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New Views of Supernova 1987A Reveal Giant Dust Factory

Unknown Lamer posted about 6 months ago | from the someone-forgot-to-sweep dept.

Space 39

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.'"

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39 comments

Anticipating the new scare in mainstream media (3, Funny)

BisuDagger (3458447) | about 6 months ago | (#45887543)

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.

Re:Anticipating the new scare in mainstream media (1)

cyberchondriac (456626) | about 6 months ago | (#45887617)

That would be Galactic Dusting; Global Dusting would refer to a single planet, possibly during it's accretion phase. [/pendantism]

Re:Anticipating the new scare in mainstream media (1)

Thanshin (1188877) | about 6 months ago | (#45887725)

*pedantism

Re:Anticipating the new scare in mainstream media (1)

cyberchondriac (456626) | about 6 months ago | (#45888857)

Oops.. right. I can't even blame autocorrect.

Re:Anticipating the new scare in mainstream media (1)

BisuDagger (3458447) | about 6 months ago | (#45888865)

The UN tends to set their goals small. Best to start with one planet. There's a whole middle east full of dust threatening to form galaxies.

Lame. (0)

Anonymous Coward | about 6 months ago | (#45897597)

Really, what did you think you were doing there?

Solely and only being a smartarse.

Keep your yapper shut in future and let the adults talk.

They're like your mom (1)

i kan reed (749298) | about 6 months ago | (#45887545)

You have unimaginably gigantic explosions and these scientists just say "Boy we really need to dust now."

Re:They're like your mom (1)

dotancohen (1015143) | about 6 months ago | (#45890949)

You have unimaginably gigantic explosions and these scientists just say "Boy we really need to dust now."

At least your mom writes dates in her diary entries. None of the blog's posts have dates, so when you're reading them you have no idea if the info is one week new or ten years out of date.

What a relieve (0)

Anonymous Coward | about 6 months ago | (#45887665)

"Today we know dust can be created in several ways"

I'm glad to hear that. Otherwise I would have to fear that I have a supernova in my room.

Friggin' supernovas AGAIN. (5, Funny)

QilessQi (2044624) | about 6 months ago | (#45887723)

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.

Re:Friggin' supernovas AGAIN. (2)

Brickwall (985910) | about 6 months ago | (#45888107)

Mellow out, man. All you need is a really, really big Roomba..

Re:Friggin' supernovas AGAIN. (0)

Anonymous Coward | about 6 months ago | (#45888255)

Or switch MegaMaid from blow to suck!

Re:Friggin' supernovas AGAIN. (0)

Anonymous Coward | about 6 months ago | (#45888279)

How in the hell could a latin dance help to clean up the cosmos?

Re:Friggin' supernovas AGAIN. (1)

El_Oscuro (1022477) | about 6 months ago | (#45891647)

I am pretty sure the Spaceballs fleet can handle it.

Re:Friggin' supernovas AGAIN. (1)

steelfood (895457) | about 6 months ago | (#45890021)

Next time I'm only renting to brown dwarfs.

That's a direct violation of the Fair Housing Act, Section 804(a).

false alarm (4, Funny)

TheGratefulNet (143330) | about 6 months ago | (#45887737)

as it turns out, they were viewing it thru an SN7404 and so the image was actually inverted.

Re:false alarm (1)

hawkfish (8978) | about 6 months ago | (#45898585)

as it turns out, they were viewing it thru an SN7404 and so the image was actually inverted.

Ah, another nerd from the 1970s! I'm getting all sniffly about my Heathkit digital breadboarding um thingo with the LEDs!

More dusty and polluted than China's cities? (0)

Anonymous Coward | about 6 months ago | (#45887747)

I highly doubt it.

other planets exhibit this behavior (0)

nimbius (983462) | about 6 months ago | (#45887801)

Earth periodically produces giant dust factories. Microsoft, Blackberry, and AT&T are all prime examples. Theres even a dust factory called John McCain, whos thought to have existed for millenia.

Re:other planets exhibit this behavior (0)

Anonymous Coward | about 6 months ago | (#45890453)

Soon someone in China will streal the process and be making dust for the mass market using cheap labor. China being so much closer will undercut the universe by saving on shipping.

China: for all you dust needs.

is it far? (2)

noh8rz10 (2716597) | about 6 months ago | (#45887869)

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!

Re:is it far? (0)

Anonymous Coward | about 6 months ago | (#45888409)

Not an astronomer but due maintain a passive interest; but isn't SSU not nailed down? Like what defines the edge of the solar system? Is it the edge of the sun's gravitational well? Is it the heliosphere? Is it the heliopause? The Edge of the Oort Cloud? The edge of the Kuiper belt? I always thought that's still kind of up for debate, but the variance between those things is so huge that which one you use would vastly change the actual distance of an SSU. Heck, the solar system isn't even round, so width (a line) would vary depending on where and what point you draw it through. So what exactly is an SSU?

Re:is it far? (1)

noh8rz10 (2716597) | about 6 months ago | (#45894489)

it's a yardstick, don't overthink it. Also I made up the terms SSU and GU. Do you think they'll catch on?

and Mitochondrial Eve saw her first sunrise (1)

Overzeetop (214511) | about 6 months ago | (#45888131)

Really? Are you sure it wasn't the first sunrise? I mean, 168,000 years...give or take 6 hours?

dust (4, Informative)

mrego (912393) | about 6 months ago | (#45888213)

for dust thou art, and unto dust shalt thou return Genesis 3:19

Re:dust (1)

TheGratefulNet (143330) | about 6 months ago | (#45894599)

the lamb lies down on broadway.

(also Genesis)

Re:dust (0)

Anonymous Coward | about 6 months ago | (#45895745)

This is the world we live in, and these are the hands we're given

(A more real Genesis, insofar as it actually exists and isn't a fiction made up to maintain control)

Re:dust (1)

hawkfish (8978) | about 6 months ago | (#45898611)

This is the world we live in, and these are the hands we're given

(A more real Genesis, insofar as it actually exists and isn't a fiction made up to maintain control)

Oh, come on, even Dawkins keeps the KJV around because he loves the poetry and quotes [wikipedia.org] it all the time.

Einstein says: "at the time of"? You are wrong! (2)

Pseunodym (1454239) | about 6 months ago | (#45888307)

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.

Re:Einstein says: "at the time of"? You are wrong! (1)

wonkey_monkey (2592601) | about 6 months ago | (#45888795)

A statement like ... is highly misleading in the framework of Special Relativity

But it's also perfectly reasonable in the framework of an article about a celestial event that occurred on our intergalactic doorstep at no great relative velocity. You didn't even need to go as far as you did - surely the mere phrase "It lies 168,000 light years away" is equally misleading in the light of SR.

It is just a question of the observer's frame of reference (that's why it is called "Relativity").

While you are technically correct, which is the best kind of correct, I don't think it's too churlish to allow the frame of reference to go unspecified.

But there is even a frame of reference that puts these two events at the same spot in space and time!

Same spot in space, or same spot in time. But not both, surely?

Or does every event overlap when you're a photon?

D = sqrt( (x2-x1)^2 + (y2-y1)^2 + (z2-z1)^2 - c^2*(t2-t1)^2 )

It's amazing how much that sneaky little minus sign (right before c^2, it's in bold here but you'd never know it) implies for our universe. Have you read The Clockwork Rocket [amazon.co.uk] ?

Re:Einstein says: "at the time of"? You are wrong! (0)

Anonymous Coward | about 6 months ago | (#45903593)

On the Minkowski line element written in GP as "D = sqrt( (x2-x1)^2 + (y2-y1)^2 + (z2-z1)^2 - c^2*(t2-t1)^2 )"

It's amazing how much that sneaky little minus sign (right before c^2, it's in bold here but you'd never know it) implies for our universe.

In the form above it is better to think of "-c" as the proportionality constant between the timelike and spacelike axes, even though it is rarely written down that way (for instance when using geometrized units such that at least c=1). It is the constant c that is interesting rather than the sign, which simply has to be the opposite (one also often sees a -,-,-,+ (or +,-,-,-) sign convention in use, rather than the +,+,+,- one above).

A typical example of where one sees "-c" more clearly is in "ds^2 = -c^2 dt^2 + dr^2 + r^2 d\Omega^2" where d\Omega^2 = d\theta^2 + \sin^2\theta \d\phi^2; this is the Minkowski metric on spherical coordinates.

Other metrics -- there are many -- move the "c" around within the equation, and the sign usually does not get closely bound up with the "c" constant, mostly because it is more convenient to move the sign when you expect the reader knows what "c" is in line-elements (which in general relativity is subject to democratization, i.e., it need not be or even represent notionally the speed of light in a vacuum, which is rather different mathematically and conceptually from special relativity, even though one often sees the flat space metric therein).

The "-c" before the dt in the flat-space metric simply means that there is a linear correspondence between spacelike distances timelike ones, which is exactly possible only in the complete absence of spacetime curvature (from gravitation or acceleration), but which is a good enough approximation in many circumstances. However, those circumstances do not include very large scale separations between objects (e.g. over ranges of billions of light-years) since the metric expansion of space means that our spacetime is highly curved; an accurate distance metric in those circumstances will have a non-linear relationship between "dt" and the overall spacelike distance.

However, answering your question extremely literally, and ignoring that the metric signature is in use with *metrics* in GR, the difference in sign in the flat space equation at the top means simply that things that you determine far away in space are also *in your past*. However, in GR there one has coordinate freedom and enormous latitude with line elements (which is important given that the contributions to the metric (in the tensor field sense) are not always well-defined; we don't know the equation of state for the dark sector, for example), and while it would take some contrivance and substantial curvature, one could see a metric where there is no sign difference. Alcubierre and others have played with that sort of thing while studying 3+1 formalisms. By comparison, in Special Relativity, the concept that things far away are in your past is a restatement of the second postulate, namely that the speed of light in vacuum is invariant in all inertial frames. General Relativity, however, does not concern itself with inertial frames whatsoever, and the speed of light only sets the boundary of one of an arbitrary number of causal cones. However, the relativity principle (viz., local physics is governed by the theory of special relativity), which is always under scrutiny in extreme conditions such as near the event horizons of black holes, and upon which GR does not fundamentally *rely*, does elevate "c"'s status somewhat. The equivalence principle is ultimately the fundamentally important part of General Relativity, namely that one cannot tell locally whether one is feeling gravity or some other type of acceleration. Since acceleration is alien to Special Relativity (the "inertial" part of inertial frames means no acceleration, and that's what makes the theory "special" rather than "general"), the difference is fairly substantial.

Finally, the rough answer to your questions to the GP are essentially that "frames" aren't part of GR, and the system is so filled with equivalences that one often studies the mathematics of general relativity by concocting a wide variety of observers who, when comparing notes, would disagree violently with each other about the same event. Which of the observers is "right"? None of them! All of them! That's the point of relativity, and it is a very sharp one in GR, which strives to be a rigorous mathematical framework to relate dramatically differing actual observations (or hypothetical observations) to one another.

Re:Einstein says: "at the time of"? You are wrong! (0)

Anonymous Coward | about 6 months ago | (#45889097)

There is no universally agreed upon [frame]

Of course not, but there certainly is a frame used by the vast majority of people, especially for near by astronomy and those that would read such articles.

Re:Einstein says: "at the time of"? You are wrong! (0)

Anonymous Coward | about 6 months ago | (#45898321)

For those of you too dense to be parsing the above two discussions:

Special Relativity relates space and time through distance; an event very far away will be observed a long time from when it actually happened (but you are just getting the new now).

As such, a statement like the above is more accurate when read like "It lies 168,000 light years (987 quadrillion miles) away ..., which means that at the time when the light from the explosion reached Earth, woolly mammoths still roamed Europe ....".

The discussion that there is "no universally agreed upon frame of reference for interstellar events", while true, is pedantic. We usually use the frame of reference of "Earth", because as long as we have to choose somewhere in space/time, it makes a lot of sense to choose "here-ish"*.

Now I can, of course, be modded "-1: explaining the joke".

*When/if we meet aliens or populate another planet, it may make more sense to start using a common reference frame in order to simplify the translations between coordinate systems. It is likely that that reference frame will be "the spot where the Big Bang occurred".

I Got To See This! (3, Insightful)

cusco (717999) | about 6 months ago | (#45888587)

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.

Re:I Got To See This! (1)

wonkey_monkey (2592601) | about 6 months ago | (#45888807)

Well, that's me jealous. It's been decades since I last saw even a decent comet.

I stayed out under that really amazing sky until I was shivering so badly from the cold that I couldn't hold my

:O

binoculars steady.

Whew.

Re:I Got To See This! (1)

cusco (717999) | about 6 months ago | (#45888947)

Well, if it's any consolation, I completely missed Haley's Comet. Was living in Seattle at that time, and the only cloudless nights I either had to work or ended up too stoned to drive anywhere out of the city lights.

Re:I Got To See This! (0)

Anonymous Coward | about 6 months ago | (#45890335)

You didn't miss much. A distant ship's smoke on the horizon. Hale-Bopp was much better.

So the movie was right? (1)

reboot246 (623534) | about 6 months ago | (#45890789)

There really is a Dust Factory - an old circus tent with a trapeze and a dirt floor? If I go there, will I get to meet my grandfather; fall in love with a cute blonde; and battle against an evil ringmaster? Let's go!

whoever this "unknown lamer" is, please fire him (1)

ihtoit (3393327) | about 6 months ago | (#45925689)

Before he arserapes any more submissions.

I put in the submission with ZERO inline links (why are there now FOUR?) no post commentary (UNNECESSARY) and no spelling or grammatical errors.

And for those who are overthinking this in terms of theoretical physics: go get a life, I was commenting on observed phenomena, not how fucking fast light was travelling in vacuo relative to the counterspin of charmed quarks - and there's your yardstick. 299792458m/s. Stick that in 168,000 years and there is your distance to event.

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