|
Mercury,
Sep/Oct 2001 Table of Contents
|

|
|
Courtesy
of LIGO.
|
A
team of physicists is opening a new window to the universe, the
realm of ripples in space-time.
by
Kenneth G. Libbrecht
On
the scrub desert plain of the Hanford Nuclear Reservation in Washington,
and in the flat pine forest of Livingston Parish in Louisiana, scientists
have constructed two grand new astronomical tools to open a new
window to the observable universe. Carved into the wilderness at
both sites are immense gravitational-wave antennae, built inside
L-shaped above-ground tunnels, with arms four kilometers long. The
tunnels house and protect vacuum pipes, which provide clear passage
for infrared laser beams. The laser beams bounce off carefully suspended
mirrors at the ends of the pipes, measuring minuscule perturbations
of space-time produced by passing bursts of gravitational radiation.
These
facilities together make up the Laser Interferometer Gravitational-Wave
Observatory, or LIGO (pronounced LIE-go), a joint project of the
California Institute of Technology and the Massachusetts Institute
of Technology, funded by the National Science Foundation. The LIGO
project is the culmination of many decades of research and technology
development, and along with its sister projects around the world,
we soon hope to usher in an era of gravitational-wave astronomy.
|
|