In 1987, the nearest supernova seen in nearly four centuries lit up Earth’s skies. Here’s what it looks like today.
“When a star goes supernova, the explosion emits enough light to overshadow an entire solar system, even a galaxy. Such explosions can set off the creation of new stars.” –Todd Nelsen
In 1987, the closest observed supernova to Earth since 1604 occurred, as a supergiant star in the Large Magellanic Cloud exploded.
A wide-field image of the Tarantula Nebula, taken by Hubble, showcases the remnant of Supernova 1987a and its surroundings. Image credit: NASA, ESA, and R. Kirshner (Harvard-Smithsonian Center for Astrophysics and Gordon and Betty Moore Foundation) and P. Challis (Harvard-Smithsonian Center for Astrophysics).
The largest star-forming region in the Local Group, the Tarantula Nebula contains many of the most massive stars in the known Universe, all destined for Type II supernovae.
The first signal seen wasn’t from light, but rather neutrinos, created as the core of the star imploded.
Multiple neutrino events, reconstructed from separate neutrino detectors (akin to Super-Kamiokande, shown here), indicated a supernova’s occurrence before any optical signal ever occurred. Image credit: Super Kamiokande collaboration / Tomasz Barszczak.
Runaway nuclear reactions produce both, but neutrinos pass through the stellar material unimpeded, arriving three hours before the first light signals.
The outward-moving shockwave of material from the 1987 explosion continues to collide with previous ejecta from the formerly massive star, heating and illuminating the material when collisions occur. Image credit: NASA, ESA, and R. Kirshner (Harvard-Smithsonian Center for Astrophysics and Gordon and Betty Moore Foundation) and P. Challis (Harvard-Smithsonian Center for Astrophysics).
The supernova light brightened and then dimmed, but the surrounding gas, blown off from the supergiant, remains illuminated by radiation.
Compact array observations at long wavelengths show that the remnant continues to expand, and the interstellar luminosity continues to rise surrounding the initial explosion. Image credit: Lister Staveley-Smith (UWA), Lewis Ball (ATNF), Bryan Gaensler (USyd), Mike Kesteven (ATNF), Dick Manchester (ATNF) and Tasso Tzioumis (ATNF).
As shockwaves from the explosion move outwards, they collide with interstellar material, producing brightening rings of material.
The two loop-like structures, identified in this Hubble image from five years ago, have taught us a tremendous amount about the final life stages of a pre-supernova star. Image credit: ESA/Hubble & NASA.
Radio observations reveal gas, while X-rays show the peak energies.
A supernova explosion enriches the surrounding interstellar medium with heavy elements. The outer rings are caused by previous ejecta, long before the final explosion. Image credit: ESO / L. Calçada, of the remnant of SN 1987a.
The faint, outer rings teach us that multiple ejection events happened before the final explosion.
This multiwavelength composite sheds light on the behavior of dust (red), visible light (green) and X-rays (blue), which combine to give a complete view of this object that no human eye could see. Image credit: NASA, ESA, and A. Angelich (NRAO/AUI/NSF); Hubble credit: NASA, ESA, and R. Kirshner (Harvard-Smithsonian Center for Astrophysics and Gordon and Betty Moore Foundation); Chandra credit: NASA/CXC/Penn State/K. Frank et al.; ALMA credit: ALMA (ESO/NAOJ/NRAO) and R. Indebetouw (NRAO/AUI/NSF).
Despite being 168,000 light years distant, our great observatories deliver incredible resolution of this remnant.
The closest supernova since the telescope’s invention has enabled improved supernova simulations.
This artist’s impression showcases the cold, inner regions of the remnant, in red, where tremendous amounts of dust were detected and imaged by ALMA. This inner region is contrasted with the outer shell, lacy white and blue circles, where the blast wave from the supernova is colliding with the envelope of gas ejected from the star prior to its powerful detonation. Image credit: ALMA / ESO / NAOJ / NRAO / Alexandra Angelich, NRAO / AUI / NSF.
Energetic gas outflows ensure it will remain luminous for millennia to come.
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