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Fraser
2005-Feb-21, 05:31 PM
SUMMARY: A massive gamma ray flare flashed so brightly in December that it briefly outshone the full Moon. Even though it occurred 50,000 light-years away, the flare demonstrated the power of these events, disrupting the Earth's ionosphere. The flare occurred on the surface of a rapidly spinning, highly magnetic neutron star called a magnetar, which can release tremendous amounts of energy through a process called magnetic reconnection. We're lucky the flare occurred so far away; if it had happened within 10 light-years, it could have destroyed the Earth's ozone layer.

View full article (http://www.universetoday.com/am/publish/gamma_ray_flare.html)

What do you think about this story? Post your comments below.

piersdad
2005-Feb-21, 05:40 PM
some amazing things in the universe its hard to imagine magnetic fields that strong.
maybe one day we will find out the relationship between magnetisim and gravity as it appears this star has magnetisim more predominant than gravity???

contact
2005-Feb-21, 08:58 PM
"Astronomically speaking, this explosion happened
in our backyard. If it were in our living room,
we'd be in big trouble!"

Hopefully there was nobody else's living room out there!
Maybe otherwise SETI will receive extraterrestrial
"MAYDAY, MAYDAY ... " signals during the next weeks.
Now we know another spot in our Milky Way, where
we don't need to look for life anymore.

Sounds like the story of an interstellar Tsunami.

zephyr46
2005-Feb-22, 03:02 AM
Thats the impression I got from reading the paper.

With a 10 ly radius of destruction!

This event was also in Sagitarius, 50000 lys! Thats halfway across the galaxy.

For the Aliens fans out there, one could see such large scale astronomical events bringing surrounding civilisations together ( like the worldwide response to the Tsunami! )

Greg
2005-Feb-22, 06:12 AM
If a magnetar can produce a grb of this intensity, imagine what a similar event would look like emanating from a SMBH! I imagine such an event would be at least one order of magnitude more powerful sterilizing an area 100 light years across or more. It's kind of a bummer for anyone who wants to colonize near the center of the galaxy where objects such as this magnetar are much more abundant.

OCTracker
2005-Feb-22, 06:46 AM
OK, your article says the flare "disrupted the earth's ionosphere".

Presumably, it's doing the same thing to extrasolar planets all over the galaxy. I'm wondering if that effect could be observed through any existing telescopes or if the effect would be too faint to observe (or would be lost in the glare of the planet's star).

The flare has already come and gone for us, but any planets away from the direct line between us and the flare should show the effect in a few more months or years, as the light has to travel a little extra distance to get to us.

If we can see it happening, it'd be a shame to waste the opportunity.

Eric Vaxxine
2005-Feb-22, 10:08 AM
Dinosaur extinction comes to mind.

alfchemist
2005-Feb-22, 10:59 AM
[QUOTE]Maybe otherwise SETI will receive extraterrestrial
"MAYDAY, MAYDAY ... " signals during the next weeks.
Now we know another spot in our Milky Way, where
we don't need to look for life anymore.

If there's an advance civilization near the magnetar, they would have predicted this would happen and maybe they have left their sanctuary. So i guess, the next best place for them is EARTH! :D

dave_f
2005-Feb-22, 03:00 PM
Originally posted by OCTracker@Feb 22 2005, 01:46 AM
OK, your article says the flare "disrupted the earth's ionosphere".

Presumably, it's doing the same thing to extrasolar planets all over the galaxy. I'm wondering if that effect could be observed through any existing telescopes or if the effect would be too faint to observe (or would be lost in the glare of the planet's star).

The flare has already come and gone for us, but any planets away from the direct line between us and the flare should show the effect in a few more months or years, as the light has to travel a little extra distance to get to us.

If we can see it happening, it'd be a shame to waste the opportunity.
If it can be done I'd say do it. But I do see some problems here with implementation. :)

The extra-solar planets we do see are generally (with few exceptions) Jupiter-class or brown dwarf type planets. Also these planets, because of the detection methods used, are close to their suns (they're easier to find because that makes their suns wobble more). So in addition to the intense radiation and other effects the planets themselves tend to generate, they have to sit by a star constantly pelting them with radiation.

Let me just say that some distant magnetar throwing off a very large flare is going to be a drop in the bucket compared to what they already experience.

Also, the timing has to be perfect, to within a few minutes. The intense burst was short lived. Even if a measurable change could be measured, it would have to be nailed down to the minute (it only affected Earth's atmosphere for about 5 minutes before the most of the created ions got their electrons back). We just aren't that accurate with our extra-solar distance readings. ;)

Not at present, anyways. Cool idea though. If it could be worked it would be a nice demonstration of a light echo at a galactic scale. B)

zephyr46
2005-Feb-23, 01:53 AM
This sgr sounds familiar (http://citebase.eprints.org/cgi-bin/citations?id=oai:arXiv.org:astro-ph/9502038), LBV 1806-20 (http://www.solstation.com/x-objects/1806-20.htm) made headlines last year as the biggest star known.

http://www.solstation.com/x-objects/1806-20m.jpg

A very interesting region!

A catalog of SGRs (http://www.ioffe.ru/LEA/SGR/Catalog/) with a history of bursts.

SGR 1806-20 (http://www.gsfc.nasa.gov/topstory/20021030strongestmag.html) also made news (November 4, 2002) as the strongest magnetic source known in the Universe, (well when I have been to the ends of the Universe, I will believe that :) ), I don't think we have found one stronger, so I think the record stands.

http://antwrp.gsfc.nasa.gov/apod/image/0502/magnetarburst_mallozzi_big.jpg

APOD (http://antwrp.gsfc.nasa.gov/apod/ap050221.html)

vet
2005-Mar-01, 10:03 PM
close GRBs have concerned me as sources of mass-extinction for years. such thoughts were given little consideration until recently, as previous GRBs were distant. now, perhaps we may shift funding to sub-surface lunar colonization, vs. killing one another. while we may.