When astronomers say there are trillions of comets beyond the orbit of
Pluto, are they still considered a part of our solar system?
The boundary of our solar system extends at least as far into space as the so-
called Bow Shock, where the solar wind slams up against the interstellar
medium. This is thought to occur at about 100 - 200 Astronomical Units from
the Sun, or 2-5 times the orbital distance of Pluto. Beyond that, the Sun
would still exert gravitational influences out to a few light years which
would define the Sun's sphere of influence. So, the Oort Cloud and its
trillions of cometary nuclei bodies is still considered a part of our solar
system.
Copyright 1997 Dr. Sten Odenwald
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