Astronomers Witness Two Neutron Stars Merging and Creating Gold, Platinum

Video This artist’s view shows the moments before and the nine days following a kilonova. Two neutron stars spiral inward creating gravitational waves. After the merger a jet produces gamma rays, while expanding radioactive debr

Origin of Universe's heavy elements, ranging from gold to uranium, has finally been confirmed, after a gravitational wave source was seen and heard for the first time ever by an global collaboration of astronomers and astrophysicists. We haven't been able to register light from these events with any other instruments.

Scientists at Syracuse University were part of the team that recently discovered evidence of the creation of gold and platinum through the collision of neutron stars, the first time scientists identified a neutron star collision. The neutron stars merged in a galaxy called NGC 4993, located about 130 million light years from Earth in the constellation Hydra. The Laser Interferometer Gravitational-Wave Observatory (LIGO), which is based in the USA, the Virgo detector (based in Europe) were behind the discovery, with 70 different observatories. Astronomers worked together to locate the area where the merger occurred. And because the neutron stars are so small, they can get very close to each other before merging, twirling around each other faster and faster as they approach each other.

RUMOURS have been swirling for weeks that scientists have detected gravitational waves - tiny ripples in space and time - from a source other than colliding black holes.

"Now, astronomers won't just look at the light from an object, as we've done for hundreds of years, but also listen to it", Tanvir said.

At around 10 a.m. EDT (1400 GMT), a little more than an hour after the gravitational wave was detected at the LIGO observatories, the astronomical community across the world was notified.

Brown, Ballmer and Peter Saulson, another physics professor, were part of the Nobel Prize-winning team that detected gravitational waves for the first time past year. This latest signal was detected on August 17. While the previous signals had lasted for just a fraction of a second, this time it prevailed over a minute and a half.

Previous detections of gravitational waves have all involved the merger of two black holes, a feat that won the 2017 Nobel Prize in Physics earlier in October. Typically 20 kilometers (12 miles) in diameter, a neutron star is radioactive and has a mass slightly more dense than the sun in our solar system. "So you can observe the waves for a long time, and get a nice, long, handsome signal", Laura Cadonati, a LIGO collaborator and professor of physics at Georgia Institute of Technology, told the publication.

At almost the same time, NASA's Fermi space telescope had detected a burst of gamma rays. In fact, the gravitational waves of the neutron star merger were detected on Earth first, even before the gamma ray burst.

In the meantime, the astronomers thought that Virgo observatory had missed the signal, as it was not visible in the observatory's data. In addition to the LIGO detectors, the newly launched Virgo observatory in Italy helped to zero-in on the location of the explosion. They knew that it must be the part of the southern sky which Virgo can not see.

In the hours, days and weeks following the smashup, other forms of light or electromagnetic radiation - including X-ray, ultraviolet, optical, infrared, and radio waves - were detected.

Astronomers around the globe then directed more than 70 space- and ground-based telescopes toward the event for follow-up observations.

The European Southern Observatory, which manages more than a dozen telescopes in the Southern Hemisphere, made significant observations of the August 14 event with "no fewer than 14 different instruments on 10 different telescopes", Tanvir said. Andy Howell, an astronomer from this observatory told The Verge, "This is the reason we all become scientists". "This was entirely unexpected, and our modeling showed that this behavior is due to the jet from the gamma-ray burst being "off-axis" - pointed away from the Earth - a phenomenon we have not seen before". First, that this is the first direct observation of a double neutron star merger, and the observations have confirmed that these events produce elements heavier than lead, including things like platinum and gold. The explosion of neutron stars, which are made nearly entirely of neutrons, was detected by multiple telescopes across the electromagnetic spectrum, from gamma rays and visible light to radio waves. "It is a triumph for the theorists, a confirmation that the LIGO-Virgo events are absolutely real, and an achievement for ESO to have gathered such an astonishing data set on the kilonova". The force of the collision threw materials into the universe, creating stars, galaxies and heavier elements. A single neutron star merger might produce an amount of gold comparable to the total mass of Earth. "It's really a momentous event".

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