2. How come Tom Ridge hasn't raised the alert condition to Orange?
Whew! Thanks Rosanne!! Wouldn't want you to jump the gun here or anything.
Update On 'Threatening' Supernova
New Scientist Story
From Karin Sandstrom
Re: The New Scientist Article
5-25-2
Hi,I'm Karin, the one quoted in this article as having discovered the supernova progenitor. I just wanted to let you all know to pay very little attention to the article. The reporter has taken one fact: that this might be a good candidate for a Type Ia supernova, and constructed a big mess out of it. I am very embarassed by this so I just wanted to clear up a few things.
First, I did NOTHING in the discovery process. I was just writing my senior thesis on white dwarfs and happened to study this system. It was discovered in 1993 by two separate groups of scientists (Landsman et al 1993, and Wonnacott et al 1993) They found the mass to be 1.15 solar masses, which is relatively large for a white dwarf star, but not the "just shy" of the Chandrasekhar limit that the reporter says. It is 0.3 times the mass of the sun shy of the limit, and that is a lot of mass. Lots and lots of people have studied this system since then, and many have commented on its possibilities for a supernova. All that I did in this story is to mention the system to a scientist here at Harvard who happens to simulate the evolution of a binary system towards a supernova and then mention in in a public talk about my thesis when a New Scientist reporter happened to be in the audience. The reporter got very excited and wrote this article, and left out the actual work that is being done on the evolutionary scenarios to sensationalize the possibility of a near earth supernova.
Second, what we have found, if anything, is that by the time that the white dwarf star has accreted enough mass from its companion to exceed the Chandrasekhar limit of 1.4 solar masses, it will be at least 10 kiloparsecs from earth, which is well on its way to the other side of the galaxy. The star will not pose any threat at all to earth. This is also hundreds of millions to billions of years in the future. I think the interesting part of this story is the terrible state of scientific news reporting in some popular journals. We discussed these problems extensively with the reporter and they were completely disregarded in the final version. Be on the lookout for our letter to the editor if you are interested. If anyone would like to know more about this, I'd be happy to explain what we really think is going on...unless you are a reporter, in which case don't bother...I'm done with them.
Thanks, Karin Sandstrom
"First to set your minds at rest we may have more than a few million years:
Hello, Regarding the supernova article...
This was posted to Slashdot (yes, yes, I know, it's just Slashdot) in response to this story:
-------------------------Which relieves our minds something wonderful and reassures us that the usual state of reporting is where it has been for a while.">> I'm Karin, the one quoted in this article as having discovered the supernova progenitor. I just wanted to let you all know to pay very little attention to the article. The reporter has taken one fact: that this might be a good candidate for a Type Ia supernova, and constructed a big mess out of it. I am very embarassed by this so I just wanted to clear up a few things.
First, I did NOTHING in the discovery process. I was just writing my senior thesis on white dwarfs and happened to study this system. It was discovered in 1993 by two separate groups of scientists (Landsman et al 1993, and Wonnacott et al 1993) They found the mass to be 1.15 solar masses, which is relatively large for a white dwarf star, but not the "just shy" of the Chandrasekhar limit that the reporter says. It is 0.3 times the mass of the sun shy of the limit, and that is a lot of mass. Lots and lots of people have studied this system since then, and many have commented on its possibilities for a supernova. All that I did in this story is to mention the system to a scientist here at Harvard who happens to simulate the evolution of a binary system towards a supernova and then mention in in a public talk about my thesis when a New Scientist reporter happened to be in the audience.
The reporter got very excited and wrote this article, and left out the actual work that is being done on the evolutionary scenarios to sensationalize the possibility of a near earth supernova. Second, what we have found, if anything, is that by the time that the white dwarf star has accreted enough mass from its companion to exceed the Chandrasekhar limit of 1.4 solar masses, it will be at least 10 kiloparsecs from earth, which is well on its way to the other side of the galaxy. The star will not pose any threat at all to earth. This is also hundreds of millions to billions of years in the future.
I think the interesting part of this story is the terrible state of scientific news reporting in some popular journals. We discussed these problems extensively with the reporter and they were completely disregarded in the final version. Be on the lookout for our letter to the editor if you are interested.
If anyone would like to know more about this, I'd be happy to explain what we really think is going on...unless you are a reporter, in which case don't bother...I'm done with them. Thanks, Karin Sandstrom
-------------------------
Best regards,
Lee Plaisted Skeptical Maine-iac ---
"...religions are a democracy of beliefs while science is a dictatorship of facts." --Ludwig Krippahl
There's always a catch on these things.
The Chandra
Yep, or it could have happened 149 years ago, but the light and radiation just hasn't gotten here yet.
Fortunately, it will take time for HR 8210 to accumulate the mass it needs. Preliminary calculations by Rosanne di Stefano at the Harvard-Smithsonian Center suggest this may take hundreds of millions of years
Doesn't sound to me like it should. When the companion goes red giant, the "dwarf" could grab up the necessary matter essentially instaneously, on the scale of such things, which might mean years, but surely not hundreds of million of years. Of course we don't know when the companion will go red giant, assuming that that didn't happen a 149 years ago of course. Well, it sound like it will be quite a show when it happens, something to look forward to, other than the possibily of getting thourghly fried that is. :)
Let's hope so. Mankind has outlived its usefulness.
I believe that the Chandrasekar limit applies to a star before it collapses. It's the act of compression that generates the energy to cause a star to blow. Adding more mass to a white dwarf would do nothing to cause a nova, super or otherwise.
Who is the New Scientist? The article is written for a popular audience, not for the astronomy student's peers. Has anybody seen this info published in a peer review journal? "Science" comes to mind, or even Scientific American, at least S.A. is written for a better educated popular audience.
Someone reading a Bible in the student union?
The "Nike" wearing Y2K nutjobs that didn't jump aboard Hale-Bobbit might find use for their freeze dried foods yet!!!! Just have them make sure the shelf life is a couple of million years. :-)
Eastern time, mind you...