Science News: Gravitational waves and telescopes reveal the clash and flash of neutron stars – Producing Gold & Platinum

I found this on a secular science site at https://www.geekwire.com/2017/gravitational-waves-neutron-stars/ This is not a general endorsement of the site.

Excerpts:

For the first time ever, researchers have recorded the cataclysmic smash-up of two neutron stars by virtue of their gravitational waves as well as their electromagnetic emissions, producing data that could unlock cosmic secrets galore.

The findings from the Aug. 17 event, detailed today in more than a dozen research papers, represent the best example of “multi-messenger astronomy.”

More than 70 observatories and thousands of scientists contributed to the findings, headed by the Laser Interferometer Gravitational-wave Observatory, or LIGO.

“We did it again — but this time, we all did it,” David Reitze, executive director of the LIGO Laboratory, said at today’s news briefing announcing the results.

By combining the gravitational-wave readings with observations in wavelengths ranging from radio signals to gamma rays, scientists are gaining new insights into how neutron stars evolve, and how gold and other heavy elements are forged in their furnaces.

Neutron stars are leftovers from stellar explosions, consisting of exotic matter that has been crushed so densely that a teaspoon’s worth would weigh millions of tons. They’re typically no more than 12 miles wide, but are more massive than the sun.

The buildup to a neutron star merger had never been observed before. But scientists previously suspected that at least some gamma-ray bursts were caused by neutron star smash-ups, and the LIGO data fit the models. The gravitational-wave pattern pointed to the merger of two stars, 1.1 and 1.6 times as massive as the sun, at a distance of 130 million light-years from Earth.

The all-points bulletin for astronomical observations quickly produced paydirt. Within hours, astronomers using the Carnegie Observatories’ Swope Telescope in Chile reported seeing an optical counterpart to the gamma-ray flash and the gravitational-wave crash in a galaxy called NGC 4993. That narrowed down the target to a precise spot.

For almost two months now, astronomers have been monitoring the spot in wavelengths ranging from radio and infrared to X-rays and gamma rays. The readings consistently point to a neutron star merger as the cause of the event on the morning of Aug. 17.

“The detection of gravitational waves from a binary neutron star is something that we have spent decades preparing for,” Alan Weinstein, head of Caltech’s astrophysical data analysis group for LIGO, said in a news release. “On that morning, all of our dreams came true.”

Follow-up studies have confirmed long-held suspicions that such collisions create heavy elements, including some that are essential for life, and spread them into the wider cosmos. The evidence is contained in spectral signatures of chemical elements that have been seen in infrared observations of the blast site.

“For the very first time, we see unequivocal evidence of a cosmic mine that is forging about 10,000 Earth-masses of heavy elements such as gold, platinum and neodymium,” said Caltech’s Mansi Kasliwal, leader of a 18-telescope network known as the Global Relay of Observatories Watching Transients Happen, or GROWTH.

Here’s another video the site pointed to that adds further scientific background that is easy enough to understand for the common man.