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Comet Unexpectedly Brightens a Millionfold
swordgeek writes "Comet 17P/Holmes, a relatively obscure and (until a few days ago) dim object, has suddenly flared to be literally a million times brighter, going from magnitude 18 to 2.8. It is just outside of the constellation Perseus, which puts it high in the sky and ideal for viewing at this time of year. The comet still appears starlike even in binoculars but should grow to several arcminutes across over the next few nights. The comet is now readily visible to the naked eye. This is a completely unexpected once-in-a-lifetime event, so get out your finest optics (even if it's just your eyes) and go comet watching!"
i don't think we've seen a really big bright comet in how long? hasn't it been decades, or centuries even? anywhere in the world?
i mean a really big bright one that eats the whole sky
we need a big bright comet because history teaches us that warring factions oftentimes stop their fighting and lay down their arms when shocked at the sight
so we need a big bright comet pronto
intellectual property law is philosophically incoherent. it is your moral duty to ignore it or sabotage it
Perhaps I'll go look. Despite all the hype, Halley was a bust. Kohoutek may have been the comet of the century, but that was last century. I hope this one doesn't disappoint.
When our name is on the back of your car, we're behind you all the way!
I remember a group of people waiting for you. Some 32 people in some large farm house or something in California. All wearing some kind of black clothing and Nike shoes. They took your promise to come in 1999 or so and committed suicide but you are coming so late. OK atleast the rest of the believers can now die and meet you.
sed -e 's/Chuck Norris/Rajnikant/g' joke > fact
A house divided against itself cannot stand.
When the clouds clear up, and the rain stops.
Oh, right, UK.
Never.
According to SpaceWeather.com, not only did the comet brighten unexpectedly, it "... has no tail, [and] a remarkable golden color ...". Unless the geometry of the sun-earth-comet trio is such that the tail is pointing directly away from the earth, you'd think there'd be a massive tail given the million-fold increase in brightness.
Tiller's Rule: Never use a word in written form that you've only heard and never read. You will end up looking foolish.
The comet is now readily visible to the naked eye.
WARNING
Do not look into the comet with your remaining eye.
liqbase
Kwisatz Haderach
Sell the spice to CHOAM
This Mahdi took Shaddam's Throne
Looking at the last link in the summary I think we ought to be able to see it
Look for Cassiopeia ( a big and fairly obvious W or M in the sky) and track your eyes downward from it. It's going to be just down to the left of the bright star Mirfak in Perseus.
I wonder what the reason for the brightening is? Maybe it hit Voyager.
Well, the only star it's flying near is the big yellow one you see in the daytime. I haven't seen anything about the reason it got brighter, but my guess would be it has an icy core that has been gradually heating internally as it orbited closer to the sun, until suddenly it burst out as steam. If that's the case, maybe it'll get brighter as it gets closer and warmer... or maybe the lid's been taken off the pot and after a day of spewing a ton of stored-up H2O now it'll settle down and get dimmer.
(Like a balloon when something bad happens!)
This is not an eclipse, so you should be able to watch it from the UK, clouds permitting. If you are worried about latitude, you can check the low-cost flights to Spain and come to watch it from here over the weekend. I think you can see Perseus from the UK, anyway.
Comets appear bright because they start to evaporate as they approach the sun, and the sun illuminates the evaporating gas and dust.
The best guess as to why this one has suddenly brightened so much is that it has either broken apart or experienced a sudden outgassing for some other reason.
BTW, the comets we see are gravitationally bound to our solar system, so the only star they ever come close to is Sol.
A house divided against itself cannot stand.
Well, umm, the UK and the US are not that different in latitude, and as for the east-west thing, last I checked the earth makes a complete revoluion every day.
sudo ergo sum
Where's the Argo/Yamato? Tell 'em to power up the Wave Motion Gun to deal with this intergalatic menace!
I didn't think the house band in Hell would play this badly.
Obviously, It's coming right for us!
Magnitude is a log scale, with brighter objects having lower magnitudes. Like so much in astronomy, the reason is historical: when the first guy (Greek, probably) decided to categorize stars by brightness he said the brightest stars should be first magnitude, the next brightest second, and so on. Because of the nature of the human eye, the scale is logarithmic. Objects brighter than what this guy considered first magnitude thus have a magnitude of less than one, or even less than zero.
The numbers are funny (rather than -1, 0, 1, 2) because they're giving you sample objects so you can get an idea about the range of the scale.
Hope that helped!
...high in the sky and ideal for viewing at this time of year.
On what part of the planet? Northern hemosphere or southern? The Americas or Asia? What time of night (or day)?
In 1974, the American media were excitedly predicting a very bright comet named Kahoutek, and then when it appeared wrote how dissapointing the show was, that it wasn't even visible.
I was in Thailand that year, Kahoutek drowned out all the stars in half the sky there.
Some of you folks need to learn that the internet is a global phenomena and not restricted to your own country. Is this thing visible in my country (US)? What part of the sky, and what time? If I can see it, people in Australia can't.
-mcgrew
mcgrew's razor: Never attribute to stupidity that which can be explained by greedy self-interest
This comet orbits between 2.2 and 5.2 AU and it's last closest approach to the Sun was in May, 2007: http://en.wikipedia.org/wiki/17P/Holmes. An AU is the average distance between the Sun and the Earth.
Comet crusts, the dark stuff that is left over after the ice sublimates, are thought to conduct heat slowly. One theory on why we see outbursts as comets move away from the Sun, as this one is doing, is that the warming pulse from the closest approach takes time to sink down to a reservior of carbon monoxide gas which then sublimate internally and blows off fairly large chunks of the comet. Another theory is that the same thermal pulse reaches a reservior of amorphous water ice, which is more common in space than crystalline ice and thus might be present in comets since their formation. When amorphous ice is warmed, it will become crystalline and release energy because the ordered state of crystaline ice is a lower energy state. This can lead to a chain reaction of further crystallization and energy release that could lead to enough warming to cause sublimation in the interior and then do the same kind of thing as in the carbon monoxide scenario.
--
Get your power from the Sun for what you already pay now: http://mdsolar.blogspot.com/2007/01/slashdot-users-selling-solar.html
You think that's unexpected?
Wait until it suddenly changes direction!
Now thatwill be unexpected!
----------------------------------- My Other Sig Is Hilarious -----------------------------------
What about in the UK? Where would I need to look to see this thing?
Regardless of country - You would need to look up.
Visit http://ringbreak.dnd.utwente.nl/~mrjb/growingbettersoftware to download your free copy of the book
here. There was no visible tail, just a fuzzy circle.
So that's why it's going to be cloudy over my area for the foreseeable future?
Never fails.
Dedicated Cthulhu Cultist since 4523 BC.
Dr Evil: ... and so we will demand... one million dollars! (*laughs evilly*)
Henchman: Um, well, it turns out that a million dollars isn't so much money any more.
Dr Evil: Hmm. In that case... we will demand... fifty cents!!!
- First they ignore you, then they laugh at you, then ???, then profit.
?? I don't see ANY of those lines when I look into the sky at night, is there some filter/layer I need to turn on somewhere?
Try hitting Ctrl-;
kurzweil_freak
5th Kyu Genbukan Ninpo/KJJR student
Be the darkness that allows the light to shine.
To expand on this, in the night sky, Perseus looks like a rough square with four curvy lines jutting out of it, and with the northward side of the square "bent" out by a bright star. That star is Mirfak. Perseus isn't as obvious as Cassiopeia, or even Andromeda (just south of Cassiopeia), so if you're in a city and are unfamiliar with the night sky, you might have trouble locating it (just a couple miles out of town should be enough to get a clear enough view). To help orient yourself, the "feet" of Perseus, facing south, look like two triangles (a third triangle, southeast of Perseus and southwest of Andromeda, is the constellation Triangulum).
"We consider that six courts and an asylum claim are a rather odd way of returning to Sweden within a month."
Does anyone have any idea why this comet has suddenly got so much brighter?
Global warming.
The comet hasn't brightened. What you're seeing is the afterglow from the nuclear explosion that Bruce Willis set off yesterday.
You never really know how close to the edge you can go until you fall off.
You realize, of course, that being able to make a connection to a Sci-Fi book that was just published last year means your chances of ever getting a date are pretty much non-existent.
You never really know how close to the edge you can go until you fall off.
Obviously a ship starting its deceleration burn.
Invalid Checksum. Retrying.
This comet isn't exactly one to get hyped about. It's not that bright. Magnitude 3 is about as bright as the Little Dipper. You won't see it from the city and you have to know where to look to identify it from better conditions.
Of course, naked eye comets always get a brief mention in the news, even when dim, but this one caught attention because of the dramatic increase in brightness. It's all the more surprising when you consider that this is a short period comet in a relatively circular orbit. It makes it's close approach to the sun frequently, so it doesn't tend to brighten much as it makes the approach, and it has no tail. Even more remarkable, it's currently moving away from the sun, so it would normally be expected to dim, not brighten. Why? Well, it may have had an unusual outgassing event or have impacted another object. Beyond that, I don't have any good guesses.
The brightest comet in decades was McNaught, which made a show last winter. Unfortunately, it was very close to the sun, so it rose barely after sunrise and set barely after sunset and was therefore hard to observe. However, it quickly got brighter than Venus and eventually was so bright (M -6) that a clever observer in clear, dry air could spot it during the day, a scant few degrees from the sun.
It was a little more friendly to observers in the southern hemisphere, and its huge, striated tail was spectacular. Here's a picture.
Kohoutek wasn't all that bright. Probably the best observer's comet last century was Hale-Bopp, which was very photogenic and had a remarkable double tail. I wasn't alive for Halley, which has a lot of historical significance, but it's latest pass wasn't very impressive.
The /. title "Comet Unexpectedly Brightens a Millionfold" demonstrates a common mistake.
Each "fold" means a doubling, or 2 to the n'th power. For example, three-fold is 8-times. Take a piece of paper and fold it three times- unfold it and count the number of rectangles outlined by the creases. This is where the expression actually came from...
People incorrectly use the "fold" term because they think it sounds more intelligent, but they demonstrate their ignorance by misusing it.
A brighting of 2 to the millionth power would be so massive that we and our entire solar system would be almost instantly vaporized and blown away by the photons striking us.
ron
If the comet reaches Earth it is a WMD.
I'm slightly appalled. /. readers, check my grammar and links, and then click submit. Lo and behold, it gets accepted. Cool!
/. editors: If you're going to actually edit submissions (and why start now, after ignoring fundamental grammatical errors and duplicate stories for a decade?) then get it right!
I write up what I consider to be an interesting story for
Then I read what I supposedly wrote, and find that words have been put in my mouth. Specifically:
"The comet still appears starlike even in binoculars but should grow to several arcminutes across over the next few nights. "
I did NOT write that. I didn't suggest it. The comet does NOT appear starlike in binoculars at all--it's quite a clear extended disk. ONE person quoted in Sky & Telescope believes that it will expand to several arcminutes in size, but that's strictly conjecture.
Furthermore, I didn't use the word "millionfold" in my subject line. That was kdawson again.
"People who do stupid things with hazardous materials often die." -- Jim Davidson on alt.folklore.urban
You are forgetting about the major increase of light pollution in modern life. Up until electric power, it was pretty dark out at night. just looking at a clear sky with no moon was enough to create awe in the eyes of superstitious. and those comets that look faint in our skies today had tails that span the horizon. unless we have a moon sized comet heading REALLY close to us. I doubt you'll get the war ending awe that was common back in the day. they are just not going to be as impressive in our polluted skies. But don't stop dreaming on my account.
Just to be clear on something, I never used the word millionfold in my submission. That was kdawson editing my post for his own glory.
Incidentally, the term has been used both ways, and has etymologically distinct roots, so millionfold meaning 'a million times' is valid.
I can't link directly to it, at the sixth entry (-fold) at Miriam Webster's.
Nonetheless, it wasn't my word. Neither was the claim that the comet is 'starlike in binoculars.'
"People who do stupid things with hazardous materials often die." -- Jim Davidson on alt.folklore.urban
Johnny Rico: I'm from Buenos Aires, and I say kill 'em all!
"I only speak the truth"
Karma: null(Mostly affected by an unassigned variable)
Webster's Revised Unabridged Dictionary Threefold \Three"fold`\, a. [OE. [thorn]reofald; cf. AS. [thorn]r[=i]feald.] Consisting of three, or thrice repeated; triple; as, threefold justice.
http://en.wiktionary.org/wiki/threefold threefold 1. three times as great 2. triple
Similar definitions for twofold. Do the "fold" rules change after three?Nope. This comet made its closest approach to the sun back in May. It's now moving away from the sun. It also follows a relatively circular orbit compared to most bright comets, so significant changes in brightness are unexpected.
However, there may have been an unusually large pocket of vapor that form some reason burst out at this point (out-gassing), or it might have been hit by a smaller object.
Nothing. Only when you get outside of civilization are you afflicted with the light pollution from stars hundreds of light years away. Don't worry, this pollution, while unsettling if you weren't expecting it, has no permanent ill effects and clears up again after you return to civilization.
Help poke pirates in the eyepatch, arr.