SN 1987A is one of the most well-known and studied supernovae. However, the powerful Webb telescope has now detected strange “crescents” that had not been observed before.
Just 168,000 light-years away, in our galactic neighbor the Large Magellanic Cloud, we find one of the most famous supernovae: SN 1987A. This supernova was discovered in 1987 and has been on astronomers’ favorites list ever since. Thus, it is one of the most famous and studied objects in the night sky. Although the supernova has already been spotted with many telescopes and instruments, now it’s James Webb’s turn. And Webb will never be able to discover something new again.
Mir above SN 1987A
On February 23, 1987, the light of the supernova SN 1987A reached Earth. The explosion occurred at a distance of 168,000 light-years in the so-called Large Magellanic Cloud. It was an unusual explosion for a supernova, especially since it was the closest supernova in nearly 400 years (since the Kepler supernova of 1604). In the case of SN 1987A, a blue-white giant exploded. The diameter of the star was 40 times greater than the diameter of the sun. SN 1987A has reached a magnitude of 2.8, making the celestial body visible to the naked eye in the Southern Hemisphere.
Below is the new image. SN 1987A’s core, a blue region dubbed the “keyhole” by the researchers, is filled with clumps of gas and dust that were forcibly expelled by the explosion. The dust is so thick that not even Webb can penetrate it with his infrared camera. This creates the observable dark “hole” in the centre.
Parelketting
A clear “string of pearls” surrounds the blue area. This is adjacent to two fuzzy arms that extend outward in the shape of an hourglass. The ring was formed from material that was ejected tens of thousands of years before the eruption. The ring contains hot, bright spots – “pearls” – that formed when a supernova shock wave crossed the ring. Remarkably, these spots are now also found outside the ring, with diffuse emission. In these places, the shocks of the supernova come into contact with the outer material.
half moons
Nothing new yet. Many telescopes (such as the Hubble and Spitzer space telescopes) have observed the structures described above. But thanks to Webb’s unparalleled sensitivity, the researchers discovered a surprising new feature of SN 1987A: the presence of tiny “crescents.”
The assumption is that these crescents are part of the outer layers of gas produced by the supernova explosion. Although astronomers don’t quite know what they’re looking at yet. However, they suspect that our angle of view gives the illusion of more material within these crescent-shaped regions than is actually the case.
Clarity and detail
Webb’s new observations provide intriguing new clues about how supernovae evolve over time. This is mainly due to its unprecedentedly high accuracy. The now-retired Spitzer Telescope has observed SN 1987A in infrared nearly its entire life, yielding important insights, but it has never been able to match Webb’s level of resolution and detail.
Despite decades of searching, not all of the mysteries of SN 1987A have been solved. For example, several aspects remain puzzling, including some relating to the neutron star that was supposed to have formed in the aftermath of the explosion. Like Spitzer, Webb will continue to study the famous supernova. Hence hopefully there will be more clarity about the newly discovered strange crescents that harbor the supernova.