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Echoes from Ancient Supernovae Found?

Scientists at the Lawrence Livermore National Laboratory are claiming that they may have found echoes left over from ancient supernovae. From the article: "Just as a sound echo can occur when sound waves bounce off a distant surface and reflect back toward the listener, a light echo can be seen when light waves traveling through space are reflected back toward the viewer. The light echoes were discovered by comparing images of the Large Magellanic Cloud (LMC) taken years apart. By precisely subtracting the common elements in each image and analyzing what variable objects remain, the team looked for evidence of dark matter that might distort the light of stars in a transitory way, as part of a second-generation sky survey called SuperMACHO. SuperMACHO builds on the discoveries of the MACHO project, which started at Lawrence Livermore National Laboratory in 1989."

51 comments

  1. Echoes from Ancient Supernovae Found?? by Anonymous Coward · · Score: 2, Funny

    Supernovae ? Call the RIAA immediately !

    1. Re:Echoes from Ancient Supernovae Found?? by ceeam · · Score: 1

      That should be MPAA, you stupid first-poster! ;)

    2. Re:Echoes from Ancient Supernovae Found?? by TubeSteak · · Score: 3, Funny

      We called the MPAA at first, but they couldn't stand up to the massive quantities of hard radiation put out by supernovae.

      Unfortunately, the RIAA (being closely related to cockroaches) found themselves able to tolerate the radiation.

      I hear their mutated spawn plan on getting into the TV business.

      --
      [Fuck Beta]
      o0t!
    3. Re:Echoes from Ancient Supernovae Found?? by Ucklak · · Score: 1, Interesting

      "...as if millions of voices suddenly cried out in terror and were suddenly silenced."

      --
      if you steal from one source, that is plagiarism, if you steal from many, well, that's just research.
  2. Re:SuperMACHO? by Anonymous Coward · · Score: 0

    I'm sure you mean Bigus Dickus..

  3. Nothing new by FhnuZoag · · Score: 4, Informative

    The summary is a bit misleading. Light echoes are by no means a recent discovery. APOD viewers like me have seen them since at least 1997.

    http://antwrp.gsfc.nasa.gov/apod/ap971023.html

    1. Re:Nothing new by doubletruncation · · Score: 5, Informative

      This is actually a pretty exciting result that's different from the case of SN 1987A in that they're seeing light from ancient SN which were never observed originally. It's the idea of discovering ancient supernovae by light echoes that's new, not just seeing a light echo from a supernova. You can see their paper at http://xxx.lanl.gov/abs/astro-ph/0510738.

    2. Re:Nothing new by Megahurts · · Score: 1

      >Light echoes are by no means a recent discovery. APOD viewers
      >like me have seen them since at least 1997.


      I've see them pretty much every morning since the early 80's when I started combing my own hair.

  4. Its not a dupe! by vivek7006 · · Score: 2, Funny

    Without RTFA, I assumed that it is a dupe of http://slashdot.org/article.pl?sid=05/12/20/043218 &tid=95&tid=99

  5. "SuperMACHO" by CosmeticLobotamy · · Score: 4, Interesting

    It should be illegal to name your own project, especially with acronyms. Everything should be called "the thing we're doing" until someone unrelated comes along and names it. It would save so many horrible fake acronyms.

    1. Re:"SuperMACHO" by AndroidCat · · Score: 1
      They probably didn't create the MACHO acronym (MAssive Compact Halo Object) since it's been around for a while. A competing theory is WIMP (weakly interacting massive particles).

      Wheeee!

      --
      One line blog. I hear that they're called Twitters now.
    2. Re:"SuperMACHO" by FhnuZoag · · Score: 4, Informative

      But SuperMACHO is an awesome project name! You just need to know a bit of the background here.

      There are two main theories for Dark Matter (which, lest we forget, stands for missing mass that we can't seem to detect):

      1. WIMPs - Weakly Interacting Massive Particles. Stuff like neutrinos that interact only though gravity/weak nuclear. They are dark because they are so tiny and ghostly.
      2. MACHOs - MAssive Compact Halo Objects. Stuff like black holes, neutrons stars. Things so big and massive that they bend light around them and make themselves invisible, and of course emit no light themselves.

      Isn't it so neat that we have two natural acronyms here that stand in juxaposition to each other? Naturally, we call a project to find MACHOs, Project MACHO, and a project to supersede that Project SuperMACHO.

      See... Not horrible and fake at all.

    3. Re:"SuperMACHO" by CosmeticLobotamy · · Score: 2, Insightful

      MAssive Compact Halo Objects ... Isn't it so neat that we have two natural acronyms here

      A natural acronym would be MCHO (pronounced "mikko", or "macho" if you absolutely must), and MCHO would then be replaced by MCHO2.

      But I guess if they were going for the joke the first time around, it's not so bad.

    4. Re:"SuperMACHO" by Jedi+Alec · · Score: 2, Funny

      no matter what, both MACHO and WIMP are merely forms of Greatly Exagerrated Extra-terristrial Kaos.

      --

      People replying to my sig annoy me. That's why I change it all the time.
    5. Re:"SuperMACHO" by tnsimonson · · Score: 2, Funny

      Prior to being dubbed MACHO, the working title of this project was Compact Objects Juxtaposed Over Neglible Echo Systems, or COJONES. It was felt that this unfortunate acronym would be offensive to some, so the name was changed to Partially Uncovered Transient Anomalies Masked Against Dense Retrograde Echoes, or PUTA MADRE. Tragically, this acronym also caused anger in many circles, and thus was born MACHO.

      --
      -I like my women like I like my coffee - tied up in a sack and brought to me by Juan Valdez.
    6. Re:"SuperMACHO" by Dachannien · · Score: 1

      They were probably big Randy Savage fans, and wanted MACHO as a backronym.

      OH YEAH!!

  6. Re:Bonus Points! by Bros · · Score: 1, Informative

    "Super Novae" is the plural of "Super Nova".

  7. Re:Bonus Points! by Khuffie · · Score: 4, Interesting
    Hmm. I also thought it was weird, but according to google, both are correct.

    http://www.google.com/search?q=define:Supernovae
    http://www.google.com/search?q=define:Supernova

  8. what? by Anonymous Coward · · Score: 0

    Big Dyke isn't vulgar enough for you?

  9. Re:Bonus Points! by Khuffie · · Score: 1

    Nevermind. Seems like Super Novae is the plural ;)

  10. Re:Bonus Points! by giorgiofr · · Score: 4, Informative

    People should just stop trying to use latin plurals. First, they usually get them wrong (virii with two i's etc); second, once a foreign word becomes part of your language, you stop using its native plural, genitive if any, various cases etc.
    You don't go around saying you see a supernovam or the light of a supernovae, so why do you insist in saying there are two supernova (or novae if you get it wrong)? Either use always the same form of the word, or use English plural formation rules.

    --
    Global warming is a cube.
  11. Fascinating by Cally · · Score: 4, Interesting

    Well, this sounds really fascinating. I'm afraid I don't have much to add to that, so - on a slightly-related tangent - (the Magellanic Clouds) - the Opportunity Mars rover recently took pictures of the Martian sky at night that shows the Magellanic clouds. Check out the amateur image processing at Unmanned Spaceflight. There have been some amazing pics from the rovers, but this one stands out for me for emotional impact. (Mind you, I'm a sucker for schmaltz and sentiment... Boing Boing linked to a public domain radio version of "It's a Wonderful Life" the other day, I had to keep pausing it stop from bawling like a 5 year old :)

    --
    "None are more hopelessly enslaved than those who falsely believe they are free." -- Goethe
    1. Re:Fascinating by Anonymous Coward · · Score: 0

      While we're discussing related stuff, you should have a look at this article, which has a beautiful animation of light echoes from a suddenly brightening star (but not a supernova).

  12. Re:Bonus Points! by whig · · Score: 1

    Latin plurals get messed up a lot, but supernovae is the correct plural of (singular) supernova.

    --
    Peace and love, y'all
  13. Re:Bonus Points! by torako · · Score: 1

    One nova, many novae....

  14. What do you bet... by FlyByPC · · Score: 1

    ...that if they were designing one to observe Weakly-Interacting Massive Particles, that they wouldn't name it SuperWIMP?

    --
    Paleotechnologist and connoisseur of pretty shiny things.
  15. Re:Bonus Points! by giorgiofr · · Score: 1

    I don't agree: supernovum astrum -> supernova astra.

    --
    Global warming is a cube.
  16. Re:Bonus Points! by hoshino · · Score: 1

    On a seperate note, two i's or not, the plural of "virus" is "viruses" and nothing else.

  17. Re:Bonus Points! by Anonymous Coward · · Score: 0

    Ooh, the GWB school of thought, it's so hard... My childs were trying to sleep counting sheeps whilst wifes watering their cactuses suffered crisises wondering if mans and womans should clean their tooths as often as they clean their computer mouses.

  18. Re:Bonus Points! by giorgiofr · · Score: 1

    Self-reply: of course this invalidates the above examples (supernovam, etc.) and just goes to show how messy it becomes unless you set a standard.

    --
    Global warming is a cube.
  19. Wormhole? by QuantumInterference · · Score: 1

    The shortest distance between two points is a straight line... Would someone explain to me how light reflected by a 160,000 light year distant gas cloud reached Earth in less than 600 years?

  20. Slightly misspoken by localroger · · Score: 3, Informative

    What I'm sure the author meant to say is that the light from the original supernova explosion would have arrived here 600 years ago.

    --
    Brackets contain world's first nanosig, highly magnified:[.]
  21. Re:Bonus Points! by Anonymous Coward · · Score: 0

    But what is the plural of Elvis?

    Note: this is really only relevant in the vicinity of Las Vegas, NV

  22. supernova? by bmgz · · Score: 0

    I thought they were refering to incomplete torrents...

  23. Re:Bonus Points! by Anonymous Coward · · Score: 0

    cleared room

  24. Am I the only one excited about new torrents? ;) by legal_asshole · · Score: 0

    Bad state of affairs...

  25. Geeks by Craig+Ringer · · Score: 1

    This rule needs to go double for geeks. If the geek in question, or organization, has any history of committing the crime known as "the creation of a recursive acronym after 1985," the penalities for violation must be swift and extreme.

  26. Maybe you speak gaelic, by Inoshiro · · Score: 2, Funny

    but in my language, we use vowels!

    --
    --
    Internet Explorer (n): Another bug -- that is, a feature that can't be turned off -- in Windows.
  27. Re:Bonus Points! by blincoln · · Score: 1

    Insects have antennae. Spiders have chelicerae. I don't see what the problem is.

    --
    "...always new atoms but always doing the same dance, remembering what the dance was yesterday." -Richard Feynman
  28. APoD has had better light echoes by MillionthMonkey · · Score: 2, Interesting

    The significance of this particular story is that a thin, attenuated light echo was used to locate a supernova that is no longer visible. APOD has had far more spectacular light echoes but usually you can plainly see the primary source of the echo at the center since they are only a few years old. In this case the echoes they found were hundreds of years old- thin expanding rings of reflected light hundreds of light years in diameter- with centers that were completely dark. The echoes were only found serendipitously using digital image processing during a search for something else (dark matter).

    While it wasn't a supernova, the January 2002 flash from star V838 Monocerotis in the Milky Way made a nice, photogenic light-echo quite recently. The star, its flash, and the subsequent light echo are interesting for several reasons:

    1. The reason for the flash remains unexplained by theory, and the star has been posing problems for theorists ever since. Stars that make problems for theorists are always interesting.
    2. Although the flash was not a supernova, it made V838 Mon the brightest star in the entire Milky Way for a few days. The star's normal intensity was about 1 Sun, but at its peak the brightness was equivalent to 600,000 Suns. (For comparison, Rigel shines with the light of 40,000 Suns, and Deneb, one of the most powerful Milky Way stars known, shines with the light of up to 250,000.) But the flash was not a supernova (not bright enough) nor a nova since the star did not lose its outer envelope. The star swelled to a huge size (it would have reached the radius of Jupiter's orbit) and remained cooler at its surface than it had been before the flash.
    3. The star has a lot of interstellar dust surrounding it for light-years in every direction, which makes for good pictures as the light-echo from the flash widens and illuminates successive rings of dust around the star. (In any light-echo the rings are circular paraboloids, really, centered around the star-earth line, with the star at the focus of the paraboloid. The light echo you see is effectively reflecting off a huge "parabolic mirror" made of dust and pointing at you.)
    4. V838 Mon is in the Milky Way (only 20000 light years distant) so we can get better pictures of its light echo than the light echos associated with any recent supernovas. (The closest recent supernova was SN1987A and that was in the LMC, not the Milky Way.) People discovered this thing only a few days after it happened and we now have a sequence of very nice shots covering it at all times starting at the very beginning of the echo.

    V838 Mon has been featured on APOD eight times since 2002. Its light echo is now 8 years in diameter and is still vividly lighting up successive rings of crap in the vicinity of the star. There are many animations of the echo on the web but look for the more newer ones since they have more frames that include observations from 2004-2005.

    No widely accepted theory has succeeded in explaining the exact mechanism that caused the flash but astronomers generally agree that V838 Mon is a member of a new class of variable star that has been seen only twice before: M31-RV, a red variable in Andromeda that had a flash in 1989, and V4332 Sagittari, a red giant in Sagittarius that flashed in 1994. Current ideas include both cannibalism of a binary companion and planet swallowing.

    1. Re:APoD has had better light echoes by Markus+Registrada · · Score: 1
      1. The reason for the flash remains unexplained by theory, and the star has been posing problems for theorists ever since. Stars that make problems for theorists are always interesting.

      ...except when they're not.

      It appears that the distinction lies in whether the theorists think the star (a) appears to exemplify (some minor variation of) a widely popular but ill-supported theory, or (b) entirely contradicts a widely popular but ill-supported theory. It's easy to guess which one generates interest among theorists, but the result is flattering neither to theorists nor to astronomy's position as an actual science.

      An example of a star (or something) that causes problems for theorists, but is canonically uninteresting, is the high-z quasar (supposedly among the most distant and, perforce, luminous objects in the universe) physically in front of the nearby opaque galaxy NGC 7319. The silence since it was reported has been deafening.

    2. Re:APoD has had better light echoes by some+guy+I+know · · Score: 1
      The reason for the flash remains unexplained by theory
      Two words: Dyson Sphere.
      That's the reason that the star's temperature appears to be so low now, because what is actually being seen is waste heat emitted from the surface of the Dyson Sphere surrounding the star, and not anything from the star itself.
      The flash had something to do with the intial construction of the sphere, but I don't know what that is, because I'm not familiar enough with technology that advanced.

      Definitely a Dyson Sphere, though.
      Definitely.
      --
      Those who sacrifice security to condemn liberty deserve to repeat history or something. - Benjamin Santayana
    3. Re:APoD has had better light echoes by Xeriar · · Score: 1

      An example of a star (or something) that causes problems for theorists, but is canonically uninteresting, is the high-z quasar (supposedly among the most distant and, perforce, luminous objects in the universe) physically in front of the nearby opaque galaxy NGC 7319. The silence since it was reported has been deafening

      It's been noticed, but it is rather weak.

      It could be a really damn bright quasar, or it could be from a collision that sent a black hole careening away at extreme velocities. Either way, more data is needed and there are many, easier to picture-with-current-tech mysteries clamoring for it.

  29. Look for Nova from Christ's birth? by ZoomieDood · · Score: 1

    Well, the subject kinda says it all.

    Which way is east again?

  30. Wait a minute.. by Alpha_Traveller · · Score: 1

    ::::Wipewipewipewipe::::

    Sorry, I sneezed on the receiver, take the picture of the galaxy again and tell me what you see in comparison....

    --
    "Love is like pi - natural, irrational, and very important." (Lisa Hoffman)
  31. Comment removed by account_deleted · · Score: 1

    Comment removed based on user account deletion