A Weather Satellite Uncovers The Mystery of Betelgeuse
A Japanese satellite was accidentally recording the weather on Betelgeuse
The giant star Betelgeuse has long fascinated the inhabitants of our planet. The ancients saw fire and war in its deep red image; its flickering gaze was associated with great predators hunting amongst the heavens. Today the star forms a prominent part of Orion, the Hunter, easily visible on even the brightest of nights.
Yet Betelgeuse is dying. The red colour comes from its cool outer layers. Its inner core now burns helium rather than hydrogen: a step that brings it closer to an inevitable doom. Quite when that end will happen is unknown: in astronomical terms it should be soon; in human terms it may not be for a hundred millennia or more.
Whenever it happens, it promises to be dramatic. Betelgeuse will detonate in a violent supernova; one bright enough to light up the night sky for weeks on end. That possibility has often led to media speculation. When the star unexpectedly dimmed in 2019, the event sparked sensational headlines predicting an imminent supernova.
That, of course, never came to pass. The star eventually brightened again, and now appears much as it has for millennia past. Yet the reason for the dimming — a sudden darkening of the star —…
