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New Views of Supernova 1987A Reveal Giant Dust Factory
New submitter ihtoit writes "Astronomers using the ALMA radio telescope in Chile have released images and data showing the oft-postulated but unobserved (until now) dust shell ejected by the supernova remnant SN1987A. 'We have found a remarkably large dust mass concentrated in the central part of the ejecta from a relatively young and nearby supernova,' astronomer Remy Indebetouw, of the National Radio Astronomy Observatory (NRAO) and the University of Virginia, said in a statement. 'This is the first time we've been able to really image where the dust has formed, which is important in understanding the evolution of galaxies.' SN1987A was the first cataloged supernova event in our Galactic neighborhood in 1987. It lies 168,000 light years (987 quadrillion miles) away in the Large Magellanic Cloud, which means that at the time of the explosion, woolly mammoths still roamed Europe and Mitochondrial Eve saw her first sunrise."
From the article, the significance: "'Really early galaxies are incredibly dusty and this dust plays a major role in the evolution of galaxies,' Mikako Matsuura, a scientist associated with the study ... said ... 'Today we know dust can be created in several ways, but in the early universe most of it must have come from supernovas. We finally have direct evidence to support that theory.'"
Global Dusting! "'Really early galaxies are incredibly dusty and this dust plays a major role in the evolution of galaxies,' Our next goal is to create a vacuum large enough to slow down global dusting and the creation of new galaxies. Sources cite that Spaceballs has offered their maid services for a fair price.
Today we know dust can be created in several ways, but in the early universe most of it must have come from supernovas.
Supernovas, as every landlord can tell you, are awful tenants. They trash the property for light years around, leave dust bunnies the size of nebulae under the furniture, and clog up the drains with heavy elements. Yeah, we know they have a lot of pent-up energy to blow off, but I was the one who cleaned up after Cygnus X-1 was evicted and I found this huge friggin' hole they'd punched into the side of the cosmos. I mean, seriously kids, have some pride, it's your spacetime too. I can't even patch it up with drywall: the stuff just crumples up and disappears. Now the security deposit's gone and I'm out $3B to Home Depot. Next time I'm only renting to brown dwarfs.
Koans and fables for the software engineer
as it turns out, they were viewing it thru an SN7404 and so the image was actually inverted.
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"It is now safe to switch off your computer."
I dislike astronomical distances because it's hard to imagine what they're like. 160,000 light years is 134,000 SSU (solar system units, the width of the solar system) or 1.6 GU (galactic units, the width of the galaxy). Hope this help!
for dust thou art, and unto dust shalt thou return Genesis 3:19
A statement like:
"It lies 168,000 light years (987 quadrillion miles) away ..., which means that at the time of the explosion, woolly mammoths still roamed Europe ...."
is highly misleading in the framework of Special Relativity: There is no universally agreed upon "at the (same) time" in Special Relativity for distant events.
It is just as valid to say that the explosion took place at the same time the car was invented. It is just a question of the observer's frame of reference (that's why it is called "Relativity").
The only thing that is non negotiable here is that there is a causal link between the space-time event of the nova explosion and the the space-time event of the arrival of the light emitted during the explosion on earth. There is no observer that can break this causality. But there is even a frame of reference that puts these two events at the same spot in space and time!
For the more mathematically minded: Time and space distances depend on the observer. What is fixed is the space-time distance D, namely:
D = sqrt( (x2-x1)^2 + (y2-y1)^2 + (z2-z1)^2 -c^2*(t2-t1)^2 )
which happens to be zero for causally linked events.
In 1987-1988 I was traveling around Peru ($2000 lasted a lot longer then) for five months. I read about the supernova in an English-language newspaper someone had left in the hotel lobby, and had tried to see it but there was too much light in Cusco or Arequipa to even distinguish the Large Magellanic Cloud.
The bus between Cusco and Puno ran only at night, but it was supposed to be non-stop and I hoped that light levels in Puno were low enough to maybe be able to walk down the shoreline of Lake Titicaca to where I could see something. Shortly after crossing 4000-meter high La Raya pass the bus blew a tire. Most of the bus just snuggled down and went back to sleep, while a few got off to take the unscheduled bathroom break while the tire was changed. I walked away from the lights of the bus and over the crest of a knoll and looked up into a blacker, more star-studded sky than I had ever imagined. Absolutely frelling stunning.
After I recovered from the initial sight I was very quickly able to find the Large Magellanic Cloud, and offset from the center there was the first naked-eye visible supernova in over 900 years. I stayed out under that really amazing sky until I was shivering so badly from the cold that I couldn't hold my binoculars steady.
"Think about how stupid the average person is. Now, realise that half of them are dumber than that." - George Carlin