BIG badaboom
November 21, 2019 9:11 AM   Subscribe

So, two massive stars a significant fraction of the way across the observable Universe exploded, blasting out death rays into space so energetic that when they reached Earth they created faster-than-light shock waves in our atmosphere.
Phil "Bad Astronomer" Plait writes about two newly observed Gamma Ray Bursts and how incredibly powerful they were.

(If, unlike me, you understand why these shock waves could travel faster than light without breaking the laws of physics without having had to read the article, you deserve a no-prize.)

Make sure to check out the Twitter thread too.
posted by MartinWisse (13 comments total) 22 users marked this as a favorite
 
To answer everyone's first question from the tweet, that's "faster than the speed of light in our atmosphere", not faster than light in a vacuum. This is the whole Cerenkov radiation phenomenon.
posted by rum-soaked space hobo at 9:25 AM on November 21, 2019 [12 favorites]


I'm still in awe that these blasts happened 6 and 4.5 billion light years away and we saw them. Meaning the visible travel took 6 and 4.5 billion years (or more, since ya know, light speed limits) to reach our planet. These blasts happened while the earth was a molten goo ball and it had the time to harden, evolve dinosaurs, kill them off, evolve us, let us build massive (64 tons) telescopes, and coordinate them to spin and catch these as they reached us.
posted by msbutah at 9:46 AM on November 21, 2019 [11 favorites]


Woot! I helped launch Swift 15 years ago yesterday, and I flew Fermi after that. Here's to many more years of observations of GRBs!
posted by Rob Rockets at 10:20 AM on November 21, 2019 [33 favorites]


The Gizmondo article about this had:

"...a “typical burst releases as much energy in a few seconds as the Sun will in its
entire 10-billion-year lifetime,” explained astronomer Gemma Anderson, a
study co-author from the Curtin University node of the International
Centre for Radio Astronomy Research, in a press release."
posted by aleph at 11:34 AM on November 21, 2019 [3 favorites]


Any news if Icecube detected a related event?
posted by mbo at 11:37 AM on November 21, 2019 [1 favorite]


> Here's to many more years of observations of GRBs!

Distant and indirect bursts, ideally.
posted by Godspeed.You!Black.Emperor.Penguin at 1:17 PM on November 21, 2019 [9 favorites]


The same giz article mentioned also said one of the Earth's "extinction events" matched the pattern of a Gamma Ray Burst.

"“There is one mass extinction event that we can see in the geological
record—the Ordovician extinction—which matches with what we’d expect
from a gamma-ray burst,” Levan said. “If an event went off close enough
to the Earth to affect us now, we’d have some somewhat paradoxical effects.”

First, the ozone layer would be destroyed by the gamma-rays, allowing
copious amounts of UV light to reach the surface, said Levan. Visible
light, by contrast, would likely be blocked due to the destruction of
key molecules in the atmosphere and the presence of nitrous oxides,
which would block sunlight, triggering an ice age. This double-whammy of
atmospheric effects would be... bad.

“This is consistent with what was seen 440 million years ago during the
Ordovician extinction, though it isn’t the only possible explanation,”
posted by aleph at 2:04 PM on November 21, 2019 [3 favorites]


Came to compliment the post title. Stayed for the article. Left knowing that Rob Rockets literally does. Mefi always over-delivers!
posted by booksarelame at 2:58 PM on November 21, 2019 [6 favorites]


Also energetic: the Oh-My-God particle.
posted by Wet Spot at 5:05 PM on November 21, 2019


This is still like a little baby compared to the merger of black holes, which can unleash more power than every star in the observable universe combined for some milliseconds, though it's gravity waves rather than photons.
posted by save alive nothing that breatheth at 8:29 PM on November 21, 2019 [1 favorite]


Much more details: NASA link
posted by aleph at 9:23 AM on November 22, 2019


So reading that this GRB originated halfway across the universe led me to wonder what the furthest observations we've made are. It turns out that honour belongs to another GRB numbered 090423 which occurred some thirteen billion light years away, when the universe was just a little baby universe. And that led me to learn about the star HD 140283 (a.k.a. the "Methuselah Star") which wikipedia helpfully informed me was older than the universe itself.

Even to this layman, that's obviously not possible. This comment at Stack Exchange suggests that the reason for the confusion lies in the uncertainty of the estimates, so I have quietly corrected that particular oversight.

I think what I'm trying to say is I'm pretty much an astrophysicist now.
posted by Acey at 11:10 AM on November 22, 2019 [2 favorites]


Holy crap HD 140283 is only 200 light years away rather than at the edge of the observable universe. The reason we know it's so old is because it is so close (and therefor distance measurable by parallax) but still pretty amazing to me.
posted by Mitheral at 12:07 AM on November 23, 2019 [1 favorite]


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