mrs K now knows what bounces around in my head. By th way, I had someone steering the vehicle