supernova 1987A

supernova 1987A

(SN 1987A) The first naked-eye supernova since 1604 (see Kepler's star). It occurred in the Large Magellanic Cloud (LMC) on Feb. 23 1987, and reached a visual magnitude of 2.9 by May 18 1987. It belonged to the class of type II supernovae, but because its progenitor (Sanduleak –69°202) was a blue supergiant rather than a red supergiant, as is typical for type II supernovae, its peak luminosity was significantly lower and its spectral evolution much more rapid than expected. Initially it was suggested that the unusual color of the progenitor had to do with the lower metallicity of the LMC. However, it now appears more likely that this is a direct consequence of the binary nature of the progenitor system. In this model, the system initially consisted of two massive stars that merged some 30 000 years before the explosion to form a single, but unusual, star at the time of the explosion. This would also help explain the complex nebula surrounding the supernova, detected with the NTT and HST, consisting of three rings (interlocking in projection). The supernova is located at the center of the inner ring (which has a radius of 0.7 light-years). The outer rings are displaced above and below the plane of the inner ring at roughly twice the distance. This material was ejected by the supernova progenitor, presumably as a by-product of the merger event. The supernova blast wave is about to collide with the inner ring and will ultimately destroy it.

The detection of a burst of neutrinos from the supernova has provided direct confirmation of the long-held belief that type II supernovae are triggered by the collapse of stellar cores. In addition, the detection of gamma-ray lines from the radioactive decay of cobalt (56Co), the decay product of nickel (56Ni), to iron (56Fe) has provided evidence for explosive nucleosynthesis, i.e. the synthesis of iron-peak elements and other heavy nuclei during the supernova explosion.

References in periodicals archive ?
Contributing Editor GREG BRYANT has been observing the Tarantula Nebula ever since the adjacent Supernova 1987A burst on the scene.
MeszEiros said his research team's analysis of the less-than-a-dozen recently detected Fast Radio Bursts "supersedes by one to two orders of magnitude the previous best limits on the accuracy of the Einstein Equivalence Principle," which were based on gamma rays and other energies from a 1987 supernova explosion, supernova 1987A.
Caption: Observations of dust (red) detected in the center of the debris from Supernova 1987A suggest that such stellar explosions may be a source of cosmic dust.
An international team of astronomers used ALMA to observe the glowing remains of Supernova 1987A, which is in the Large Magellanic Cloud, a dwarf galaxy orbiting the Milky Way about 160,000 light-years from Earth.
As the discoverer was the man who discovered Supernova 1987a in the LMC, I believed the report to be credible and imaged the field that evening at the reported position, subsequently finding no new object when compared to a POSS1-DSS [Palomar Observatory Sky Survey-Digitized Sky Survey] downloaded image.
2009, "A binary merger model for the formation of the Supernova 1987A Triple-ring Nebula", MNRAS, 399, 515.
1989: Astronomers discover pulsar in remnants of Supernova 1987A (LMC).
FEBRUARY 23 Astronomers observe the first supernova visible to the naked eye since 1604 and call it Supernova 1987a
edu/ photo/cycle1/sn1987a), one in October 1999, the other in January 2000, show the full impact of the blast wave from supernova 1987A (SN1987A).
To understand the complex interactions that occur between a supernova and its local interstellar medium, researchers turned HST's unwavering gaze to the site of Supernova 1987A.
New pictures from the Hubble Space Telescope show that a spot near the exploded star Supernova 1987A has brightened significantly over the past three years.
Detailed images taken from observatories, satellites, and NASA space probes include planets, moons, comets, stars, galaxies, nebulae, Supernova 1987A, quasars, gravitational lenses, and black hole candidates.