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Comet ISON Nears Date With Sun
riverat1 writes "Now visible in the morning sky, comet ISON will swing around the Sun on November 28. ISON will pass 730,000 km above the surface of the Sun at closest approach (Mercury's perihelion distance is 46 million km). If it survives its near brush with the Sun it could provide a spectacular sky show from December into January. This NASA timeline shows that ISON will be the most observed comet ever as instruments ranging from a balloon carried telescope to the Hubble Space Telescope to the STEREO satellites will be brought into play. Lowell Observatory astronomer Matthew Knight lays out three possibilities for ISON: spontaneous disintegration before it gets to the Sun (less than 1% chance); disintegration as it rounds the Sun; or survival. If it survives, its closest approach to Earth will be on December 26 at about 1/3 of an AU."
How visible will it be to the unaided eye? And where will it be the most visible? I was in southern Thailand when this comet came by, and was puzzled when the newspapers said it was "disappointing". It was the brightest thing in the night sky except the moon where I was.
Free Martian Whores!
Considering 1/3 of an AU is only slightly closer than Mars' closest approach to Earth, and several million miles more than Venus' closest approach to Earth, I'd say it's close enough to 0 to be considered a rounding error.
Day early, day late...either way, looks like you just follow the damn thing, find some kid in the straw, and call him the sone of a deity.
My bet: he'll be covered in meatballs and pasta.
Is it just my observation, or are there way too many stupid people in the world?
That word does not mean what you think it means.
It's bombarded so aggressively, it's having its surface ripped off it to create that enormous tail, and it's suffering from ever greater gravitational tidal forces - that's about as far as you can get from happening without apparent external infuence.
Also FatPhil on SoylentNews, id 863
Wikipedia says that thing was fourth magnitude when visible in the night sky: that's not very bright. But it can *seem* bright in good dark skies. Dark skies were, of course, much more common in the seventies than they are now. Light pollution eats comet tails for breakfast.
Now, few comments (nice typo...COMETS) are really impressive in the night sky. Hale-Bopp was one exception. Most are impressive only close to the sun - this was true of Kohoutek, and will be true of ISON if it survives.
The predictions for ISON place it very close to Kohoutek in terms of brightness, actually. This brightness is for the closest approach to the sun - meaning best viewing is right after sunset, or just before sunrise. If things pan out, we might get to see a huge, bright tail against a backdrop of somewhat dark sky.
Khan, is that you? (Still not thinking three-dimensionally, huh?)
Ezekiel 23:20
Somebody queue the "three wise men", of Biblical fame.
Since before recorded history,
Comets have been a wonder, and also a harbinger of doom. Humans back then tied the defeat of a major battle, crop failure to the passing of a comet as it was a convenient event for all to remember, given there were no clocks invented, but the solar cycle. I wonder if this comet becomes, as predicted a blazing all-can-see comet, some of the still existing lesser-developed cultures will interpret its passing as such. Such cultures still exist! There are over 500 languages on New Guinea. These people are so removed from modern society, they have never seen a "white man" nor his clothes. Most assured a comet to them would be today as our clocks had a 13th hour/ time stopped, and birds fall out of the sky, for example.
Curious if any sociologists plan on visiting such "primitive people" and researching their reactions to the comet as odds are we will have to wait an unknown length of time to the next possible chance of research!
Old news. Tell me when Comet ADSL is heading our way.
What distinguishes comets is not only their insanely eccentric orbits but also their predominantly icy makeup, right? Will it still have any ice or other volatiles after such a close pass with the sun? If all that volatile mass burns off, won't that significantly alter its orbit thereafter?
See this link for some stunning imaging by amateurs: http://www.cometisonnews.com/
and this one for some serious work by 'just' an amateur: http://brucegary.net/ISON/
and this one which was one of the earliest to plot data (that I knew of): http://www.aerith.net/comet/catalog/2012S1/2012S1.html
Personally, from its outburst a couple of days ago, I expect it to become negative magnitude easily (the more negative, the brighter).
20s is far too long at 70-200 mm, you'll turn the stars into streaks.
Set to the highest ISO you can, set the exposure to about 2s...3s, take about 100 shots, and stack them (lots of free apps available, or photoshop, etc.)
You want the best image, that's how you get it.
For instance, here's a shot of a MUCH dimmer and smaller comet made just that way at 200mm; check out how you can see both the ion and dust tails:
http://www.flickr.com/photos/48447736@N00/4695946008/
(you can see that the 2.5s exposure there was even a little too long... the stars are visibly elongated. You can "fix" that in software, but it's kinda cheating.)
I've fallen off your lawn, and I can't get up.
They show a couple comets as they go around the sun between 28 and 38 seconds into the video. The orbit should stay outside the circle whose radius is the perihelion except when the comet is at the perihelion itself. Since it's inside the circle, it's closer to the sun than where they're putting the perihelion.
with all the *son technologies, it is hard to keep track :p
Never antropomorphize computers, they do not like that
The Hubble Telescope, back in August 2000, captured the broken remnants of the of the Comet Linear which exploded
http://hubblesite.org/newscenter/archive/releases/2000/27
Picture of the remnants is at http://imgsrc.hubblesite.org/hu/db/images/hs-2000-27-a-print.jpg
Muchas Gracias, Señor Edward Snowden !