Wandering Black Holes On the Outskirts of the Solar Neighborhood

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Paris – September 27, 2001 – Issue #281

ON THE OUTSKIRTS OF THE SOLAR NEIGHBORHOOD.

A wandering black hole was picked
up and followed by a team of astronomers from the French Atomic Energy
Commission (CEA), the US National Radio Astronomy Observatory and the
European Southern Observatory (ESO), and the results of this bit of galactic
gumshoe-ing shed new light on (instead of into) this voracious phenomenon as
well as on the formative stages of our galaxy. Using radio telescopes to
detect the turbulent radiation wreaked by a black hole as it passes near
other bodies, the research team compared these readings with plates of
optical images taken at the Mount Palomar facilities in order to determine
the hole’s exact trajectory, thereby becoming the first ever to reconstruct
a moving “picture” of a black hole. By then comparing this trajectory with
known galactic paths, they were able to state without hesitation that this
hole was not the remnants of a star from the galactic plane (a galaxy’s main
concourse), whose speed and path would be quite different from those
observed, but rather the late phase of a very old star such as are
stockpiled in the halo, or outer galactic whirl of globular clusters. In
short, this work constitutes the first glimpse astronomers have had into the
formation of large stars in the early moments of the Milky Way. (Commission
d’Energie Atomique, http://www.cea.fr)