Pluto Surface Observations 2: NH Post-Encounter Phase, 10 Oct 2015- 1 Feb 2016 Options

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This thread is for discussion of NH Pluto surface observations received after 10 Oct 2015.

[Herobrine]

Was the new full MVIC crescent image rotated 3 degrees prior to being published, or is the striping/banding artefact (mostly removed in this version) not aligned with the sensor?
I also notice there was a slight change in scale between this release and the earlier one. This one appears about 0.13% smaller (about 4.5 pixels out of every 3000).

Also, @ZLD That new version of the stretched color image is fantastic.

[john_s]

This new image is in its original orientation, so yes, the residual electronic noise is tilted relative to the image rows and columns. Also, the first-released version of the image was rotated slightly to make the horizon horizontal near the skyline mountains, for maximum scenic effect.

John

[Herobrine]

This new image is in its original orientation, so yes, the residual electronic noise is tilted relative to the image rows and columns. Also, the first-released version of the image was rotated slightly to make the horizon horizontal near the skyline mountains, for maximum scenic effect.

John

Thanks! I probably should have figured as much, since the star streaks are aligned with the image and the vertical dimension of the image is consistent with what one would expect for a non-rotated image.

[Guest_MichaelPoole_*]

I have just read a part about Io in the book "Vzdálené světy I" (Distant Worlds I) by Tomáš Petrásek and Igor Duszek from 2009. This book is focused on the Jovian moons, and the chapters on Io contain some really interesting pictures and information on Io, with many references. Apparently, in a lot of places, Io is covered by sulfur dioxide snow spewed by volcanoes that also cause the signature otherworldy blue colors that we see on pictures of Io's, and a lot of those plumes are probably caused by underground deposits of sulfur dioxide (hidden just few tens or hundreds of meters below the surface and occasionally flowing up like hot springs on Earth) being boiled when lava flows into them. Some calderas on Io also display frozen SO2 that resulted from them being filled by liquid SO2 from underground springs that subsequently froze. It also had some very nice pictures of Ionian mountains, no, not volcanoes, mountains caused by tectonic activity made of rock.
Mountains like this:

https://en.wikipedia.org/wiki/Tohil_Mons#/m...:Tohil_Mons.jpg
https://en.wikipedia.org/wiki/Euboea_Montes...boea_Montes.png
http://www.gishbartimes.org/2009/02/lpsc-2...-of-hiiaka.html
https://en.wikipedia.org/wiki/List_of_mount...o_at_sunset.jpg

There is also this close-up picture of Io that strangely reminds me of Pluto's "snakeskin terrain". I couldn't find it on the Internet so I photographed it from the book by my smartphone, hope this meets fair use guidelines:
http://i11.pixs.ru/storage/4/1/4/Iocloseup...63_19323414.png

The scale is a lot closer that the snakeskin terrain, but still...

What is the relevance of this to Pluto you might say? Well, for one, the absence of a dense atmosphere does not mean the absence of liquids. Regional, small, liquid deposits can exists underground in a shallow depth. Io's atmosphere is about 1000x thinner than Pluto. It does not require for it to be a relic of a past "dense atmosphere epoch" either, as these deposits can arise by normal volcanic acitivity. Liquids leaking on the surface might freeze and boil, creating weird formations. The book also mentions that the present epoch of Io's hyperactivity might not be permanent and it might swing into and out of cycles of hyperactivity and saner volcanic acitivity. Just because there are no obvious active geysers on the side of Pluto that New Horizons imaged in high resolution does not mean it is not presently geologically active, if we count the time of the close flyby as being the time when the probe was 768 000 km or closer to Pluto (time when it took the iconic "heart" photo https://www.nasa.gov/image-feature/pluto-is...amed-the-heart), the close flyby took just below 15 hours or less than a single day. If your flyby of Earth was that short, odds are there wouldn't be any obvious active volcanos visible at a given side of the Earth. I live in a country (Slovakia) that had the last volcanic activity occuring 100 000 years ago, yet it would be silly to call Slovakia "geologically inactive" terrain. So my money is on Pluto being active right now, we've seen "remnants of cryovolcanism" on Ariel and this is definitely something entirely different.

Some violent sublimation might also occur, as apparently, it is not just the eliptical orbit that changes Pluto's temperature but the extreme axial tilt might play an even bigger role. Apparently, the summer temperatures can go into 70s in the Kelvin scale and the melting point of nitrogen is 63.15 Kelvin, which is also the boiling point in such a thin atmosphere, so the sublimation is less "slow drying over millions of years" like on Callisto and more flash boling of ice:

https://blogs.nasa.gov/pluto/2015/10/23/a-p...or-all-seasons/

A summertime high might only be “in the 70’s” as measured in Kelvins—about 330 degrees below zero Fahrenheit (minus 200 degrees Celsius).

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