A highly magnetised rotating compact star (black hole, neutron star, white dwarf) that emits beams of electromagnetic radiation out of its magnetic poles.
Questions tagged [pulsars]
66 questions
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Due to relativity, does the surface of a pulsar have less area than the layer beneath it?
A pulsar or spinning neutron star can reach relativistic angular velocities. Special relativity asserts that objects traveling near the speed of light contract in length. Therefore, it seems reasonable that a rapidly rotating object could exhibit a…
Master Drifter
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Is it possible that all neutron stars are actually pulsars?
I'm assuming that what I've been told is true:
We can only detect pulsars if their beams of electromagnetic radiation is directed towards Earth.
That pulsars are the same as neutron stars, only that they emit beams of EM radiation out of their…
Jonathan.
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What causes millisecond pulsars to speed up?
Millisecond pulsars are supposed to be old neutron stars. However, they are spinning even more rapidly than newly formed pulsars. Since pulsars slow down as they age, something must have caused these older pulsars to "spin up" and be rotating as…
dagorym
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Why are non-relativistic methods used in binary pulsar systems (gravitational waves)?
Although gravitational waves are a subject of the General Relativity, why do most books use Newtonian equations of motion for power radiated and rate of change of eccentricity calculations? In most books ("Gravitation, Foundation and Frontiers", by…
user135580
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How can a pulsar slow down?
I saw in some astronomy textbooks that pulsars gradually slow down due to the loss of energy by its radiation. I wonder why this is possible?
Although the radiation is now not thermal but in the form of two beams, I think they still cannot carry…
velut luna
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Why are pulsar's radiation beams collimated?
Every picture of a pulsar I see shows a very collimated radiation beam. What is the mechanism generating such a collimation?
Note: I am not talking about "relativistic jets". I am talking about radiation, not matter.
Diracology
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Where to find information on the pulsar map written to Voyager's golden record?
Where might I find details about the pulsar map written on the Voyager's golden record?
This diagram defines the location of our Sun utilizing 14
pulsars of known directions from our sun. The binary
code defines the frequency of the pulses.
mate64
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2 answers
Difference between gravitational wave detectors
There are a lot of different gravitational wave detectors and they all have their own wave period and frequency they operate at. This picture shows that
The last three (pulsar timing, space interferometers and terrestrial interferometers) use the…
BOB
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Why were pulsars not discovered in the visual spectrum?
In 1967, the first pulsar was discovered at a radio observatory in Cambridge.
Radio astronomy started around the 1930s, but astronomy in the visible part of the spectrum had been done for a long time by then.
Was it a coincidence that no observation…
pfincent
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How is angular momentum stored in the superfluid component of pulsars?
I am trying to understand current theories about why pulsars glitch. I have come across two explanations that I'm assuming are complementary, but which I am having trouble reconciling.
The inner super-fluid component is spinning faster than the…
user363165
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Do the magnetic moments of neutrons mutually align to produce the magnetic field and emission beams of a pulsar and/or magnetar?
In this graphic of a pulsar the emission beams are at the north and south poles of the neutron star's magnetic field.
I've read that the Earth's magnetic field is produced by a dynamo effect, whereby convection currents in the electrically…
Ernie
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Do neutron stars emit stellar flares?
Since stellar flares are formed from the magnetic energy of a star, is it probable to assume that neutron stars can emit stellar flares as well? If so, how would the super fluid material of the star behave? Would there be anyway to observe such…
Neuromeda
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Biermann Mechanism
Biermann mechanism says that due to different masses of electrons and protons, the motion of former leads to the latter. This effect produces non-zero circular currents which induce vertical magnetic fields.
I wanted to prove if density and pressure…
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How did Jocelyn Bell aim her radio telescope (phased array)?
In 1967 Jocelyn Bell discovered pulsars using the Cambridge University radio telescope - a two hectare field of posts and wires.
The pulsar was found to be in the constellation Vulpecula. How did she locate the pulsar? In other words, how do you…
Peter4075
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Can you use pulsar observations to determine absolute time? How long can you go without anything else?
In this old answer of Steve Allen's, he quotes this nice passage
Imagine for a moment what would happen if, just as a practical joke, someone found a way to stop all atomic clocks, just for a short time. This would cause such a tremendous…
Emilio Pisanty
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