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Space Science

'What's Up With Betelgeuse?' (steamboatpilot.com) 47

"Last month, astronomers noticed Betelgeuse had faded much more than usual," writes the Steamboat Pilot & Today. "This is the faintest it has been in over a century of observations.

"What's up with Betelgeuse?"

The Grim Reefer quotes their report:
Well, probably nothing. It is most likely experiencing a super minimum as two of its variability cycles sync up and reach minimum brightness at the same time. On the other hand, stars like Betelgeuse are well advanced in age and are destined to explode as supernovas at the end of their lives.

There hasn't been a bright supernova in our Milky Way galaxy since the supernova of 1604. Sure, we've seen supernovas in galaxies far, far away, but none have been seen close to home. So, there is some excitement in the astronomical community, warranted or not, that Betelgeuse might be ready to pop. Astrophysicists theorize that a pronounced fading might presage an impending supernova explosion. If Betelgeuse continues to fade into January and beyond, then look out -- the end might be near.

A Forbes science writer remains skeptical, but points out that "some astronomers now think there's a much closer star that could 'nova'..."
A star called V Sagittae, 7,800 light years distant in the tiny constellation of Sagitta (just below Cygnus in the famous "Summer Triangle" asterism of stars) is barely visible even in mid-sized telescopes, but new research suggests that it could explode around the year 2083... "Around the year 2083, its accretion rate will rise catastrophically, spilling mass at incredibly high rates onto the white dwarf, with this material blazing away," says Professor Emeritus Bradley E. Schaefer, LSU Department of Physics & Astronomy. "In the final days of this death-spiral, all of the mass from the companion star will fall onto the white dwarf, creating a super-massive wind from the merging star, appearing as bright as Sirius, possibly even as bright as Venus."

The uncertainty of the prediction is plus or minus 16 years, so it could happen between 2067 and 2099, most likely near the middle of this range. It promises to be a wonderful sight.

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'What's Up With Betelgeuse?'

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  • by Tim Hamilton ( 5961502 ) on Sunday January 19, 2020 @11:36AM (#59634770)
    Ah. Well... I attended Juilliard... I'm a graduate of the Harvard business school. I travel quite extensively. I lived through the Black Plague and had a pretty good time during that. I've seen the EXORCIST ABOUT A HUNDRED AND SIXTY-SEVEN TIMES, AND IT KEEPS GETTING FUNNIER EVERY SINGLE TIME I SEE IT... NOT TO MENTION THE FACT THAT YOU'RE TALKING TO A DEAD GUY... NOW WHAT DO YOU THINK?!?!?!?!? You think I'm qualified?
  • by war4peace ( 1628283 ) on Sunday January 19, 2020 @11:38AM (#59634774)

    I'll be 104 in 2083. Looking forward to seeing the Nova :)
    Joke aside, what's with the "a much closer star" thing? Betelgeuse is cca 700LY away, while V Sagittae is 7,800 LY away.

    • by thomst ( 1640045 )

      war4peace confessed:

      I'll be 104 in 2083. Looking forward to seeing the Nova :)

      ITIYM "Supernova."

      It's the white dwarf star in the V Sagittae binary system that's going to go boom, not its big companion. That means the event will be a Type Ia supernova (aka: a "standard candle"), which always happens when a white dwarf steals exactly enough of a large companion's atmosphere to reach Chandrasekhar's Limit (the amount of mass it takes to trigger a supernova). If you know the rate of accretion, and can determine the current mass of the white dwarf member of the binary

      • by ceoyoyo ( 59147 )

        Nope. The Forbes science writer doesn't seem all that sure about any of the science so I was unclear whether he said "nova" on purpose or not. Turns out he did accurately report whatever he was told. V Sagittae is a small white dwarf orbiting a larger main sequence star. The system is a weird cataclysmic variable and is expected to continue brightening until the two stars merge to form a red dwarf.

        It will nova, or create a "merge burst" as described by the astronomers who studied it, not a supernova.

        • the two stars merge to form a red dwarf.

          So a white dwarf will merge with a larger star to form a red dwarf?

          I don't think so. Stars don't work that way.

          • Fact is, we don't know how stars work. It's all theory.
            On top of that, we don't actually know what causes a super nova either. That's all theory too.
            So, give it a few years, and the scientists will be just as perplexed when Betelgeuse brightens up again.
            Someone will say it's at the end of a super-cycle for sun spots or something, and it will all blow over - but in the end, that's just another theory.
            They won't explain whyt it's the end of the super-cycle for sun spots, and they won't explain where all the

          • by ceoyoyo ( 59147 )

            Damn, it's too bad you didn't post that at the beginning of the month. You would have been in time to get down to the AAS meeting in Hawai'i and present your refutation. Catchy name for an abstract: "Stars Don't Work That Way", ShanghaiBill, Slashdot

            Abstract #435.04
            https://aas.org/sites/default/... [aas.org]

          • Comment removed based on user account deletion
    • Nova or Supernova?

      Supernova in 700LY is actually dangerously close. The "kill radius" is estimated to be ~ 50-100LY. At 700 LY that will still be a very significant increase in X and Gamma rays.

      You do not want to be that close to fireworks of that magnitude.

      • Now you know how the X Men came about...
      • Nova or Supernova?

        Supernova in 700LY is actually dangerously close. The "kill radius" is estimated to be ~ 50-100LY. At 700 LY that will still be a very significant increase in X and Gamma rays..

        The "kill radius" (genuinely dangerous effects) is more like 25 LY, 50 LY would have significant but not catastrophic effects. At 700 LY, where the effects are reduced to 0.12% of the 25 LY case it is actually NOT IN ANY WAY "dangerously" close.

  • by 110010001000 ( 697113 ) on Sunday January 19, 2020 @11:41AM (#59634780) Homepage Journal

    "Last month, astronomers noticed Betelgeuse had faded much more than usual," writes the Steamboat Pilot & Today"
     
    I'm intrigued by the first sentence already.

    • by hey! ( 33014 )

      Getting your science news from a free tabloid is no weirder than getting it through Facebook.

      In the post-Sputnik era there was science journalism all over the place; major newspapers all had a science desk that covered breaking news and put out regular weekly science sections. Today most people get their science information filtered through PR offices and marketing campaigns. Think Dr. Oz. There's really only one source that still does science journalism on a big scale that I know about: Science News [sciencenews.org]. Ev

  • “Much closer” (Score:5, Informative)

    by cnaumann ( 466328 ) on Sunday January 19, 2020 @11:42AM (#59634784)

    Much closer to nova maybe, not closer to earth. Betelgeuse is only 650 light years from earth. It was the first star (other than the sun) that was resolved as a disc.

  • What's up? (Score:2, Funny)

    by Anonymous Coward

    The article has been posted 3 times and now we're fucked.

  • Is it just a coincidence that unexpected gravity waves have also been detected in the same region?

    https://science.slashdot.org/s... [slashdot.org]

  • I could happen then? Or we could see it then, meaning it actually happened centuries ago. The speed of light is fast but not instantaneous.
    • by ceoyoyo ( 59147 )

      Any time between later today and a few hundred thousand years from now.

    • The speed of light in a vacuum is instantaneous in relative terms, that's why it's the fastest possible speed and FTL travel is incoherent. From the point of view of the light if it were sentient, which is just as valid a point of view as ours, the light can cross the galaxy instantly.

      Saying that things we perceive now happened X years ago because they're X light years away is a failure to understand that space and time are linked, not separate. The universe cannot have a singular present time at all places

      • Except it really did already go nova by now because it's a bit over 700 lightyears away - it takes that long for the light showing it went nova to reach us.
        • You don't appear to have made any attempt to understand, so I'll simplify it. It is now the year 1320 AD at that location 1700 ly away. The extent to which that statement is nonsensical is simply the extent to which the concept of a singular "now" is nonsensical at that distance.

  • by kbahey ( 102895 ) on Sunday January 19, 2020 @12:55PM (#59634972) Homepage

    This topic was discussed a few days ago, and duplicates are the new norm on Slashdot these days. Granted there is an additional part on V Sagittae this time.

    Anyway, I explained here [slashdot.org] that there are three components to the light curve:

    - a 180 day cycle
    - a 425 day one
    - a 5.9 years

    It just so happens that "the current faintness of Betelgeuse appears to arise from the coincidence of the star being near the minimum light of the ~5.9-yr light-cycle as well as near, the deeper than usual, minimum of the ~425-d period.".

    So two minima overlapped, and we get Betelgeuse fainter than any time in recorded history.

    See this Astronomical Telegram [astronomerstelegram.org], and the light curve from AAVSO [skyandtelescope.com].

    As for the V Sagittae, I will not be alive then. But I showed the info to my youngest daughter (who may be alive then), to reminisce about me telling her about this event, if she ever sees it.

    • by sferics ( 189924 )

      Thanks. I missed this info the first time around, so I guess there's something to be said for duplicates.

      Out of my shallow understanding of stellar physics, Betelgeuse strikes me as one hell of a dumpster fire.

  • This is the event that causes Ford Prefect to hitch a ride to Earth.
  • by Roger W Moore ( 538166 ) on Sunday January 19, 2020 @02:27PM (#59635196) Journal

    Sure, we've seen supernovas in galaxies far, far away, but none have been seen close to home.

    Not as close as Betelgeuse but SN1987A was seen 168klyrs away in the Large Magellanic Cloud which is a satellite galaxy of the Milky Way and, if it even counts as a separate galaxy, then it would be the closest galaxy to the Milky Way: the exact opposite of "a galaxy far, far away"! It was close enough that so far it has been the only Super Nova ever observed with neutrinos as well as light.

  • They should have had Michael Keaton reprise his role as Beetlejuice Vs. the Ghostbusters. NBC and Sony that own these properties would have to share the resulting profits.

    • by Quirkz ( 1206400 )

      You know, if they can get away with Alien vs. Predator, they could probably pull this off, too.

  • by Forty Two Tenfold ( 1134125 ) on Sunday January 19, 2020 @02:53PM (#59635296)
    No.
  • Comment removed based on user account deletion
  • So, starts by discussing Betelgeuse, then then refers to V Sagittae by saying:

    A Forbes science writer remains skeptical, but points out that "some astronomers now think there's a much closer star that could 'nova'..."

    Betelgeuse is ~700 ly from us while V Sagittae is ~7800 ly from us. That's not even math, that's reading comprehension. Me thinks Forbes needs a new science writer.

  • I hope that Ix has made his getaway by now, since it might be too late otherwise.

  • I sense a deep tremor in the Force.

  • Maybe we're just witnessing the after effects of its invention?

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