2 Neutron Stars Collide, And The Result Is Pure Gold

Scientists have discovered a phenomenon long predicted but never before observed — the collision of two dead stars — and the cosmic crash is shedding light on the mystery of how precious elements such as gold, platinum, silver and uranium, as well as heavy elements like lead, were created. Dinosaurs were still roaming the Earth when the remnants of the dead stars, known as neutron stars, collided, but they weren’t detected until Aug. 17.

The collision set off sensors in space and on Earth, as well as a flurry of research by some 3,500 scientists whose work was published in numerous scientific papers and announced at news conferences held around the world Monday. Scientists have spent decades working on the detection of gravitational waves, and the Aug. 17 event was only the fifth time in history that the ripples have been spotted on Earth. In each of the four previous times, they had been traced to black holes crashing together in far-off galaxies.

Watch: Scientists Witness Huge Cosmic Crash

Scientists say the two dead stars danced around one another for about 11 billion years before they finally merged about 130 million years ago. When they smashed into one another, they flung the elements across the universe in what is known as a kilonova.

It took about 130 million light years for the gravitational waves, first predicted more than a century ago by Albert Einstein in his theory of general relativity, to be seen on Earth.

Einstein theorized that when two neutron stars collide they would produce a gravitational wave, a ripple in the universe-wide fabric of space-time. He also correctly theorized that gamma rays and gravitational waves travel at the same speed, the speed of light, scientists said.

Gamma ray bursts are some of the most energetic and deadly pulses of radiation in the universe. Astronomers weren’t quite sure where short gamma ray bursts came from, but they figured a crash of neutron stars was a good bet. That theory was confirmed in the Aug. 17 event, scientists said.

The signal that sent scientists scrambling was heard as a “chirp” that lasted about 100 seconds, revealing that light and gravitational waves travel at the same speed. Scientists will be able to use the data to measure the rate of expansion in the universe.

“This is a game-changer for astrophysics,” according to University of California, Santa Barbara faculty member Andy Howell, who leads the supernova group at Las Cumbres Observatory. “A hundred years after Einstein theorized gravitational waves, we’ve seen them and traced them back to their source to find an explosion with new physics of the kind we’ve only dreamed about.”

Lauren Cadonati, deputy spokeswoman for the LIGO Scientific Collaboration and a professor in the school of physics at Georgia Tech, said the discovery allows scientists to “fill in a few more tiles in the jigsaw puzzle that is the story of our universe,” according to a report by CNN.

“It’s so beautiful,” said Peter Saulson, a Syracuse University physics professor who has studied gravitational waves for more than 30 years, according to a report by NPR. “It’s so beautiful it makes me want to cry. It’s the fulfillment of dozens, hundreds, thousands of people’s efforts, but it’s also a fulfillment of an idea suddenly becoming real.”

The two neutron stars, both about 12 miles in diameter, were so dense, scientists said, that just a teaspoon of their material on Earth would weigh a billion tons, The Independent reported.

NASA Astrophysics released this animation of the collision and what happened after the big smashup.

The Associated Press contributed to this report.

Video and image courtesy of NASA Astrophysics