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Hubble Snaps Pix Of Dying Supernova
The Hubble has taken some great pictures of a supernova according to CNN. You can get a more indepth article, and more pictures from Space.com story on the same subject. Purty explosions!
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This big enough? :)
(got from here)
A supernova (as in this instance) is a dying Star not a dying supernova. The supernova is actually quite young.
My $0.02 will always be worth more than your â0.02, so
To quote the CNN/Reuters article: Timed to precede the U.S. Independence Day holiday on Thursday, the newly released image was made in two exposures, one in January 2000, the other in January 2002.
And what will everybody remember? That nice supernova that was photographed by Hubble the Great just before July 4th.
Nice PR job, NASA. I appreciate it. Sincerely.
Here's the Hubble homepage and here is the original version at few defferent sizes, formats, and borders.
As any reasonably intelligent and non-pedantic slashdot reader knows, the process of a star's supernova has a beginning, which one might call the "birth" of the supernova, and an end.... which might be called the "death" of the supernova.
The pictured supernova is near its end, or "death". That means, one might say, it's "dying".
I'm sick of nit-picky dorks karma-whoring with word games. We knew what the phrase meant... let it drop.
Cretin - a powerful and flexible CD reencoder
What, are they using it to do traffic reports now?
That passing line in the space.com article about lack of symmetry connects to some interesting physics.
Scientists were embarrassed for a while by the fact that the most realistic computer models of supernovae would fizzle instead of exploding. A simulated shock wave would start from the core, but with the mass of a star falling in on it the shock wave always stalled.
Then they switched from 1-dimensional simulations to 2-dimensional simulations when they got hold of enough computer power. Turns out there's an overturn instability. The shock wave can't make it out *on average* but does locally. Some small fluctuation gets bigger as the shock wave pounds at it and that direction gets more of the action.
Which explained an old observation that a lot of supernova remnants were moving pretty fast. Among other things, the supernova is a rocket engine with peak power equal to the luminosity of a galaxy, and (forgive me) astronomical amounts of propellant.
That was a qualitative insight from a quantitative increase in computer power.
Screw bottlerockets, i want me one of them!
As an astronomer who studies Cassiopeia A- I will admit that this picture doesn't really say alot to the public other than "Hey pretty picture" and it is NOT a dying star! The reason it is of interest is because the Chandra Space Telescope first saw evidence of a point source at Cas A's center indicating a remnant of the supernova explosion that hasn't been seen in any other wavelengths. Much as a few of us have tried we have not been able to find a source in optical or infrared for the x-ray point source indicating that the progenitor star that made the supernova may infact be a black hole rather than a neutron star which is what makes this object so interesting.
http://www.seds.org/~spider/spider/Vars/casA.html
You make a remarkably ill-informed post for someone with the arrogance to give themselves a nick like PhysicsGenius.
Your assertions that only projects which will make HST "look good" get time, and that approved HST projects must conform to the narrow vision of a small number of people, are demonstrably false. Anyone who knows the first thing about modern telescope scheduling in general (and HST's scheduling in particular), knows that it's just about the opposite of what you claim.
Observing time on HST is not determined by "bureaucrats" nor by "politicians". The Time Allocation Committee (TAC) is comprised of active research astronomers, who judge the huge number of proposals on scientific merit. The TAC members are different every observing semester, and they all come from outside of STScI (the institute which "runs" HST). Indeed, those who are selected to be on the TAC have a wide variety of interests and perspectives on how "important" a particular project is. I'm sure you can understand how this diversity of opinion leads to a more objective judgement by the TAC as a whole. In other words, the rotating TAC system does a good job of reflecting the opinion of the entire astronomical community.
In short, you have no idea what you're talking about. Why would a "PhysicsGenius" make up slanderous statements about one of the greatest scientific instruments ever constructed? The mind boggles...
Liberal (adj.): Free from bigotry; open to progress; tolerant of others.
Is the from the dept of ... a reference to the third Sten book, The Court of a Thousand Suns, by Chris Bunch and Allan Cole?
The colors in this particular image are especially misleading.
In most HST "pretty-picture" images, the colors are at least representative of reality. You take three images, through "blue", "green" and "red" filters, then stack them, with each layer driving the appropriate R,G,B value of the color composite. The result may be more saturated than reality, but you get at least some idea of how it would look to your eye.
However, this image is a stack of "narrow-band" images, centered on particular atomic emission lines. These narrow-band images are incredibly useful scientifically, because they let you study the energetics and chemistry inside the SN remnant, as well as the shock conditions of the gas. However, the colors are assigned arbitrarily, and have no connection to how the object would actually look.
Unfortunately I saw no caveat to this effect in either the CNN article (no suprise) nor the space.com article (mildly disappointing).
I mean, why not add a phrase in there like: "In reality, Cas A is not so colorful. The vivid colors are added to the image to help scientists map out different chemicals and their ionization states, which allows them to determine the strength of the original explosion, and how it has evolved to its present state."
Liberal (adj.): Free from bigotry; open to progress; tolerant of others.
I just can't believe it. First Princess Di and now the paparazzi are using Hubble to rob the dignity of a dying star.
--
As a matter of fact, I am a lawyer. But I play an actor on TV.
Multiply by 3600 sec/hour and you will see that one light-hour is about 671 million miles.
So if a supernova shockwave is moving at 45 million miles an hour, that's 45/671 or about 6.7% the speed of light in a vaccuum.
It works in metric too of course..
1 light-second is about 300,000 km/s (a third of a million km/s)
1 light-hour is then about 1000 million km/s, and 72/1000 or 7/100 gives you about 0.07c.
So next time you see a number of million kilometers per hour from CNN you can just divide it by ten and that is the percentage of the speed of light.
I think when we talk about this scale of velocity we need something better than "million miles/kilometers per second" and more tangible than a fraction of c.
1 milli-light = 1 mc = 0.001 c = 1 million km/sec = 0.67 million miles = 1 gigameter.
It is useful for CNN and promotion of space to the public because instead of saying "72 million km per hour" (which should be 72 gigameters/hour which abbreviated would unfortunately look like gram-meters/hour..)
..You can just say 72 milli-lights.
For a seemingly limitless supply of "CAS A" pictures, check this out:
Right Ascension 23 : 23.4 (h:m)
Declination +58 : 50 (deg:m)
I am a Karma Library.
Check this out. I have a friend who's fired a number of them off, he says that they're every bit as impressive as the website claims.
Unfortunatly, I don't have enough money to buy ~600 sparklers, so no bomb this fourth. :(
Jordan Bettis
``Wherever you go, there's another stupid sigfile quote.''It's more likely to be from Mad Magazine where many of the jokes and articles are "From the $foo Department".
Mad Magazine remains one of the few credible printed journals left in the US (and apart from the "National Inquirer" it's probably the only decent publication sill out there). Go grab a copy!
OK, to clarify, I'm asking if the specific dept (the explosion-of-a-thousand-suns dept.) was inspired by The Court of a Thousand Suns. Although I do appreciate the explanation involving MAD magazine. It's been a while since I've read that.
When converting to meters per second from meters per hour, you'll want to divide by 3600, not times by 3600.
Just in case you weren't joking, I thought I'd clear that up...
Let's not stir that bag of worms...