Scientists have detected the warping of space generated by the collision of two dead stars, or neutron stars, at the same time as observing light from the same cosmic event.
They have confirmed that such mergers lead to the production of the gold and platinum that exists in the universe.
An artist's illustration of two merging neutron stars. The narrow beams represent the gamma-ray burst while the rippling space-time grid indicates the isotropic gravitational waves that characterise the merger. Photo: AFP / National Science Foundation / LIGO / Sonoma State University / A. Simonnet
The waves, caused by the collision of two neutron stars some 130 million years ago, were first detected in August by the Laser Interferometer Gravitational-Wave Observatories, known as LIGO, in the United States as well as at a third detector named Virgo in Italy.
The discovery enabled telescopes all over the world to capture details of the merger as it unfolded.
David Reitze, executive director of the LIGO Laboratory at Caltech in Pasadena, California, said: "This is the one we've all been waiting for."
The outburst took place in a galaxy called NGC 4993, located roughly a thousand billion, billion kilometres away, in the Constellation Hydra.
The stars themselves had masses 10-20 percent greater than our sun but were no larger than 30km across.
They were the crushed leftover cores of massive stars that long ago exploded as supernovas.
They are called neutron stars because the process of crushing the star makes the charged protons and electrons in the atoms of the star combine - to form an object made entirely of neutrons.
Such remnants are incredibly dense - a teaspoonful would weigh a billion tonnes.
Less than two years have passed since scientists working at the Massachusetts Institute of Technology and the California Institute of Technology first detected gravitational waves coming off two black holes.
The gravitational waves had been predicted by Einstein in 1916, as an outgrowth of his groundbreaking general theory of relativity, which depicted gravity as a distortion of space and time triggered by the presence of matter.
Three US scientists who made that discovery were awarded the Nobel prize in physics earlier this month.
The findings published on Monday help confirm Einstein's theory, said the researchers.
"Imagine that gravitational waves are like thunder," astronomer Philip Cowperthwaite, of the Harvard-Smithsonian Center for Astrophysics, said in a statement. "We've heard this thunder before, but this is the first time we've also been able to see the lightning."
The LIGO instruments work in unison and use lasers to detect remarkably small vibrations from gravitational waves as they pass through the earth.
Researchers had suspected that the huge release of energy leads to the creation of rare elements, such as gold and platinum.
Dr Kate Maguire, from Queen's University Belfast, who analysed the collision's burst of light, said that the theory was now proven.
"Using some of the world's best telescopes, we have discovered that this neutron star merger scattered heavy chemical elements, such as gold and platinum, out into space at high speeds.
"These new results have significantly contributed to solving the long-debated mystery of the origin of elements heavier than iron in the periodic table."
- BBC / Reuters
