|MadSci Network: Astronomy|
Our current model of a pulsar is that it consists of a rotating neutron star left over from a supernova. For a pulsar to form near the earth, we would have to have a local supernova, which would of course be a doomsday scenario of far greater concern than the pulsar. But if, say a pulsar travelling through space passed near the earth there would be several effects. First, the high level of radiation which they emit would impact the upper atmosphere. The atmosphere itself would, however, shield us from most of the x-rays and charged particles. Second, pulsars have very strong magnetic fields, and the pulsar would definitely accelerate particles near the earth to create a very powerful radiation field. Interplanetary magnetic fields are very complex, but it would no doubt cause massive geomagnetic storms on Earth. This would knock out power grids and possibly allow radiation from space to sneak down to the surface. Pulsars also emit powerful radio waves, which would cause problems with any electrical equipment on earth. All of these phenomena would depend strongly on its distance to the Earth and whether or not the strong emission from the magnetic poles pointed towards us. If it was close enough to affect the Earth directly, you might also consider how the Sun would react. The presence of a pulsar could cause massive flares and solar storms, which would in turn affect the Earth. At the closest range, we would worry about the gravitation of a pulsar affecting our planet and the Sun, causing problems with tides and shifting the crust of the Earth. Also, if the pulsar was close enough our orbit would shift, possibly sending us crashing into the pulsar itself. In short, we really don't want a pulsar anywhere near here. --
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