Spectacular star merger event detected for the first time - the origin of gold
Illustrative
Video Credit: NASA's Conceptual Imaging Lab.
To watch this video on YouTube: https://www.youtube.com/watch?v=x_Akn8fUBeQ
Both
gravitational and electromagnetic radiations have been detected in rapid
succession for an explosive merging event for the first time.
Data
from the outburst fit well with a spectacular binary neutron-star death-spiral.
The
explosive episode was seen on August 17 in nearby NGC 4993, an elliptical galaxy only
130 million light
years distant.
Gravitational waves were seen first by the
ground based LIGO and Virgo observatories, while seconds
later the Earth-orbiting Fermi observatory
detected gamma-rays, and hours after that Hubble and other
observatories detected light throughout the electromagnetic spectrum.
Pictured
is an animated illustrative movie of
the event's likely progenitors. The video depicts hot neutron stars as they spiral in toward
each other and emit gravitational
radiation.
As they merge, a powerful jet extends that drives the short-duration gamma-ray burst, followed by clouds of ejecta and, over time, an optical supernova-type episode called a kilonova.
This
first coincident detection confirms that LIGO events can be associated
with short-duration
gamma-ray bursts.
Such
powerful neutron star mergers are thought to have seeded
the universe with many heavy nuclei including
the iodine
needed for life and the uranium and plutonium needed for nuclear
fission power.
You
may already own a
souvenir of one of these explosions -- they are also thought to be
the original creators of gold.
