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Earth Space Science

Earth-Sized Telescope Set To Snap First Picture of a Black Hole (newscientist.com) 103

An anonymous reader writes from a New Scientist report: This week, we will have our first chance to take a picture of the supermassive black hole at the centre of our galaxy. The image could teach us how black holes work and even how the largest and smallest forces governing the universe fit together. The Event Horizon Telescope is switching on. It consists of eight radio observatories around the world, including telescopes in Spain, the US and Antarctica. And for just four or five nights between 5 and 14 April, if the weather is clear at all of the observatories, they will all turn on at once. Each telescope will point at Sagittarius A, the supermassive black hole at the centre of the Milky Way, and measure every radio wave coming from its direction. Linking together observatories spread across such a huge area and combining their observations to filter out extra light will effectively create a powerful "virtual telescope" almost the size of Earth. These telescopes will together capture sharper and more detailed data than we've ever had from Sagittarius A, which we still know very little about, as well as the larger black hole at the centre of nearby galaxy M87. With the telescopes generating a total of 2 petabytes of data per night -- enough to store the full genomes of some 2 billion people -- astronomers hope to take the first image of the event horizon around a black hole, and the bright matter hurtling around it.
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Earth-Sized Telescope Set To Snap First Picture of a Black Hole

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  • by Anonymous Coward

    Says, what's up doc?

    https://www.youtube.com/watch?... [youtube.com]

  • units (Score:2, Interesting)

    by ooloorie ( 4394035 )

    enough to store the full genomes of some 2 billion people

    I have trouble with this "full genome" unit. Can you please express that in "football fields"?

    OK, if you must, let's express that in metric units: it's about 1.6 x 10^-9 moles, or 1.6 nanomoles, of bytes.

  • Linking together observatories spread across such a huge area...

    It is a symptom of humanity's hubris to believe that an area the size of Earth is considered huge when measuring the massive black hole that sits at the center of our galaxy.

    • hubris to believe that an area the size of Earth is considered huge

      I think it would be considered huge compared to other radio telescopes, though.

    • by ScentCone ( 795499 ) on Friday April 07, 2017 @09:53AM (#54191375)

      It is a symptom of humanity's hubris to believe that an area the size of Earth is considered huge when measuring the massive black hole that sits at the center of our galaxy.

      But what is it a symptom of when somebody complaining about that description completely fails to understand that the description compares the array to the size of a traditional, single observatory or an array located in one area ... and was not a comparison to the intended observational target? It's not "hubris." It's ... what? "Totally missing the point, but not missing the opportunity to sound a bit patronizing anyway?"

      • I am really curious about this - if I place a satellite dish in California and one in New York, do I know have a receiver as large as the Untied States?
        • by Anonymous Coward

          You only get the *brightness* of two small receivers.
          But you get the *sharpness* of an absurdly large receiver.

    • It's huge because we used to have ~10 km sized baselines or so even when interferometry was used.
      • by Anonymous Coward

        Why not build a couple of telescopes in space? Put them in orbits on opposite sides of the sun. Then you have a nice baseline for interferometry.

        • You don't even need the heliocentric orbit, just getting stuff to the Moon would be a fifty-fold improvement in our current capability. Or simply somewhere in the cislunar space.
    • You do realise that a black hole of any size is a singularity right? i.e. it is smaller than the earth.

      • by Anonymous Coward

        You do realise that a black hole of any size is a singularity right? i.e. it is smaller than the earth.

        Yes...pedantic perhaps, but I cannot stop myself: That would depend on what exactly you mean by the 'size' of a black hole. I think generally when referring to a black hole's size, people refer to the event horizon - ie the 'black' part of the black hole. Which for Sagittarius A is estimated to be 17 times the radius of the Sun. So, pretty big.

        https://en.wikipedia.org/wiki/Sagittarius_A*#Central_black_hole

        • Even so, the premise of the stupid comment above is that its hubris to consider a telescope the size of the earth as a big telescope. But I can see the sun with no telescope at all, probably even from the centre of the milky way. So the idea that a telescope the size of the earth is not "big" when trying to look at an object that is 17x *BIGGER* than the sun, is kind of idiotic, no? I mean, I don't know all the calculations, but it strikes me as stupid.

    • It is a symptom of humanity's hubris to believe that an area the size of Earth is considered huge when measuring the massive black hole that sits at the center of our galaxy.

      It is a symptom of humanity's hubris to believe that the black hole in our galaxy is considered massive.

    • Linking together observatories spread across such a huge area...

      It is a symptom of humanity's hubris to believe that an area the size of Earth is considered huge when measuring the massive black hole that sits at the center of our galaxy.

      You sound like Clark from Good Will Hunting, spouting off seemingly highbrow garbage in an attempt to sound intelligent but ultimately just coming off as a douche. There is nothing hubris about the passage and you completely misunderstood and misinterpreted the same by trying to belittle it (and all of us in the process).

  • by macxcool ( 1370409 ) on Friday April 07, 2017 @09:49AM (#54191347)

    enough to store the full genomes of some 2 billion people

    There's a useless comparison. Unless you're doing a lot of genome storage I'd think that you'd have no idea what that means.

    • by Anonymous Coward

      Especially since 99.9-something percent of those genomes are going to be identical each other. You could run some awesome de-dupe compression on that.

    • At least I can understand a unit like libraries of congress*, but what the hell does a genome look like?

      *Note I have never been to the library of congress, only seen pictures so don't use those shitty units either.

  • by Geoffrey.landis ( 926948 ) on Friday April 07, 2017 @10:05AM (#54191451) Homepage

    You can't, of course, "see" a black hole, even with radio waves: a black hole is by definition what you can't see.(*)

    What they are looking to image is the radio emissions from material falling into the black hole. You can't see the black hole itself.
    --
    *footnote: Black holes do emit Hawking radiation, which in principle is detectable. But the peculiar property of Hawking radiation is that the smaller the black hole the more Hawking radiation. Only exceptionally tiny black holes emit enough to possibly detect-- a black hole ten micro meters across will emit just about the same amount of Hawking radiation as the microwave background.

    • Well then by the same logic you can't really see matter either. All you see is reflected photons.
    • by sconeu ( 64226 )
      Sure you can. I have the negatives of the photo right here!

      ---- BEGIN NEGATIVE ----

      ---- END NEGATIVE ----

    • "Well, the thing about a black hole - its main distinguishing feature - is it's black. And the thing about space, the colour of space, your basic space colour, is black. So how are you supposed to see them?" - Holly, System AI, Jupiter Mining Corp. vessel Red Dwarf
  • We are about to look at something you can't see?

  • by wisebabo ( 638845 ) on Friday April 07, 2017 @10:32AM (#54191627) Journal

    So, why do RADIO telescopes need to be concerned about the weather? I mean they look in the radio part of the spectrum and I would assume at the frequencies that aren't that affected by water vapor (or atmospheric gasses). So turbulence in the atmosphere wouldn't affect their performance (other than perhaps shaking the dish).

    Is it because they are referring to electrical storms (lightning)? Or perhaps they are referring to "space" weather like solar flares and the ionosphere? (But I've never heard of those being an impediment to radio astronomy).

    Anyway, just asking

  • by Anonymous Coward

    It's Sagittarius A*, pronounced Sagittarius A-star.

  • You don't have to dumb it down and say "virtual telescope". Call it what it is - an interferometer [wikipedia.org] and make it a link so people who don't know the term can read about it and educate themselves.
  • ... At least I now know one person's genome information is 1TB

    ...which is genuinely interesting to me (though not relevant to the topic at hand).

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