The Global Relay of Observatories Watching Transients Happen (GROWTH) program is an international collaborative network of astronomers and telescopes dedicated to the study of short-lived cosmic transients and near-earth asteroids. Cosmic transients are energetic flashes of light that are millions to billions of times the brightness of the sun, e.g. explosive deaths of massive stars, white dwarf detonations, exotic neutron star mergers and tidal disruption by black holes. Key follow-up observations of fast-fading or fast-moving events must occur at night promptly after discovery but before the sun rises. A relay of telescopes spanning multiple longitudes on earth will pass the baton amongst each other to effectively extend the night-time darkness. GROWTH will enable detailed monitoring of events that would otherwise vanish before the next night?s observations could begin at any single location. The torrent of data thus generated shall be used to improve both astronomical observing techniques and big data management and analysis (such as machine learning algorithms, database design and statistics). In addition, the intrinsically international context of the GROWTH program shall foster the development of relationships and social capital required to navigate effectively among diverse science cultures from around the world. Therefore, participating students will have the quantitative, computational and interpersonal skills to assume leadership roles in the knowledge economy.
GROWTH will address several frontier questions in time domain astronomy systematically. GROWTH aims to characterize the electromagnetic emission from binary neutron star mergers, thereby localizing the prime source of gravitational waves expected to be detected by the Advanced Laser Interferometer Gravitational-wave Observatory (LIGO). Timely spectroscopy may identify the long sought cosmic location of heavy element production. GROWTH would track small near-earth asteroids of the type that may pose hazards, to characterize their orbit, size, type and rotation properties. GROWTH shall have a front-row seat to observe the end points of stellar evolution by routinely obtaining data in the first 24 hours of a new-born supernova and directly probing the chemistry and history of the progenitor star. The GROWTH education program will train students and postdocs and encompass undergraduate course development, international internships, annual workshops and a research conference. GROWTH will thus help the US and international community prepare for the era of the Large Synoptic Survey Telescope (starting 2022), NSF's highest priority ground-based astronomy project for the next decade.
