Pluto's "Thick" Air Isn't Going Anywhere

astroengine writes "When the proposition for NASA's New Horizons mission to Pluto was put forward, there was an air of urgency. The dwarf planet is moving away from the Sun in its eccentric orbit, so astronomers were concerned that the Plutonian atmosphere would freeze out and collapse onto the surface as fresh nitrogen-methane snow before they could get a spacecraft out there to observe it. But according to new research [arXiv], it appears there's little risk of a Pluto air freeze-out. From recent occultation measurements, it appears the atmosphere is becoming denser and more buoyant, meaning it will remain as an atmosphere all (Pluto) year 'round — 248 Earth years long."

Comments

Can you imagine living on Pluto?

[ArcadeMan]

(Refresh fedex.com web page)
Oh man, my package has been rescheduled to arrive "tomorrow".

Re:Can you imagine living on Pluto?

[Anonymous Coward]

Delivery Service no longer extended to dwarf planets, package will be available for pickup for the next 5 business days at the nearest FedEx location (Mercury)

Re:Can you imagine living on Pluto?

[beatljuice]

A week late isn't too bad. (Pluto takes 6. 39 Earth days to rotate on its axis.)

Re:Can you imagine living on Pluto?

[mythosaz]

Meh. Only about 6.3 Earth days to make a Pluto day.

Getting your prison sentence increased by a year... ...that'd be a bummer.

Re:Can you imagine living on Pluto?

[Austrian Anarchy]

FedEx is not bad there, but waiting on NASA to fulfill your AAA request is another matter.

Re:Can you imagine living on Pluto?

[icebike]

Exactly!

There’s no point acting all surprised about it. All the planning charts and discontinuance notices have been on display in your local planning
department in Alpha Centauri for fifty of your Earth years, so you’ve had plenty of time to lodge any formal complaint and it’s far too late to start
making a fuss about it now.

Re:Can you imagine living on Pluto?

[icebike]

But most prison sentences are given in months, and months are based on the Moon's orbit around its (dwarf) Planet, and Charon orbits Pluto every 6.387230 days. So that would be a blessing, no?

Re:Can you imagine living on Pluto?

[mythosaz]

touché

Re:Can you imagine living on Pluto?

[Sique]

How long are business days on Mercury? As the Mercury has a very strange synchronism between its own rotation and the orbit around the Sun, the same Sun constellation on the Mercury's sky reappears every 176 earth days.

Re:Can you imagine living on Pluto?

[dgatwood]

No, no, it's a Pluto week, which is about a month and a half in Earth time. :-D

Re: Can you imagine living on Pluto?

[Sique]

Actually, it's not tidal locking. It's more complicated. Mercury makes three turns while rotating twice around the Sun. And exactly so.

Re:Can you imagine living on Pluto?

[Tablizer]

Pluto is a dog, so it's calculated in "dog years".

Re:Can you imagine living on Pluto?

[tokiko]

Pluto's solar day is 6.39 earth days long, so for Pluto "tomorrow" would just be similar to "next week" here on Earth.

While sitting on Pluto and trying to refresh the fedex.com web page hosted on Earth, however, would be significantly more frustrating. A one-way radio transmission between the two currently takes 3.66 hours (increase that to 4.5 hours when New Horizons finally gets there.) I'm pretty sure a TCP connection attempt is going to timeout before the handshake process finishes.

Re:Can you imagine living on Pluto?

[BTWR]

This is why I love Slashdot

Re:Can you imagine living on Pluto?

[K. S. Kyosuke]

Delivery Service no longer extended to dwarf planets, package will be available for pickup for the next 5 business days at the nearest FedEx location (Mercury)

Five synodic (solar) business days on Mercury? As in, 880 Earth business days? No need to hurry, then.

Denser AND more buoyant?

[xvedejas]

Isn't "denser and more buoyant" a contradiction?

Re:Denser AND more buoyant?

[aevan]

In this sense it's that the atmosphere has a greater buoyancy force to oppose gravity.
i.e. XKCD's Cessna crashes 1 second later than usual :P

Re:Denser AND more buoyant?

[michelcolman]

Buoyancy apparently has several contradictory meanings. "Buoyant" can mean "able to float" but also "able to cause things to float". Therefore, denser fluids are both more AND less buoyant. Does that help? ;-)

snow on a dwarf planet

[Covalent]

It will be interesting to see if DH spots any snow...so far as I know we haven't spotted active snowing on any body other than Earth.

Re: snow on a dwarf planet

[Covalent]

Damn you autocorrect. Meant NH - New Horizons.

Re:snow on a dwarf planet

[Anonymous Coward]

Mars has carbon dioxide snow at the poles, and Titan probably has hydrocarbon snow in some form. I don't think the latter has been observed directly though.

Re:snow on a dwarf planet

[umafuckit]

And there appears to be methane snow coating Titan: http://en.wikipedia.org/wiki/Titan_(moon) Rain too, by the looks of things: http://www.wired.com/wiredscience/2011/03/titan-april-showers/

Re:snow on a dwarf planet

[Covalent]

Yes, but have we seen it snowING?

Further down someone mentioned Enceladus. That's a pretty good example, but I would argue that's not snow so much as volcanic (geyseric?) fallout. Not really atmospheric precipitation in the general sense.

Titan also appears to have snow and rain, though we haven't really seen it fall (though not for lack of trying).

Interestingly, on all of these worlds the substance being "snowed" is different. Water on Earth, Carbon Dioxide on Mars, Methane on Titan, and potentially Nitrogen on Pluto. I love science.

Hurry To Pluto Now!

[Ukab the Great]

Before it turns into a tropical paradise with a race of 36-24-36 sex-starved tribewomen who live next to lakes of single malt scotch.

Re:Hurry To Pluto Now!

[Neil Boekend]

Meh, at a max surface temperature of 55K they can't be all that hot. And they would be complaining of the cold all the time.

I blame Global Warming...

[sconeu]

It appears the atmosphere is becoming denser and more buoyant,

Vacation time?

[Tablizer]

When the proposition for NASA's New Horizons mission to Pluto was put forward, there was an air of urgency. The dwarf planet is moving away from the Sun in its eccentric orbit, so astronomers were concerned that the Plutonian atmosphere would freeze out and collapse onto the surface as fresh nitrogen-methane snow before they could get a spacecraft out there to observe it. But according to new research [arXiv], it appears there's little risk of a Pluto air freeze-out.

So now the probe can stop for an extended break at Uranus. Check out the mall, have drinks with the Uranians, make fun of Neptune's name, get an instrument boom manicure, etc.

The NASA shutdown furlough may last that long anyhow.

The Pluto site

[wooferhound]

Here is the New Horzens website http://pluto.jhuapl.edu/

Denser will make landing easier

[Herve5]

With a denser atmosphere (rather than none), it'll become easier indeed to brake and land.
When for instance you compare atmospheric entry and landing within the Earth atmosphere and the Martian one, the main difficulty on Mars is the much less dense atmosphere: aerobraking, transonic parachute deployment, end-of-trajectory thrusters all happen in a matter of dozens of seconds on Mars, while on Earth you have many minutes at least.

The denser atmosphere the best for safe arrival ;-)

(and that explains, too, the many crashes on Mars)

I participated in the Titan landing for Cassini/Huygens : I clearly remember the Titan atmosphere as a "thick" one, like on Earth (now we had other issues at the time, among others the terrible uncertainty on gas composition itself).
But I'm close to consider landing on Mars, though, is harder than on Titan.

How exactly will it be on Pluto, I hope to see ;-)

Re:Denser will make landing easier

[wooferhound]

The New Horizons mission is a Flyby, not a Landing . . .