Possible Sign of Neutron Star Found in Supernova 1987A
July 31, 20204 minutes
Two teams of astronomers, including Department of Physics and Astronomy’s James M. Lattimer, distinguished professor of astronomy, have made a compelling case in the 33-year-old mystery surrounding Supernova 1987A (SN 1987A). Based on observations of the Atacama Large Millimeter/submillimeter Array (ALMA) and a theoretical follow-up study, the scientists provide new insight for the argument that a neutron star is hiding deep inside the remains of the exploded star. This would be the youngest neutron star known to date.
Ever since astronomers witnessed one of the brightest explosions of a star in the night sky, creating Supernova 1987A, they have been searching for a compact object that should have formed in the leftovers from the blast.
Because particles known as neutrinos were detected on Earth on the day of the explosion, February 23, 1987, astronomers expected that a neutron star had formed in the collapsed center of the star. But when scientists could not find any evidence for that star, they started to wonder whether it subsequently collapsed into a black hole instead. For decades the scientific community has been eagerly awaiting a signal from this object that has been hiding behind a very thick cloud of dust.
“The neutron star behaves exactly like we expected,” said Lattimer, who has followed SN 1987A closely, having published prior to SN 1987A predictions of a supernova’s neutrino signal that subsequently matched the observations. “Those neutrinos suggested that a black hole never formed, and moreover it seems difficult for a black hole to explain the observed brightness of the blob. We compared all possibilities and concluded that a hot neutron star is the most likely explanation.”
Lattimer is grateful to the U.S. Department of Energy for funding his research on supernovae and neutron stars over the years.
The Atacama Large Millimeter/submillimeter Array (ALMA), an international astronomy facility, is a partnership of the European Organisation for Astronomical Research in the Southern Hemisphere (ESO), the U.S. National Science Foundation (NSF) and the National Institutes of Natural Sciences (NINS) of Japan in cooperation with the Republic of Chile. ALMA is funded by ESO on behalf of its Member States, by NSF in cooperation with the National Research Council of Canada (NRC) and the Ministry of Science and Technology (MOST) and by NINS in cooperation with the Academia Sinica (AS) in Taiwan and the Korea Astronomy and Space Science Institute (KASI).
ALMA construction and operations are led by ESO on behalf of its Member States; by the National Radio Astronomy Observatory (NRAO), managed by Associated Universities, Inc. (AUI), on behalf of North America; and by the National Astronomical Observatory of Japan (NAOJ) on behalf of East Asia. The Joint ALMA Observatory (JAO) provides the unified leadership and management of the construction, commissioning and operation of ALMA.