Pulsar stars?

[Algaib]

If our sun was replaced by a pulsar, would our solar system be sucked into it because of the increased gravity? How long would it take? Would we burn up because of the increased heat? How long would it take? Does it still emit visable light or only x-rays etc..? Would the light on earth be observed as a 'strobe'? (if the rotation of the pulsar was slow enough to see, say a few seconds.)

[zhermes]

Our solar system would not be sucked in.
If the sun was replaced by a solar mass pulsar, the gravity would be exactly the same.

The pulsar's emission spectra would depend largely on its evolutionary state, surface temperature, and local environment. It would be (at least) significantly dimmer in the visual.

The strobes and level of x-ray emission would depend sensitively on the orientation of the pulsar's magnetic field axis to the orbital plane of the earth. Generally the magnetic field is perpendicular to the orbital plane, and thus we would not see (or be exposed) to the pulses.

[Algaib]

What if you had a pulsar with much more mass than the sun, say enough to pull everything into it, how long would that process likely take? For Earth to fall in?

[zhermes]

Things still wouldn't be pulled in, it would just change their orbits.
Its very possible the new configuration would be unstable however.... and eventually some planets would collide with the sun, or others would be ejected from the system. There is no predictable amount of time that would take without doing the calculations. Most like between millions and billions of years.

[Radrook]

Pulsar Effect on Planets Videos
http://www.google.com/search?sourceid=ie7&q=pulsars+effect+on+their+planets&rls=com.microsoft:en-us:IE-SearchBox&ie=UTF-8&oe=UTF-8&rlz=1I7ACAW_enUS378US378#q=pulsars+effect+on+their +planets&hl=en&rls=com.microsoft:en-us:IE-SearchBox&rlz=1I7ACAW_enUS378US378&prmd=ivns&source=univ&tbs=vid:1&tbo=u&sa=X&ei=VcJrTfefLsPogAfsnNnLCg&ved=0CFsQqwQ&bav=on.1,or.&fp=e63e90ac70623278

One thing to keep in mind is that pulsars are rotating neutron stars resulting from supernova explosions. So any planets that were present at the time of that event were bathed in the resultant radiation. There are actually rocky planets that have been detected around a pulsar. Neutron star, PSR B1257+12, was the first. Here is an article concerning this.

Planets around pulsars:
http://www.astro.psu.edu/users/alex/pulsar_planets_text.html