Free Astronomy Magazine January-February 2020

21 JANUARY-FEBRUARY 2020 SPACE CHRONICLES sitting in a very dense environment, right in the middle of a bright galaxy 5 billion light years away,” explained one of the lead authors, Andrew Levan of the Institute for Mathemat- ics, Astrophysics & Particle Physics Department of Astrophysics at Rad- boud University in the Netherlands. “This is really unusual, and suggests that might be why it produced this exceptionally powerful light.” Astronomers used the NASA/ESA Hubble Space Teleescope, together with the European Southern Obser- vatory's Very Large Telescope and the Atacama Large Milimeter/sub- milimeter Array to study the host galaxy of this GRB. Hubble's Wide Field Camera 3 was instrumental in studying whether the environmental properties of the host system, which is composed of a close pair of inter- acting galaxies, might have con- tributed to the production of these very-high-energy photons. The GRB occurred within the nuclear region of a massive galaxy, a location that is rather unique. This is indicative of a denser environment than that in which GRBs are typically observed and could have been crucial for the generation of the very-high-energy photons that were observed. “Scientists have been trying to observe very-high-energy emission from gamma-ray bursts for a long time,” explained lead author Anto- nio de Ugarte Postigo of the Instituto de Astrofísica de Andalucía in Spain. “This new observation is a vital step forward in our understanding of gamma-ray bursts, their immed- iate surroundings, and just howmat- ter behaves when it is moving at 99.999% of the speed of light.” G RB 190114C according to an artist’s impression. [ESA/Hubble, M. Kornmesser] !