Posted on by Nancy Atkinson

A Kilonova Simulated in 3D

An artists impression of a kilonova, the moment where two neutron stars merge. Credit: Dana Berry, Skyworks Digital, Inc.

In 2017, astronomers detected gravitational waves from colliding neutron stars for the first time: a kilonova. Enormous amounts of heavy metals were detected in the light from the explosion, and astronomers continued to watch the expanding debris cloud.

Researchers have continued to study this event. Now, using a three-dimensional computer simulation, they have created a new recreation of this merger — second by second, as it happened — giving insights into all the high-energy mayhem and heavy elements formation in this catastrophic event.

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Posted on by Nancy Atkinson

After Decades of Observations, Astronomers have Finally Sensed the Pervasive Background Hum of Merging Supermassive Black Holes

In this artist’s interpretation, a pair of supermassive black holes (top left) emits gravitational waves that ripple through the fabric of space-time. Those gravitational waves compress and stretch the paths of radio waves emitted by pulsars (white). Aurore Simonnet for the NANOGrav Collaboration

We’ve become familiar with LIGO/VIRGO’s detections of colliding black holes and neutron stars that create gravitational waves, or ripples in the fabric of space-time. However, the mergers between supermassive black holes – billions of times the mass of the Sun — generate gravitational waves too long to register with these instruments.

But now, after decades of careful observations, astronomers around the world using a different type of gravitational wave detection method have finally gathered enough data to measure what is essentially a gravitational wave background hum of the Universe, mostly from supermassive black holes spiraling toward collision.  

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