It comes from a supernova seen just 33 years ago, and it doesn’t pulse.
33 years ago, a supernova occurred just 168,000 light-years from Earth.
Dubbed SN 1987A, it was the closest supernova directly observed since 1604.
We first detected the neutrinos from it, and then, hours later, the explosive light.
Originating from the Large Magellanic Cloud, it was briefly visible to human eyes.
For years, scientists examined this cataclysm’s afterglow, observing the bright, expanding gaseous shells.
But inside, embedded within dusty clouds, a remnant core must exist.
SN 1987A was a type II supernova: a blue supergiant exploding at its life cycle’s end.
These explosions always create either neutron stars or black holes, but none had yet been discovered.
Many anticipated a central pulsar’s presence: analogous to the Crab Nebula.
But not all neutron stars pulse; some simply emit high-temperature radiation.
ALMA, a high-resolution radio telescope array, just revealed a telling, critical signature.
ALMA saw a hot “blob” in the dusty center of SN 1987A’s remnant.
It’s located exactly where the observed explosion would “kick” a remnant core.
Black holes can’t heat dust sufficiently; a very young neutron star is required.
It’s the youngest neutron star ever discovered: 33 years old.
As its evolution continues, we may even someday directly see it pulsing.
Mostly Mute Monday tells an astronomical story in images, visuals, and no more than 200 words. Talk less; smile more.Ethan Siegel is the author of Beyond the Galaxy and Treknology. You can pre-order his third book, currently in development: the Encyclopaedia Cosmologica.