stosb

wearer of programming socks

  • she/her

mid 20s | bisexual | programmer | european


profile pic: a picrew by Shirazu Yomi
picrew.me/en/image_maker/207297
i use arch btw
xenia the linux fox -> πŸ¦ŠπŸ³οΈβ€βš§οΈ
the moon
πŸŒ™

8akesale
@8akesale

So, most of my current research is on pulsars and pulsar accessories. Part of me wants to go "ok everyone knows what a pulsar is so let's go straight to talking about the advanced stuff" and then i remember that one xkcd comic about experts so:
Flareon fursona in a vaguely witchy outfit.

Pulsars are rapidly rotating neutron stars with bright β€œbeams” of radiation that sweep across the sky. When these beams happen to cross over Earth, we detect a β€œpulse”, much like a lighthouse appears to pulse as it sweeps across a given vantage point.


8akesale
@8akesale

ok wait we should probably talk about neutron stars first,

so stars are, by and large, big balls of hydrogen plasma. gravity wants to squish them down very very small, but when you squeeze things they get hot and hot hydrogen fuses with other hot hydrogen to make REALLY hot helium. hot things generate a lot of pressure, and a lot of light, and the light also generates a bit of pressure. eventually gravity and the fusion heat pressure balance out and you've got this remarkably stable plasma orb

but eventually the hydrogen runs out, and if the star had enough mass there's helium flash asymptotic giant branch shell burning etc etc eventually it explodes in a supernova

the supernova ends up leaving something behind, depending on how massive the progenitor star was. everyone knows black holes, which is the supernova remnant from the really big fuckers, but smaller (but still big) stars end up leaving behind a neutron star

what happens is the supernova is the outer layers of the star. the iron core is mostly intact but still VERY massive and iron doesn't fuse (long story involving nucleon binding energies) so you don't end up getting the heat to balance gravity and gravity gets VERY excited about this. the iron atoms get squished so hard that the electrons get shoved into the protons and turn into neutrons

so, a neutron star is just a ball of neutrons held up from gravity purely based on the fact that neutrons REALLY don't want to exist in the same space as other neutrons.


8akesale
@8akesale

and now we can talk about pulsars properly. you know how when you stick your arms out and spin in an office chair and then pull your arms in you spin faster?

magnetic fields don't really do that, but it's close enough that it works as a good analogy. the progenitor star's magnetic field got REALLY strong after the whole supernova + core collapse + L + ratio incident

earth's magnetic field is offset from the rotation axis, right? the north pole is not the same as the north magnetic pole? this happens with neutron stars too

and through some mechanism we don't really understand, the magnetic field forms two beams of radiation, one at each pole. since they're not aligned with the rotation axis, they end up sweeping across the sky as the neutron star itself spins. they're big ol' lighthouses in space


8akesale
@8akesale
Flareon fursona in a vaguely witchy outfit.

+SHELLBURNING +IRONFUSION +CORECOLLAPSE +SUPERNOVA +SYNCHROTRON +JANSKIED


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in reply to @8akesale's post:

in reply to @8akesale's post:

in reply to @8akesale's post:

you know how when you stick your arms out and spin in an office chair and then pull your arms in you spin faster?

ok i know this is not the point of the post but thank you for reminding me about this thing, it turns out this is pretty fun

in reply to @8akesale's post:

Where's my weird sci fi about using the pulses of a neutron star to navigate around dangerous space, no I don't care how wildly impractical an idea that is compared to any other means of navigation available to someone with the means to be in space