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Huge Star Quake Rocks Milky Way
SJrX writes "The BBC is reporting that scientists have detected "the biggest explosion observed by humans within [the past 400 years]". The explosion luckily occured about 50,000 light years away form us, on the far side of the Milky Way, as the article goes on to say that had the explosion been within 10 light years of us, it "would possibly have triggered a mass extinction.""
I though that the New scientist article on it was a bit more informative.
10 light years is really close... Thats like only 3 times the distance form us to the sun.
Considering that it takes 8 mins for light from the sun to reach Earth, I think your calculations are a bit off.
365 days x 24 hours x 60 mins = 525600 mins/year
525600 mins/year x 10 years = 5256000 mins
5256000 mins / 8 mins = 6.57x10^6 times
Therefore 10 light years is actually 6.57x10^6 times the distance from us to the sun.
QED
Live forever, or die trying.
Seriously, this has to be the most bizzare astronomy story tagline I've ever read. I figured this was the submitter's quote, or possibly the article writer - nope, it was from one of the physicists.
Then you didn't read the New Scientist article which had this gem:
But Christopher Thompson, an astrophysicist at the Canadian Institute for Theoretical Physics, says that may not be so. The neutron star in question is rare magnetar, with a magnetic field so strong it could wipe a credit card clean from a distance of 160,000 kilometres. And this magnetar is even rarer yet, one of three "soft gamma repeaters" (SGRs) in the Milky Way.
Ya know, IANAPOAPOA (I Am Not A Physicist Or AstroPhysicist or Astronomer) but I'm willing to bet that if I were 160,000 kilometers from this object, or even our sun, I might be worried about other things than my credit cards getting wiped.
cheap labor conservatives - they want to keep you hungry enough to be thankful for minimum wage.
Given that the "constants" in the Drake equation are order-of-magnitude estimates and that explosions like this are very rare, I don't think it will be a real impovement.
There is no good and bad. There is only cause and effect.
It depends on your frame of reference. IIRC, from the viewpoint of the gamma ray photons themselves, there was no delay at all between the time of the starquake and reaching earth.
A sad day indeed. Drudge Repor "News for nerds. stuff that matters".
Ok I get it now... they mean "mass" as in "total" or "complete," not mass as a noun. Sorry for the double-post.
Esoteric reference.
Hiroshima was approximately 1x10^20 watts This is 1x10^40
Ya know, IANAPOAPOA (I Am Not A Physicist Or AstroPhysicist or Astronomer) but I'm willing to bet that if I were 160,000 kilometers from this object, or even our sun, I might be worried about other things than my credit cards getting wiped.
That's why YANAPOAPOA. I can imagine the interview.
"If you were 160,000 kilometers from this black hole... we'll, you'd be in space, so you'd be dead! So don't go there!"
Magnetic fields are difficult to characterize. What are you going to do, tell people the field is 1000000000000 Tesla? (Yawn, what's a Tesla?) You can't compare magnetic fields to hens eggs or Libraries of Congress. The only thing you can really do is compare them to a field strength that people are intuitively familiar with- like a refrigerator magnet's field, an MRI field, or a field sufficient to wipe magnetic cards. Refrigerator magnets and MRIs come in a variety of field strengths. Plus, smartasses would make comments about refrigerators and magnetic imaging machines in space.
That must be the Dynamite Monkey by Random McEric, originally on Fark's The last thing you'll ever see photoshop contest.
10 light years is 3 times the distance from earth to the sun? Light takes approx. 8 minutes to reach the earth from the sun. Thus, the earth is 8 light-minutes from the sun. Thus, the earth is not 3.33- light years from the sun.
"A language that doesn't affect the way you think about programming, is not worth knowing" - Alan Perlis
If the sun was only 10 kilometres from your house, a mass extinction might occur.
Seriously, this has to be the most bizzare astronomy story tagline I've ever read. I figured this was the submitter's quote, or possibly the article writer - nope, it was from one of the physicists.
Why is it bizarre? When I read it I understood what he meant and why he said it. Light years are big. For anything ten light years distant to have a measurable effect on the Earth is pretty amazing!
The radiation intensity at the surface of the Sun is 63,000,000 watts per square meter. (Your 10 km makes no real difference.) The intensity 10 light years (10^17 m) away from a 10^40 watt source would be approx. 100,000 watts per square meter. So you'd have to be 25 solar radii away from the Sun for its radiation intensity to be equivalent to this magnetar if it were ten light years distant. (For comparison, mercury orbits at about 86 solar radii.) Nitpickers may note that the Sun is mostly radiating UV through IR, and the magnetar's energy is brief and in the gamma ray spectrum, but this is still impressive.
It does not look like FARK's link to the Dynamite Monkey is hosted anymore. It is too good to miss:
M onkey.jpg
http://www.banishedsouls.org/635850d13f/Dynamite_
The Drake equation IS an equation. That's the right term for it in science, hard or soft. The number of technological civilizations in the galaxy we can communicate with is equal to the product of the probabilites/numbers on the other side of the equal sign. Just because some of those numbers/probabilites are uncertain does not stop it from being an equation. For instance, it isn't a proportionality or an approximation (unless you actually start pluggin in approximate numbers). And I wouldn't say that the term equation is a "title." You're reading too much into this.
These sort of estimation games are really valuable in lots of branches of science and often lead to insight. Enrico Fermi used to do this all the time, which is especially relvant since his "Fermi Paradox" about how it's strange we haven't encountered alien intelligences is the same sort of thing that Drake formalized.
Professor of Astronomy, Author of Spider Star & Star Dragon (Tor)
???
I guess I've observed there too many times for such a joke to be funny. Lick Observatory is named after James Lick who funded the establishment of the Observatory back in the 1890s. It's an interesting place -- the first observatory put on a mountaintop (it was originally going to be in downtown San Francisco, imagine that). His ashes are kept in a memorial under the 36 inch refractor.
It's a spectacularly pretty location, overlooking the bay, and the old observatory portion is all marble and brass, 19th century elegance. I got married there and the reception was great (band, catered dinner, and the 36 inch refractor was available for guest viewing).
The road to Lick from San Jose is a very twisty 19 miles. The mules, originally used to haul material there, wouldn't go up more than a six degree incline, so it's switchback city. This also makes it a popular road for bicyclists. I used to be annoyed with them, since I had to go there semi-regularly for work and often drove while sleepy. I imagined I'd come around a corner and have a tired rider at zero speed in the middle of the lane. They paid me back though one time. I was sitting in the dining room eating breakfast one afternoon, and these two riders and a car pulled up. The car driver switched off to ride a bike, and she stepped in front of the window and stripped out of all her clothes while the milk dripped off my spoon, caught halfway to my mouth. Good times.
Professor of Astronomy, Author of Spider Star & Star Dragon (Tor)
Actually, it's more complicated. Yes, the radiation/heating would not be uniform, but the bigger killer would be from the destruction of chemicals like ozone in the upper atmosphere that protects us from the sun's radiation. The details are kind of complicated, and depends on exact distances, fluxes, and spectral energy distrubution. And atmospheric science.
Yeah, excuse me, big science nit-picker tonight.
Professor of Astronomy, Author of Spider Star & Star Dragon (Tor)
You put the comma in the wrong place. So sayeth Google!
+ per+light+year
http://www.google.com/search?q=astronomical+units
1 light year = 63 239.6717 Astronomical Units
Say the density of such stars is uniform in the galaxy. Then the frequency of such explosions within 10 ly from us should be something like
(1/400) * (10/50000)^3
if we assume that the frequency of these things within 50000ly is on the order of 400 years. That is... wait... *tiptiptip* 2*10^-14, i.e. once (or twice) in about 10 trillion years (the universe has an age of a few 10^9 years!).
Well, the galaxy is more like a disc. So let's try the same with an exponent of 2 instead of 3. This gives 1*10^-10, still less then one of these "mass estinction" events in the age of the universe. Not much to fear here...
This is a series of emails that discuss the burst. Interesting posts include the following:
There were a series of small bursts observed before the big one, but no one seems to have realized that they were precursors until after the big one arrived. "During 21 December more than 30 SGR-like bursts were detected by Konus-Wind and Helicon-Coronas-F" satellites.
The burst was detected by the Mars Odyssey spacecraft. "A very preliminary analysis indicates that the arrival time at Odyssey is indeed consistent with an arrival direction from SGR1806-20."
There is also discussion of an Earth-orbiting satellite that did not have a direct view of the flare; however, it picked up a faint echo 7.70 seconds after everyone else saw it. "This value corresponds exactly to burst travelling time from the Wind to the Moon and back to the Coronas-F."
Finally, serendipious observations were made by spacecraft whose primary mission is solar observation. "The SGR was 5 degrees from RHESSI's pointing axis which was directed toward the Sun."
Nothing for 6-digit uids?
Your trying to do an apples to oranges comparison. A Watt is a unit of power. The bomb is usually measured in kilotons or megatons, energy units. But I'll try:
P = E/t
A Watt is a Joule per second.
The energy released by a ton of TNT exploding as a unit of energy is 4.2 x 10^9 Joules. So divide 10^39 (10,000 trillion trillion trillion watts) by 4.2x10^9 and get 2.38095238 x 10^29 tons of TNT per second. That's 2.38 x 10^26 kilotons or 2.38 x 10^23 megatons.
The Hiroshima bomb released about 12.5 kilotons of TNT of energy. That means at one point the magnetar was releasing the energy at the rate of about 1.9 x 10^25 (19,000,000,000,000,000,000,000,000)Hiroshima bombs per second.
Of course assuming all my math is correct...
Any sufficiently advanced influence is indistinguishable from control.
My understanding is, at the densities we're talking about, the force of gravity is stronger than the nuclear forces of the atoms -- you get funny things like electron orbits being heavily deformed.
A spinning neutron star that's charged on one side more than another due to gravity pulling electrons around, would induce a magnetic field. Probably a damn strong one too, seeing the forces involved.
Mitochondria contain DNA for one, they are basically full blown prokaryotic organisms, very similar to extant species of aerobic microbes.
I did not make any reference to time at all and the time it takes to create an intelligent complicated device is not relevant. What is relevant however is that the device contains an incredible amount of INFORMATION, which CANNOT, according information theory arise from randomness, but only from another source of information.
While the total entropy of a closed system must rise, that doesn't mean that there can't be isolated pockets of entropy reduction (information creation), balanced by regions of increased randomness. For example the sun is graduallly messing itself up to allow the earth to be more ordered.
The interesting question is where all the potential inherent in the big bang came from.
In other words only if they are next door right this minute and not past the noisy stage we're starting to get out of.
Are we?
If you're assesment of our current detection abilities isn't shy at least an order of magnitude seti would have to be pretty lucky indeed (lottery levels at least) to pick up anything.
Only if we were watching out for everyday TV and radio signals. If we looked for a directed signal we could detect it half way across the galaxy.
The thing about space is it's not big, but mindshatteringly hugely enormously big.
Well, not really in terms of SETI. Even a very slow moving civilisation that drifted across space at far less than sub-light speed, spending a long time colonising each new solar system, could have filled the entire galaxy dozens of times over. If not organisms, then robotic probes could have done this. We are nearly at the stage of being able to do this. The galaxy looks empty.