4 ms·

A Brilliant and Nearby One-off Fast Radio Burst Localized to 13 pc Precision

95 points by gnabgib 1y ago

addaon 1y ago
Is kJy as a brightness unit the abomination I think it is?
- bqmjjx0kac 1y ago
  You nerd sniped me :) In this context, I believe it is a kilo-Jansky, not a kilo-Joule * year. https://en.wikipedia.org/wiki/Jansky https://en.wikipedia.org/wiki/Jansky
  - dotancohen 1y ago
    I don't think that replacing two ill fitting but probable units with a single obscure unit is much of an improvement!
    - 8bitsrule 1y ago
      It appears to have something to do with CGS units. 1 Jy = 10-23 erg s-1 cm-2 Hz-1 (cgs) only their figure: L9.9 GHz < 2.1 × 10^25 erg s−1 Hz−1 leaves out the cm-2. (So not a density, like Jy. Perhaps 'L' is luminosity? ... As in: "The solar luminosity unit is a measure of the Sun's radiant energy and is equal to 3.828×10^(26) Watts." -(NRAO) While groping, I found this helpful page called Brightness in Radio Astronomy: http://physics.wku.edu/~gibson/radio/brightness.html http://physics.wku.edu/~gibson/radio/brightness.html
      - dotancohen 1y ago
        I was thinking maybe joules/year e.g. energy/time might be some brightness indicator for some astronomical definition of brightness - especially in the non-optical wavelengths. But that's division, not multiplication. Another thread in my brain thought maybe the product of the two could be useful for people in that field, sort of how ISP is useful to people in rocketry but us normal people need to divide it by G(earth) to get something intuitive.
    - guenthert 1y ago
      I don't think it's obscure in that field or for the target audience. You might want to read the soon to be published distilled and transposed article in popular mechanics ...
    - rbanffy 1y ago
      It’s mentioned in Contact, both movie and book.
      - dotancohen 1y ago
        Thanks. That was one of only two movies based on a book that I enjoyed as much as the book.
- hdgvhicv 1y ago
  erg s−1 Hz−1 Gave me a headache
sema4hacker 1y ago
Every day Hacker News titles, stories, and comments have acronyms and abbreviations I've never seen before, and I have to search for the term to know what it's talking about. I know what a parsec is, but I've never actually seen the pc abbreviation used before. At least I learn something new every day.
- a1o 1y ago
  You didn't mention but I guess pc here stands for parsecs
  - deleted 1y ago
    [deleted]
- DrBazza 1y ago
  Barns was a particular favourite from my university years. Imagine my surprise encountering 'mb' and it wasn't millibars. Then again, I also had to deal with microhertz and nanohertz.
  - pezezin 1y ago
    At least it wasn't megabytes... Spoiler: "megabytes" are abbreviated as MB, but many people don't see to remember that SI units are case-sensitive.
    - fc417fc802 1y ago
      Also keep in mind the difference between MB and MiB. You almost never want MB. You usually either want MiB or Mb.
roughly 1y ago
I am generally well read across a wide variety of fields, but now and again I come across a sentence or paragraph where the sheer density of information packed into a small number of well-chosen field-specific terms just stops me in my tracks. The abstract for this paper is a testament to the ability of jargon to increase the information carrying capacity of the limited bitrate of human language - it hit my head like a zip bomb.
- __MatrixMan__ 1y ago
  It gives me flashbacks to the last time I tried to figure out what a sheaf was.
- AmazingTurtle 1y ago
  You should have said "it hit my head like a zip bomb", it was unclear to me what you meant till I read the whole paragraph
- andrecarini 1y ago
  As another reader who has no idea what any of this is about, I've coerced my favorite LLM to digest it into ooga-booga format in the style of this essay[1]: # grug see big sky boom - sky make ooga FLASH but not light, just invisible whoosh (radio). - whoosh so strong, like sun work many day, but all squish into blink of eye. - smart sky-people have big ear rock (CHIME). ear rock say: "boom come from there, galaxy far, but not too far (only 130 million fire-circles (light years) away)." - ear rock also have many little ear-brother rock across land, help point finger very good. - finger point so good, sky-people know spot of boom smaller than tree forest (13 parsec). - then, magic glass eye (James Webb) look at spot. see old fat star (red giant) glowing soft. - but fat star not make ooga boom. hmm. maybe fat star have sneaky tiny angry friend (neutron star). - tiny angry friend go "KRAK!" → make fast radio boom. # lesson for tree-brain - boom in sky still big mystery. - now smart sky-people can say where boom come from. - if know where, can watch with other eyes, maybe find secret of why. - grug think: many sky boom = maybe angry tiny stars yelling far away. # Ooga booga translation: "Tree no know why sky yell. But now tree know where sky yell. Soon, tree maybe know why sky yell." [1]: https://grugbrain.dev/ https://grugbrain.dev/
AndrewKemendo 1y ago
My interpretation of the paper: Astronomers processed a bunch of data from a fairly new antenna array (CHIME) and saw a giant burst of energy in radio range (above 20khz), localized to a 10 light year “bubble” of space, that is relatively close to us, as a novel measurement precision James Webb then also correlated an IR signal near this radio signal So it seems to me that we’re finally just seeing for the first time the actual data that is coming into earth, a lot of the analysis seems to think this is a new thing but in fact it’s simply just new for us to be able to measure CHIME nor these methods existed previously to the last 5 years so we’re likely going to see a lot of what we just haven’t been seeing. It doesn’t mean it’s new it just means astronomers are getting better tools to continue to refine the granularity of measurements
- magicalhippo 1y ago
  A cool thing about CHIME is that they focus after the fact, by the way they process the data. A nice overview talk can be found here[1], which also goes into the objects it detects such as FRBs. CHIME is also used to detect millisecond pulsars, and is part of the NANOGrav[2] pulsar timing array, which measures very low frequency gravitational waves from merging supermassive black holes and such. [1]: https://pirsa.org/22100067 https://pirsa.org/22100067 [2]: https://nanograv.org/15yr/Summary/Timing https://nanograv.org/15yr/Summary/Timing
- katzenversteher 1y ago
  My interpretation of the title (did not read the article but I don't understand anything about astrophysics anyways): ALIENS!
- drmpeg 1y ago
  This is pretty pedantic, but allocated radio frequencies start at 8.3 kHz. https://www.fcc.gov/sites/default/files/fcctable.pdf https://www.fcc.gov/sites/default/files/fcctable.pdf
SiempreViernes 1y ago
Wow, I haven't followed the FRBs field closely so discovering they are being localised to spatially resolved places within galaxies is amazing! Good job Canada getting CHIME built and keeping it running.
Veliladon 1y ago
> nearby (40 Mpc) Perspective is always so interesting. I’ve never thought of anything 130 million light years to be nearby but on a universe spanning scale it kind of is.
- MontagFTB 1y ago
  It came into perspective for me when I heard astrophysicists may round pi to 1 and pi^2 to 10 in calculations.
  - wildzzz 1y ago
    I took one semester on astrophysics. The unit they use and the number rounding involved is so different compared to other fields. First, they use centimeters and grams. Why? Because that's what was used before SI units came to be. Why? Because it's a tradition. With this system, you get very large exponents when using scientific notation. The funny thing is that the coefficient of any number isn't terribly important. As long as you were within a factor of 10, that was close enough. Compare that to other engineering fields, if I design a portable device that I say will draw max 2W but actually draws 8W, that's probably going to be a problem. Another funny thing is that the cgs unit system uses ergs instead of joules. 1 erg is the equivalent to a mosquito taking flight yet we use this for calculating the energy of a star??? In the abstract, they use the unit erg s^-1 Hz^-1. In other RF fields, we would use dBm/Hz which is a measure of power spectral density. 10^29 erg s^-1 Hz^-1 is equivalent to 260dBm/Hz.
- agos 1y ago
  in certain fields of astronomy, they forego units of distance and use redshift (z) to talk about how "far" things are
teepo 1y ago
Do scientists think fast radio bursts come from neutron stars or magnetars? And with new tools like CHIME and VLBI, can we figure out if some of these bursts actually repeat? I'm still fascinated at the prospect of these "star quakes" or magnetic flares that emerge from these stars. I guess these fields would weaken over time, but does it really maintain it's mass, just lose rotation speed or something?

95 points by gnabgib 1y ago

addaon 1y ago

Is kJy as a brightness unit the abomination I think it is?

bqmjjx0kac 1y ago
You nerd sniped me :) In this context, I believe it is a kilo-Jansky, not a kilo-Joule * year. https://en.wikipedia.org/wiki/Jansky https://en.wikipedia.org/wiki/Jansky
- dotancohen 1y ago
  I don't think that replacing two ill fitting but probable units with a single obscure unit is much of an improvement!
  - 8bitsrule 1y ago
    It appears to have something to do with CGS units. 1 Jy = 10-23 erg s-1 cm-2 Hz-1 (cgs) only their figure: L9.9 GHz < 2.1 × 10^25 erg s−1 Hz−1 leaves out the cm-2. (So not a density, like Jy. Perhaps 'L' is luminosity? ... As in: "The solar luminosity unit is a measure of the Sun's radiant energy and is equal to 3.828×10^(26) Watts." -(NRAO) While groping, I found this helpful page called Brightness in Radio Astronomy: http://physics.wku.edu/~gibson/radio/brightness.html http://physics.wku.edu/~gibson/radio/brightness.html
    - dotancohen 1y ago
      I was thinking maybe joules/year e.g. energy/time might be some brightness indicator for some astronomical definition of brightness - especially in the non-optical wavelengths. But that's division, not multiplication. Another thread in my brain thought maybe the product of the two could be useful for people in that field, sort of how ISP is useful to people in rocketry but us normal people need to divide it by G(earth) to get something intuitive.
  - guenthert 1y ago
    I don't think it's obscure in that field or for the target audience. You might want to read the soon to be published distilled and transposed article in popular mechanics ...
  - rbanffy 1y ago
    It’s mentioned in Contact, both movie and book.
    - dotancohen 1y ago
      Thanks. That was one of only two movies based on a book that I enjoyed as much as the book.
hdgvhicv 1y ago
erg s−1 Hz−1 Gave me a headache

sema4hacker 1y ago

Every day Hacker News titles, stories, and comments have acronyms and abbreviations I've never seen before, and I have to search for the term to know what it's talking about. I know what a parsec is, but I've never actually seen the pc abbreviation used before. At least I learn something new every day.

a1o 1y ago
You didn't mention but I guess pc here stands for parsecs
- deleted 1y ago
  [deleted]
DrBazza 1y ago
Barns was a particular favourite from my university years. Imagine my surprise encountering 'mb' and it wasn't millibars. Then again, I also had to deal with microhertz and nanohertz.
- pezezin 1y ago
  At least it wasn't megabytes... Spoiler: "megabytes" are abbreviated as MB, but many people don't see to remember that SI units are case-sensitive.
  - fc417fc802 1y ago
    Also keep in mind the difference between MB and MiB. You almost never want MB. You usually either want MiB or Mb.

roughly 1y ago

I am generally well read across a wide variety of fields, but now and again I come across a sentence or paragraph where the sheer density of information packed into a small number of well-chosen field-specific terms just stops me in my tracks. The abstract for this paper is a testament to the ability of jargon to increase the information carrying capacity of the limited bitrate of human language - it hit my head like a zip bomb.

__MatrixMan__ 1y ago
It gives me flashbacks to the last time I tried to figure out what a sheaf was.
AmazingTurtle 1y ago
You should have said "it hit my head like a zip bomb", it was unclear to me what you meant till I read the whole paragraph
andrecarini 1y ago
As another reader who has no idea what any of this is about, I've coerced my favorite LLM to digest it into ooga-booga format in the style of this essay[1]: # grug see big sky boom - sky make ooga FLASH but not light, just invisible whoosh (radio). - whoosh so strong, like sun work many day, but all squish into blink of eye. - smart sky-people have big ear rock (CHIME). ear rock say: "boom come from there, galaxy far, but not too far (only 130 million fire-circles (light years) away)." - ear rock also have many little ear-brother rock across land, help point finger very good. - finger point so good, sky-people know spot of boom smaller than tree forest (13 parsec). - then, magic glass eye (James Webb) look at spot. see old fat star (red giant) glowing soft. - but fat star not make ooga boom. hmm. maybe fat star have sneaky tiny angry friend (neutron star). - tiny angry friend go "KRAK!" → make fast radio boom. # lesson for tree-brain - boom in sky still big mystery. - now smart sky-people can say where boom come from. - if know where, can watch with other eyes, maybe find secret of why. - grug think: many sky boom = maybe angry tiny stars yelling far away. # Ooga booga translation: "Tree no know why sky yell. But now tree know where sky yell. Soon, tree maybe know why sky yell." [1]: https://grugbrain.dev/ https://grugbrain.dev/

AndrewKemendo 1y ago

My interpretation of the paper: Astronomers processed a bunch of data from a fairly new antenna array (CHIME) and saw a giant burst of energy in radio range (above 20khz), localized to a 10 light year “bubble” of space, that is relatively close to us, as a novel measurement precision James Webb then also correlated an IR signal near this radio signal So it seems to me that we’re finally just seeing for the first time the actual data that is coming into earth, a lot of the analysis seems to think this is a new thing but in fact it’s simply just new for us to be able to measure CHIME nor these methods existed previously to the last 5 years so we’re likely going to see a lot of what we just haven’t been seeing. It doesn’t mean it’s new it just means astronomers are getting better tools to continue to refine the granularity of measurements

magicalhippo 1y ago
A cool thing about CHIME is that they focus after the fact, by the way they process the data. A nice overview talk can be found here[1], which also goes into the objects it detects such as FRBs. CHIME is also used to detect millisecond pulsars, and is part of the NANOGrav[2] pulsar timing array, which measures very low frequency gravitational waves from merging supermassive black holes and such. [1]: https://pirsa.org/22100067 https://pirsa.org/22100067 [2]: https://nanograv.org/15yr/Summary/Timing https://nanograv.org/15yr/Summary/Timing
katzenversteher 1y ago
My interpretation of the title (did not read the article but I don't understand anything about astrophysics anyways): ALIENS!
drmpeg 1y ago
This is pretty pedantic, but allocated radio frequencies start at 8.3 kHz. https://www.fcc.gov/sites/default/files/fcctable.pdf https://www.fcc.gov/sites/default/files/fcctable.pdf

SiempreViernes 1y ago

Wow, I haven't followed the FRBs field closely so discovering they are being localised to spatially resolved places within galaxies is amazing! Good job Canada getting CHIME built and keeping it running.

Veliladon 1y ago

> nearby (40 Mpc) Perspective is always so interesting. I’ve never thought of anything 130 million light years to be nearby but on a universe spanning scale it kind of is.

MontagFTB 1y ago
It came into perspective for me when I heard astrophysicists may round pi to 1 and pi^2 to 10 in calculations.
- wildzzz 1y ago
  I took one semester on astrophysics. The unit they use and the number rounding involved is so different compared to other fields. First, they use centimeters and grams. Why? Because that's what was used before SI units came to be. Why? Because it's a tradition. With this system, you get very large exponents when using scientific notation. The funny thing is that the coefficient of any number isn't terribly important. As long as you were within a factor of 10, that was close enough. Compare that to other engineering fields, if I design a portable device that I say will draw max 2W but actually draws 8W, that's probably going to be a problem. Another funny thing is that the cgs unit system uses ergs instead of joules. 1 erg is the equivalent to a mosquito taking flight yet we use this for calculating the energy of a star??? In the abstract, they use the unit erg s^-1 Hz^-1. In other RF fields, we would use dBm/Hz which is a measure of power spectral density. 10^29 erg s^-1 Hz^-1 is equivalent to 260dBm/Hz.
agos 1y ago
in certain fields of astronomy, they forego units of distance and use redshift (z) to talk about how "far" things are

teepo 1y ago

Do scientists think fast radio bursts come from neutron stars or magnetars? And with new tools like CHIME and VLBI, can we figure out if some of these bursts actually repeat? I'm still fascinated at the prospect of these "star quakes" or magnetic flares that emerge from these stars. I guess these fields would weaken over time, but does it really maintain it's mass, just lose rotation speed or something?