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Big Mystery in Astronomy - Radio bursts

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    Big Mystery in Astronomy - Radio bursts

    Here's a big mystery in astronomy: fast radio bursts. Brief shrieks of radio waves coming from space.
    What are they? Where do they come from?
    Astronomers have no idea.

    You might think you’re watching an educational channel, where I explain fascinating concepts in space and astronomy, but that’s not really what’s going on here.

    What’s actually happening is that you’re tagging along as I learn more and more about new and cool things happening in the Universe. I dig into them like a badger hiding a cow carcass, and we all get to enjoy the cache of knowledge I uncover.

    Okay, that analogy got a little weird. Anyway, my point is. Squirrel!

    Fast radio bursts are the new cosmic whatzits confusing and baffling astronomers, and now we get to take a front seat and watch them move through all stages of process of discovery.

    Stage 1: A strange new anomaly is discovered that doesn’t fit any current model of the cosmos. For example, strange Boyajian’s Star. You know, that star that probably doesn’t have an alien megastructure orbiting around it, but astronomers can’t rule that out just yet?

    Stage 2: Astronomers struggle to find other examples of this thing. They pitch ideas for new missions and scientific instruments. No idea is too crazy, until it’s proven to be too crazy. Examples include dark matter, dark energy, and that idea that we’re living in a

    Stage 3: Astronomers develop a model for the thing, find evidence that matches their predictions, and vast majority of the astronomical community comes to a consensus on what this thing is. Like quasars and gamma ray bursts. YouTuber’s make their videos. Textbooks are updated. Balance is restored.

    Today we’re going to talk about Fast Radio Bursts. They just moved from Stage 1 to Stage 2. Let’s dig in.

    Fast radio bursts, or FRBs, or “Furbys” were first detected in 2007 by the astronomer Duncan Lorimer from West Virginia University.

    He was looking through an archive of pulsar observations. Pulsars, of course, are newly formed neutron stars, the remnants left over from supernova explosions. They spin rapidly, blasting out twin beams of radiation. Some can spin hundreds of times a second, so precisely you could set your watch to them.

    In this data, Lorimer made a “that’s funny” observation, when he noticed one blast of radio waves that squealed for 5 milliseconds and then it was gone. It didn’t match any other observation or prediction of what should be out there, so astronomers set out to find more of them.

    Over the last 10 years, astronomers have found about 25 more examples of Fast Radio Bursts. Each one only lasts a few milliseconds, and then fades away forever. A one time event that can appear anywhere in the sky and only last for a couple milliseconds and never repeats is not an astronomer’s favorite target of study.

    Actually, one FRB has been found to repeat, maybe.

    The question, of course, is “what are they?”. And the answer, right now is, “astronomers have no idea.”

    In fact, until very recently, astronomers weren’t ever certain they were coming from space at all. We’re surrounded by radio signals all the time, so a terrestrial source of fast radio bursts seems totally logical.

    About a week ago, astronomers from Australia announced that FRBs are definitely coming from outside the Earth. They used the Molonglo Observatory Synthesis Telescope (or MOST) in Canberra to gather data on a large patch of sky.

    Then they sifted through 1,000 terabytes of data and found just 3 fast radio bursts.

    Three.

    Since MOST is farsighted and can’t perceive any radio signals closer than 10,000 km away, the signals had to be coming outside planet Earth. They were “extraterrestrial” in origin.

    Right now, fast radio bursts are infuriating to astronomers. They don’t seem to match up with any other events we can see. They’re not the afterglow of a supernova, or tied in some way to gamma ray bursts.

    In order to really figure out what’s going on, astronomers need new tools, and there’s a perfect instrument coming. Astronomers are building a new telescope called the Canadian Hydrogen Intensity Mapping Experiment (or CHIME), which is under construction near the town of Penticton in my own British Columbia.

    73 Al 4L5A
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