Starship Asterisk*

RocketRon wrote:
Did New Horizons have radar, to determine that 100 km thickness ?

https://en.wikipedia.org/wiki/Pluto#Internal_structure wrote:

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<<Pluto's density is 1.860±0.013 g/cm3. Because the decay of radioactive elements would eventually heat the ices enough for the rock to separate from them, scientists expect that Pluto's internal structure is differentiated, with the rocky material having settled into a dense core surrounded by a mantle of water ice. The diameter of the core is hypothesized to be approximately 1700 km, 70% of Pluto's diameter. It is possible that such heating continues today, creating a subsurface ocean of liquid water some 100 to 180 km thick at the core–mantle boundary. In September 2016, scientists at Brown University simulated the impact believed to have formed Sputnik Planitia, and showed that it may have been the result of liquid water upwelling from below after the collision, implying the existence of a subsurface ocean at least 100 km deep.>>

https://en.wikipedia.org/wiki/Sputnik_Planitia wrote:
<<Sputnik Planitia may have originated as an impact basin that subsequently collected volatile ices. Alternatively, it has been suggested that the accumulation of ices in this location depressed the surface there, leading to formation of a basin via a positive feedback process without an impact.

The accumulation of several kilometers of nitrogen ice in the basin may have resulted from the positive temperature gradient of Pluto's atmosphere, which would make a topographic depression a cold trap.

A high seasonal thermal inertia of Pluto's surface is an important driver of deposition of nitrogen ice at low latitudes, which receive less annual insolation than Pluto's polar regions due to its high obliquity. The accumulation of ice would likely then have made Sputnik Planitia a positive gravity anomaly, which could have caused polar wander, reorienting the spin axis of Pluto to put the planitia near the Pluto-Charon tidal axis (the minimum-energy configuration). Sputnik Planitia is presently close to the anti-Charon point on Pluto, a result that has less than a 10% probability of arising by chance.>>

https://en.wikipedia.org/wiki/Moon wrote:
<<The concentration of maria on the Near Side likely reflects the substantially thicker crust of the highlands of the Far Side, which may have formed in a slow-velocity impact of a second moon of Earth a few tens of millions of years after their formation. The far side of the lunar surface is on average about 1.9 km higher than that of the near side. Almost all maria are on the near side of the Moon, and cover 31% of the surface of the near side, compared with 2% of the far side. This is thought to be due to a concentration of heat-producing elements under the crust on the near side, seen on geochemical maps obtained by Lunar Prospector's gamma-ray spectrometer, which would have caused the underlying mantle to heat up, partially melt, rise to the surface and erupt. Most of the Moon's mare basalts erupted during the Imbrian period, 3.0–3.5 billion years ago, although some radiometrically dated samples are as old as 4.2 billion years.

In 2014 NASA announced "widespread evidence of young lunar volcanism" at 70 irregular mare patches identified by the Lunar Reconnaissance Orbiter, some less than 50 million years old. This raises the possibility of a much warmer lunar mantle than previously believed, at least on the near side where the deep crust is substantially warmer due to the greater concentration of radioactive elements. Just prior to this, evidence has been presented for 2–10 million years younger basaltic volcanism inside Lowell crater, Orientale basin, located in the transition zone between the near and far sides of the Moon. An initially hotter mantle and/or local enrichment of heat-producing elements in the mantle could be responsible for prolonged activities also on the far side in the Orientale basin.>>

neufer wrote:

https://en.wikipedia.org/wiki/Sputnik_Planitia wrote:

orin stepanek wrote:I believe water ice is very common in the universe; so it would be no surprise to find it on Pluto!

RocketRon wrote:

orin stepanek wrote:I believe water ice is very common in the universe; so it would be no surprise to find it on Pluto! 8-) :?

Has anyone seen any evidence of water/ice outside even of our solar system ?

Chris Peterson wrote:

RocketRon wrote:

orin stepanek wrote:I believe water ice is very common in the universe; so it would be no surprise to find it on Pluto!

Has anyone seen any evidence of water/ice outside even of our solar system ?

Yes, we observe water everywhere in the Universe.

RocketRon wrote:So HOW is this water detected 'everywhere in the universe' actually detected ???
Water wouldn't have emission spectra, since it wouldn't be as glowing plasma inside any suns ?