University of Maryland, College Park | 2019 Aug 27
UMD-led team re-examined data from a 2016 gamma-ray burst and found a signature that perfectly matches a gold- and platinum-producing explosion observed by LIGO in 2017.
On August 17, 2017, scientists made history with the first direct observation of a merger between two neutron stars. It was the first cosmic event detected in both gravitational waves and the entire spectrum of light, from gamma rays to radio emissions.In this animated series of images captured by NASA’s Hubble Space Telescope, a newly
confirmed kilonova (red arrow)—a cosmic explosion that creates massive amounts of
gold and platinum—rapidly fades from view as the explosion’s afterglow diminishes over
a period of 10 days. The kilonova was originally identified as a standard gamma-ray burst,
but a UMD-led team of astronomers recently revisited the data and found evidence for
a kilonova. Image credit: NASA/ESA/E. Troja
The impact also created a kilonova -- a turbocharged explosion that instantly forged several hundred planets’ worth of gold and platinum. The observations provided the first compelling evidence that kilonovae produce large quantities of heavy metals, a finding long predicted by theory. Astronomers suspect that all of the gold and platinum on Earth formed as a result of ancient kilonovae created during neutron star collisions.
Based on data from the 2017 event, first spotted by the Laser Interferometer Gravitational-wave Observatory (LIGO), astronomers began to adjust their assumptions of how a kilonova should appear to Earth-bound observers. A team led by Eleonora Troja, an associate research scientist in the University of Maryland’s Department of Astronomy, re-examined data from a gamma-ray burst spotted in August 2016 and found new evidence for a kilonova that went unnoticed during the initial observations.
NASA’s Neil Gehrels Swift Observatory began tracking the 2016 event, named GRB 160821B, minutes after it was detected. The early catch enabled the research team to gather new insights that were missing from the kilonova observations of the LIGO event, which did not begin until nearly 12 hours after the initial collision. ...
The Afterglow and Kilonova of the Short GRB 160821B ~ E. Troja et al
- Monthly Notices of the RAS (online 27 Aug 2019) DOI: 10.1093/mnras/stz2255
- arXiv.org > astro-ph > arXiv:1905.01290 > 03 May 2019 (v1), 26 Aug 2019 (v3)
