2886: Fast Radio Bursts

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Fast Radio Bursts
Dr Petroff has also shown that the Higgs boson signal was actually sparks from someone microwaving grapes, the EHT black hole photo was a frozen bagel someone left in too long, and the LIGO detection was just someone slamming the microwave door too hard.
Title text: Dr Petroff has also shown that the Higgs boson signal was actually sparks from someone microwaving grapes, the EHT black hole photo was a frozen bagel someone left in too long, and the LIGO detection was just someone slamming the microwave door too hard.


Cueball is giving a presentation, stating the different sources of fast radio bursts, which are short high-energy signals which have been detected by astronomers, but whose sources are not known. His team is pretty sure that most of these bursts are energetic stellar objects in space - that is, astronomical phenomena.

He then says that some of them are caused by microwave ovens, citing Dr. Emily Petroff's work on identifying the apparent source of "perytons" at the Parkes Observatory.[1] These are signals similar to fast radio bursts, but which originate on Earth and not in space; initial hypotheses included atmospheric effects related to lightning and passing aircraft, but they were eventually identified as a much closer range signal from microwaves escaping as the oven door was opened inside the observatory.

After that, he explores two further options, combining attributes of the previous two:

  • Energetic stellar-sized microwave ovens floating in space; this is unlikely since microwave ovens typically are not stellar-sized and all known microwave ovens originate on Earth rather than in space. (There is a microwave oven installed in the Chinese Tiangong space station, but it appears that the ISS is less well equipped than that. Neither facility is ever likely to have room for 'stellar-sized' equipment of any kind.)
  • An energetic stellar-sized object in the observatory break room would be surprising, as we have yet to see a break room large enough to contain a stellar-sized object. Although unlikely, he says he sends a grad student there to double-check. Presumably, the student is being sent rather than Cueball himself both because it is unlikely to give useful data, and because if there is indeed energetic stellar plasma in the break room, the million-degree temperatures would probably kill anyone who enters it, and grad students are disposable when compared to researchers.

Note that, as well as the universe-sized Cosmic microwave background radiation, there are various microwave-bright Pulsars and other strong microwave signals originating from actual stars, but no reason to believe that they are deliberately purposed/engineered as any actual oven, despite misleading language sometimes employed by those in the field.

The title text references several other discoveries, with Dr. Petroff suggesting explanations based on microwave ovens for each of them, as was the case with her discovery:

  • The apparent detection of the Higgs boson at the Large Hadron Collider was actually someone microwaving grapes, which generates plasma
  • The image of a black hole captured by the Event Horizon Telescope was a burning bagel (a notably ring-shaped bread product with the charred portion being black)
  • LIGO (the Laser Interferometer Gravitational-Wave Observatory) did not detect gravitational waves, but was instead disturbed by someone slamming the microwave door too hard

In each case, these are highly improbable - for instance, LIGO used a complex suspension system, and two sites (one in Louisiana and one in Washington State) comparing signals, to rule out such interference. The real Dr. Petroff has not made any such claims.[citation needed]

See 2289: Scenario 4 for a similar situation.


  1. E.Petroff et al. (2015). "Identifying the source of perytons at the Parkes radio telescope". Monthly Notices of the Royal Astronomical Society, 451(4):3933–3940.


Ambox notice.png This transcript is incomplete. Please help editing it! Thanks.
[Cueball standing behind a lectern, with a poster hung from the ceiling behind him, raising his hand]
Potential sources of fast radio bursts:
(1) Energetic stellar-sized astrophysical objects floating in space
Cueball: We're pretty sure this is what most of them are.
[Close-up on Cueball, not raising hand.]
(2) Microwave ovens in the observatory break room
Cueball: This was some of them, oops. (Petroff et. al., 2015)
(3) Energetic steller-sized microwave ovens floating in space
Cueball: We think this one is unlikely.
[Zoom out back to perspective of first panel.]
(4) Energetic stellar-sized astrophysical objects in the observatory break room
Cueball: This is almost certainly not it, though we're sending a grad student to double-check.

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(2) microwave ovens in the observation break room: https://arxiv.org/pdf/1504.02165v1.pdf

You forgot to sign :)
The detection of radiation from the tower microwave would be very surprising as the tower is shielded on the windows and in the walls and the dish surface blocks the line of sight to the receiver in the cabin at the prime focus. However it was later determined that the Woolshed microwave was also in use at the time, unrelated to these tests, and might potentially have been the source of the peryton. 04:57, 27 January 2024 (UTC)

Clearly, one of the LIGO observations was a real gravitational wave while the other was just the microwave door slamming ;) Solomon (talk) 07:01, 27 January 2024 (UTC)

I like that the comic is both a story in four pictures and a 2x2 grid of combinations. -- 07:52, 27 January 2024 (UTC)

the grad student inside joke - emily petroff did not get her phd until november 2015, the paper was published in april 2015, so the "grad student" figured it out. check out her graph: https://imgur.com/NBJOkyB (via: https://www.iflscience.com/astronomical-quest-leads-ovens-27839 )

The microwaving grapes/plasma phenomenon was previously referenced in the What If post on microwaving frozen food. The black hole/bagel may well be a reference to the film Everything Everywhere All At Once, where a character put “everything” (in the multiverse) on a bagel and created a devouring vortex. —-

I liked Michael Lynch's comment on the XKCD Facebook page - "We tried removing the microwave however when we did that, no researchers were willing to spend enough time at the observatory to take any observations." - how true. (talk) 19:14, 29 January 2024 (please sign your comments with ~~~~)

We traced the FRB. It's coming from inside the observatory! 20:54, 29 January 2024 (UTC)

I'm wondering if we need a citation for the statement "Energetic stellar-sized microwave ovens; this is unlikely since microwaves typically are not stellar-sized and all known microwave ovens originate on Earth rather than in space."... Probably just one of those "citation needed" (with link to 285) superscript thing that I don't know how to add. But also, what proof do we have that there are no stellar-sized microwave ovens, either human-made or otherwise? And what are the odds that the grad student was sent to a break room that contains one of those? CaTastrophy427 (talk) 21:00, 29 January 2024 (UTC)

Well, to answer your "how you do it", the template is {{Citation needed}}. There are other templates/redirecting templates, {{cn}}, {{citation needed}}, {{Citation Needed}}, {{fact}}, etc, and an {{Actual citation needed}}/etc for the more non-joke version, but the first one is the prime one). Now you know, do use it if you think you need to. (But no need to overuse it.)
There is, however, a linked citation about the one noted microwave oven in space (which came originated from Earth, an almost undeniable fact I think you'd have a hard time ignoring...) and various microwave sources in space (some stellar-sized - maybe you could argue the 'citationable' status of none of them being ovens).
In my head, if there's a link that covers any reasonable amount of the 'doubt' about a fact then it tends to make the "Citation needed" joke not really as funny as it might have been. (And removing useful links to bring the CN back into usefulness is retrograde as far as explaining.) So think hard about it. Editors who disagree (either way) are inclined to edit out (or in) these things as they see fit. You have the power, but so does everyone else, ok? 21:42, 29 January 2024 (UTC)

Grad students are the redshirts of scientific research. Psychoticpotato (talk) 21:28, 6 May 2024 (UTC)