APOD: GW170817: A Spectacular Merger Event... (2017 Oct 16)

[Ann]

Thanks, Bruce!

Ann

[RJN]

The APOD text (on NASA's APOD web site) has been updated to indicate that ESA's INTEGRAL observatory also saw prompt gamma-rays, just a few seconds after the gravitational wave signal. We apologize for the oversight.

[BDanielMayfield]

This was and is a great confirmation of expectations as to the site of heavy element production in the universe.

Recipe for making gold, uranium, etc.:

(1) Condense two close orbiting massive stars out of interstellar medium.
(2) Allow cores of two stars to cook light elements up to iron.
(3) Return excess gas and light elements back to interstellar medium via core collapse supernovae, producing binary neutron star pair.
(4) Allow orbital decay to bring two neutron stars into contact, producing kilonova.

Alchemy is easy, if you have enough time and material.

Bruce