New Horizons Will Have Little Time to Measure Pluto’s Atmosphere

Re:New Horizons Will Have Little Time to Measure Pluto’s Atm... by eganist on Tuesday June 30, 2015 @07:30PM (#9809050)

Before anybody opines with "How could Pluto have an atmosphere when it's less massive than the moon (which has no atmosphere)?", it's worth noting that the moon does in fact have an atmosphere.

Interestingly, NASA speculates that Pluto's surface pressure is around 3 µbar, whereas they state that the moon's surface pressure at night is dramatically less than that, at 3.0 × 10^-9 µbar. I'm curious to see what New Horizons' measurements will reveal.

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Re:New Horizons Will Have Little Time to Measure Pluto’s Atm... by hcles on Tuesday June 30, 2015 @08:45PM (#9809310)

If we're talking outliers then Titan, the largest moon of Saturn has a surface atmospheric pressure 1.4x more than Earth's, while being 2.3% of Earth's weight

And then there's Venus' atmospheric pressure :-)

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Re:New Horizons Will Have Little Time to Measure Pluto’s Atm... by Osmium on Tuesday June 30, 2015 @07:33PM (#9809070)

Curious, but how much of an effect would temperature have on a planet's ability to retain an atmosphere? A colder planet of equal size will presumably be capable of maintaining a thicker atmosphere, but I'm not sure if that'd be a significant factor in this case or not.

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Re:New Horizons Will Have Little Time to Measure Pluto’s Atm... by Sharlin on Wednesday July 01, 2015 @08:38AM (#9811425)

Proximity to the sun is a crucial attribute with respect to density of an atmosphere, both due to heat input (hot molecules escape easier) and solar wind density (energetic particles strip away molecules in collisions.)

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