Posted on 10/04/2010 10:17:03 AM PDT by TaraP
BIG GREEN COMET: The icy nucleus of comet 103P/Hartley 2 measures no more than a couple of kilometers across. That tiny nugget, however, is surrounded by an vast atmosphere of gas more than 150,000 km in diameter--about the same size as the planet Jupiter! And it's coming our way. Amateur astronomer Nick Howes sends this picture of the approaching comet from Cherhill, WIltshire UK:
"I photographed the comet on Oct. 1st using a 4-inch refractor," says Howes. "Four hours of exposure time revealed not only the comet's vast green atmosphere but also an emerging tail." Howes describes the processing of the data here.
At present, the comet is a 7th-magnitude object best seen through telescopes. (We recommend the Comet Hunter.) The view will improve, perhaps even to naked-eye visibility, as the comet glides by Earth only 11 million miles away on Oct. 20th.
Two weeks after Comet Hartley has its close encounter with Earth, NASA will have a close encounter with the comet. The Deep Impact/EPOXI spacecraft is hurtling toward Comet Hartley now, and on Nov. 4th it will fly 435 miles from the comet's active icy nucleus. The encounter will mark only the fifth time in history that a spacecraft has been close enough to image a comet's core.
Until then, amateur astronomers can monitor the comet as it glides through the constellation Cassiopeia in the evening sky. A finder chart from Sky and Telescope shows the comet passing by a variety of stars and deep-sky objects, offering many photo-ops in the nights ahead.
Certainly interesting and worth paying some attention to, imho.
thx.
Comet - It will make your teeth turn green
Comet - It tastes like gasoline
Comet - It will make you vomit
So get some Comet, and vomit, today
Indeed. The fact that the comet is green reminded me of the "green mist" which trailed the capsules launched by the Martians.
Of course, the segment of the intro I quoted was narrated by the late Richard Burton. Lead vocalist for the sung portions was Justin Hayward of the Moody Blues.
The icy nucleus of comet 103P/Hartley 2 measures no more than a couple of kilometers across. That tiny nugget, however, is surrounded by an vast atmosphere of gas more than 150,000 km in diameter—
Pretty unusual, it doesn’t sound like outgassing but
what kind of mass would you need to hold that atmosphere
in place, to travel along with the nucleus??
.
Nully, check out # 15.
That makes sense (unlike most of the rest of this thread). Thanks.
It’s not being held in place. It is diffusing out into space.
Correct you are.
And, Parson Nathaniel was none other than Phil Lynott, lead man of Thin Lizzy.
I had that LP when I was a lad, and most recently, found it online, and it is securely on my Ipod now....ULLA
Still doesn’t make sense, a kilometer sized object is
not going to have enough mass to hold an atmosphere
even temporarily, where did it come from?
I’m confused.
That’s a bit like asking where the water around an ice cube came from.
I happen to be listening to the Blackstone Audiobooks production right now.
I’m amused that the Brit reading it (Christopher Hurt) pronounces ‘ULLA’ as ‘allah’.
That stuff around an ice cube is called scotch.
So all this atmosphere we are talking about came
from the frozen solid nucleus? It was originally
much larger and made up of solidified gas that is
now difusing into space, and much faster as it
nears the sun?
Be interesting to see the photos.
Yes. At sea level 1 cubic mile of ice makes 1700 cubic miles of water vapor. Multiply that volume by a bunch to get how many cubic miles of near-vacuum vapor that equals!
I think it's a little more than 'remarkable'. I don't think we actually have a good scientific explanation.
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