John D. Gwinner kirjutas:
"Logan Kearsley" wrote in message
news:3HlMh.15796$1a6.14446@trnddc08...
How close to Earth?

I can hand wave FTL; I haven't decided if this occurs before or after cyber
enhanced telekinetics discover how to fold space (mumble mumble). It could
also be thousands of years from now. So any distance is fine.

I don't think you'll manage anyplace where plants will
grow, unless you add a companion star or arrange for a lot of
phosphorescence. But you can definitely get a planet that's close to
Earth's
size and the right temperature, and a thick atmosphere or living on the
darkside will protect you from radiation.

I don't mind adding a companion - the issue with companions is that they
seem to produce a lot of Nova's or at the minimum an accretion ring (from
the stellar winds). Then you get blackbody radiation that's so hot it
produces hard XRays.

I'm looking to download an NS catalog and see if these things exist.

The thing with Astronomer's is that they often observe things that are
interesting. A cool NS with a companion just isn't very exciting.


Also, they observe things that are bright.

Massive accretion and novas would particularly happen to neutron stars
whose companion is a giant spilling over Roche lobe.

A neutron star whose companion is a quiet main-sequence star would
pick up some small amount of stellar wind, but much less than a giant
would cause, and if the neutron star is old, having dissipated much of
its spin, magnetic field and internal heat, it could well be not a
pulsar.

Compare the nearby white dwarves, Sirius and Procyon systems. They are
visible because they are so near and have bright A or F companions.
Sirius system is IIRC 800 millions of years old. Sirius B is obviously
younger.

How much of the brightness of Sirius B or Procyon B is from stored
internal heat, how much from accretion? How old are they as white
dwarves?