SN 1987A was a colossal stellar explosion, a type II supernova, in the Large Magellanic Cloud, a dwarf satellite galaxy of our Milky Way. It occurred roughly 168,000 light-years from Earth and was the closest observed supernova since Kepler’s Supernova in 1604.
The explosion was first detected on February 23, 1987, by both optical telescopes and neutrino detectors. The neutrinos arrived first, a mere 3 hours before the light reached Earth, providing the earliest-ever warning of a supernova. SN 1987A became the most studied supernova in history due to its relative closeness and early detection.
The supernova was the result of a supergiant star collapsing and exploding, and it was special since its parent star had been seen and identified before it happened. Supernova theory saw significant advancements as a result of the supergiant’s higher temperature than anticipated for an immediate progenitor.
Earth saw the detection of a neutrino burst that coincided with the star’s death, confirming theoretical predictions about nuclear processes that take place during supernovas. The neutron star left behind by the supernova explosion was discovered in 2024 by the James Webb Space Telescope as a result of ongoing research into the developing remnant into the twenty-first century.
Image taken with Hubble‘s Wide Field and Planetary Camera 2in 1995, shows the orange-red rings surrounding Supernova 1987A in the Large Magellanic Cloud. The glowing debris of the supernova explosion, which occurred in February 1987, is at the center of the inner ring. The small white square indicates the location of the STIS aperture used for the new far-ultraviolet observation.
Here are some key aspects of SN 1987A:
Type II Supernova:
It is classified as a core-collapse supernova, a type that occurs when a massive star runs out of fuel and its core can no longer support its own weight. The core implodes, triggering a powerful explosion that blasts the star’s outer layers into space.
Birth of a Neutron Star:
According to the prevailing theory, the core collapse of the progenitor star in SN 1987A should have resulted in the formation of a neutron star. However, despite extensive searches, astronomers weren’t able to definitively identify the neutron star until 2024, when JWST discovered it.
Expanding Remnant:
The blast wave from the explosion continues to expand, illuminating and shaping the surrounding gas and dust.
What is a Supergiant Star?
A supergiant star is any star that has a very high intrinsic brightness and is quite large; they are usually many times larger in diameter and several magnitudes brighter than giant stars. In practice, the differences between giants, supergiants, and other classifications are determined by analyzing certain spectra lines.
Supergiant stars can have diameters several hundred times larger than the Sun and luminosities close to one million times that of the Sun. Supergiants are unstable stars with very limited lifespans compared to other star types, perhaps lasting only a few million years.
What is a Supernova?
Supernovae are the result of a massive star’s explosive explosion when its nuclear fuel runs out after millions to billions of years of fusion events. A massive star that is nearing the end of its life will collapse due to gravity, resulting in an explosion that will be visible for weeks or perhaps months, brightening whole galaxies. Depending on the mass and evolutionary stage of the progenitor star, different physics leads to different supernova explosions.
Conclusion:
SN 1987A has provided astronomers with a wealth of information about the physics of supernovae and the life cycle of massive stars. The ongoing study of this exceptional supernova continues to shed light on these spectacular stellar explosions around the universe.