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Comment by malux85 | Hacker News Reader

This type of emission is not directed, right? Which means it's not firing "at" anything, it's just emitting in all directions.

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Pulsars shoot beams out of their magnetic poles so they are directed but in a beam. Even the narrowest would be lots of stars. They are also spinning so they sweep a larger area.

My natural first question is. If it is coming out of the pole, why is it sweeping?

My guess, nothing is perfect, the rotation pole does not align exactly with the magnetic pole.

A second followup question, do stars tend to be coaxially aligned with their galaxy? it it possible to tell which way a star or pulsar is rotating?

This is called the pulsar’s magnetic inclination and it’s often quite far from 0, all the way to nearly orthogonal.

Yes but this is a dynamic process that produces more correlated stars as the galaxy ages.

Astronomers routinely measure such parameters using models to provide confidence bounds for their estimates.

https://arxiv.org/pdf/2404.13857

This type of emission may be directed (or at least, emitted by something rotating, so directed at different locations around a circle as it rotates). That would leave it firing at Earth some of the time, and firing other places at other times.

Or, it could be something that flares up every 44 minutes, and is emitted in all directions at once. We really don't know.

If Earth is in the "sweep" of that rotation, the rise and falloff of the (continuous) signal will follow strict gaussian slopes outside the main beam, due to long-range diffraction.

Pulses could follow such a slope, too, but might not, and that would provide differentiation.

Yeah. Unfortunately, the fine article gave no such details that I could see...

That's a good point, I didn't catch any explanation for that choice of wording. Wonder if it was intentional.

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