A BRIEF INTRODUCTION
Two stars orbit each other in a gravitational tango. One, in death throes, has collapsed to extremely small dimensions, warping the space around it. Gas
from the companion star falls into the gravitational embrace of the compact
object, getting so hot that it shines in the X-ray waveband. On top of all
this, jets are shooting out along the poles at near the speed of light.
The picture we have just painted is that of a microquasar - a special
breed of X-ray binary stars. Microquasars, which have both disk accretion
and relativistic jets, mimic the behavior of a quasars. However, quasars are
formed in the center of galaxies whereas microquasars are formed in binary
star systems. This means that microquasars operate on a much smaller
(and consequently much faster) scale. The study of binaries is crucial to
astronomy because it is one of the primary methods by which we can measure
the masses of the stars. Also, because angular momentum is conserved, the
orbital period of the binary gives clues to the system's formation. X-ray
binaries - a system containing a compact object and a less evolved star - are
particularly important because they tell us about the evolution of massive
stars and allow us to probe extreme physical conditions near the surface of
the compact object. The study of microquasars gives insight to an additional
bizarre phenomenon: jet formation. What causes a compact object,
warping spacetime and accreting material at high rates, to also
eject material at near the speed of light?
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