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Pluto's Haze
Today brings another release of images from NASA's New Horizons probe. This time, it includes an image taken seven hours after closest approach, when the probe was looking back at Pluto. It captured the dwarf planet in silhouette: the body of the planet is in darkness, but the atmosphere is luminous with deflected sunlight. "A preliminary analysis of the image shows two distinct layers of haze -- one about 50 miles (80 kilometers) above the surface and the other at an altitude of about 30 miles (50 kilometers)." Before this picture, scientists didn't expect to see such haze more than 30 kilometers above the surface.
Other findings released today include preliminary indications that Pluto's atmospheric pressure has dropped sharply from early observations. This may indicate that the atmosphere is in the process of freezing and falling to Pluto's surface. Finally, new close-up pictures of the surface transmitted back to Earth show direct evidence of nitrogen ice floes reminiscent of glacier movement on Earth. The dwarf planet also seems to be rich in methane ice and carbon dioxide ice.
Other findings released today include preliminary indications that Pluto's atmospheric pressure has dropped sharply from early observations. This may indicate that the atmosphere is in the process of freezing and falling to Pluto's surface. Finally, new close-up pictures of the surface transmitted back to Earth show direct evidence of nitrogen ice floes reminiscent of glacier movement on Earth. The dwarf planet also seems to be rich in methane ice and carbon dioxide ice.
I suppose I could do the math, but since I'm lazy... if it were possible for you to be standing on the daylight side of Pluto, does anyone know how bright/dark would it be? Is there enough light that you'd be able to see the terrain, at least dimly?
#DeleteChrome
Freezing and falling to Pluto's surface... if you were that far from the sun, you'd do it to.
filled with micro-aggression.
Pluto haze all in our brains
Latest readings don't seem the same
An exciting time, you all agree
For studyin' exometeorology
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Prisencolinensinainciusol. Ol Rait!
Normally I'm not into feeding the trolls... but I've started to look forward to the MOO cow posts, this one is a nice modification lol
timeo Danaos, et dona ferentis
Sadly, the haze is reddish-brown, rather than Purple Haze.
Really? I mean, fucking really? Everyone gnu that penguins saw "awk". Torvalds sed so.
New Horizons' communication channel is very slow. About 1 killobit (not kilobyte) per second. My guess is they don't really have more data to "release" yet.
happens on other planets too
Can't upgrade the transmitters on the New Horizons spacecraft, which due to power constraints can only transmit 2 Kb/s (bits, not bytes) at most. The only reason we have pictures at all is because the PI recognized the need for something to put on the front page of the New York Times to represent what has happened. They're getting a trickle of data, most of which is scientific in nature. For now, up until late September, we'll have to content ourselves with the few extremely pretty JPEGs that were sent back ahead of some of the other instruments' data.
Because you're too proud of your ignorance to google that,
"The short answer to that question is: Pluto is far away -- very far away, more than 30 times Earth's distance from the Sun -- so New Horizons' radio signal is weak. Weak signal means low data rates: at the moment, New Horizons can transmit at most 1 kilobit per second. (Note that spacecraft communications are typically measured in bits, not bytes; 1 kilobit is only 125 bytes.) Even at these low data rates, only the Deep Space Network's very largest, 70-meter dishes can detect New Horizons' faint signal." -Emily Lakdawalla
Ultraviolent sunlight chemically converts hazes into tholins, the dark hydrocarbons that color Pluto’s surface.
Did we find Clockwork Orange?
Silence is a state of mime.
Well, new Horizons *is* 10 years old, and rather too far to be upgraded. They'd love to upgrade the DSN, but that takes money, which they're not exactly flush with (certainly not for maintenance - upkeep money doesn't make its way to the pork barrels efficiently enough). What do you suggest?
Is anyone else embarrassed that NASA uses miles as its primary unit of measure?
-- I was raised on the command line, bitch
It has an atmosphere at all.
"When Pluto is closer to the Sun in its orbit, the warmth from the Sun heats up the frozen ices of nitrogen, methane and carbon monoxide on Pluto's surface. These ices vaporize and form a temporary atmosphere. When Pluto moves farther from the Sun, the atmosphere freezes and falls back onto Pluto's surface."
http://coolcosmos.ipac.caltech...
"If any question why we died, Tell them because our fathers lied."
As I understand it, one hypothesis about Pluto is that its atmosphere will disappear completely when it gets far enough away from the sun. Its orbit is eccentric enough to allow for huge variability in the amount of solar irradiance. This is similar in some respects to comets, which start to melt as they approach the sun and freeze again as they travel back into the outer solar system. It's also cold enough in the martian winter that we see processes not entirely unlike this, where there is a significant decrease in atmospheric pressure as carbon dioxide freezes to form clouds and falls as snow near the poles. Pluto is just a much more extreme situation. These observations seem to support that a large part of Pluto's atmosphere freezes as it moves farther from the sun.
Did you find out on a man date?
From the photos it looks like the mountains have pushed up through the ice. I wonder if that is how the 'Moated Mountain" formed, nitrogen ice eroding the geology.
I have to say this is an appropriate use of the word 'amazing' - Thank you NASA (and the American taxpayer)
My ism, it's full of beliefs.
If you don't show appreciation, you deserve Comcast
Table-ized A.I.
" but the atmosphere is luminous with deflected sunlight. "
The light in the linked image was almost certainly not deflected, but scattered by pluto's tenuous atmosphere. This can be surmised from a few different lines of argument.
1. Pluto's atmosphere is probably too tenuous to significantly deflect light. At 2 million miles away, Pluto subtends about 1mrad, so light would need to deflect about half that amount to intercept the spacecraft. even if this were possible, the light regions in the image would only reveal the level in the atmosphere that gave just the right amount of deflection to hit the spacecraft (i.e. An Einstein ring, but not via gravity).
2. Note also that at pluto's distance the sun only subtends about .2mrad, so the picture does not show a near solar eclipse.
3. Although atmospheric density profiles could be inferred from light deflection (see shadowgraph or schlieren), the analysis is much more difficult compared with light scattering, where the intensity is proportional to the number and type of scatters.
The best explanation I've read for the youth of the surface is that Pluto's elliptical orbit results in a heat-and-cool cycle that pumps semi-liquid and/or soft frozen gasses around.
The relative densities between different materials changes during the near/far cycle, causing push-pull action that gradually squeezes and pumps shit around.
Table-ized A.I.
Jupiter would be able to mug and beat the shit out of everybody, including Saturn. Pluto may have an advantage in being too small to notice among the carnage.
Table-ized A.I.
"1 killobit".
Using frequencies lower than infra dead, presumably.
H/T to Douglas Adams, RIP.
"Wait. Something's happening. It's opening up! My God, it's full of apricots!"
NASA releases one picture a day. Either the hard is too old or the soft is too slow (or the staff is incompetent). Please upgrade something!
Photoshop takes time.
Anyone have a mirror of this stuff?
== Jez ==
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