The plots show
signals of gravitational waves detected by the twin LIGO observatories.
The signals came
from two merging black holes 1.3 billion light-years away.
The top two plots
show data received at each detector, along with waveforms predicted
by general
relativity. The X-axis plots time, the Y-axis strain—the fractional amount by
which distances
are distorted. The LIGO data match the predictions very closely.
The final plot
compares data from both facilities, confirming the detection. Credit: LIGO
(February 11, 2016) LIGO
opens new window on the universe with observation of gravitational waves from
colliding black holes
For the first time, scientists have observed ripples in the
fabric of spacetime called gravitational waves, arriving at the earth from a
cataclysmic event in the distant universe. This confirms a major prediction of
Albert Einstein's 1915 general theory of relativity and opens an unprecedented
new window onto the cosmos.
Gravitational waves carry information about their dramatic
origins and about the nature of gravity that cannot otherwise be obtained.
Physicists have concluded that the detected gravitational waves were produced
during the final fraction of a second of the merger of two black holes to
produce a single, more massive spinning black hole. This collision of two black
holes had been predicted but never observed.
The gravitational waves were detected on September 14, 2015
at 5:51 a.m. Eastern Daylight Time (09:51 UTC) by both of the twin Laser
Interferometer Gravitational-wave Observatory (LIGO) detectors, located in
Livingston, Louisiana, and Hanford, Washington, USA. The LIGO Observatories are
funded by the National Science Foundation (NSF), and were conceived, built, and
are operated by Caltech and MIT. The discovery, accepted for publication in the
journal Physical Review Letters, was made by the LIGO Scientific Collaboration
(which includes the GEO Collaboration and the Australian Consortium for
Interferometric Gravitational Astronomy) and the Virgo Collaboration using data
from the two LIGO detectors.