February 22
The Red Shoulder
Sun Position
The Sun is in Pisces near +11° declination. Northern hemisphere days approach 11.5 hours; southern days are noticeably shorter than a month ago.
Sky Highlight
No annual event today. Betelgeuse is notable in February because it can be directly compared to Rigel in the same field of view, the color contrast between Betelgeuse's red-orange and Rigel's blue-white is stark even to the naked eye.
Deep Sky Object
M1, a supernova remnant (Crab Nebula) about 6,500 light-years away. The expanding remnant of a supernova observed by Chinese and Arab astronomers in 1054, powered at its center by a pulsar spinning 30 times per second. Visible from both hemispheres; best from northern mid-latitudes in winter.
Featured Star
Betelgeuse (α Ori) is a red supergiant roughly 700 light-years away, spectral class M1-M2Ia-ab, so physically enormous that if placed at the Sun's location it would engulf the inner solar system out to Jupiter. The shoulder of Orion, which will one day become a supernova visible in daylight. We are watching a star die in slow motion.
Around This Date
- February 22, 2019Betelgeuse completed what became known as the Great Dimming, though the full event was documented through late 2019 and early 2020, systematic photometric monitoring in February 2019 set the baseline before the anomalous fading began.
- February 24, 1987Supernova 1987A was observed in the Large Magellanic Cloud, the nearest naked-eye supernova since 1604, its neutrino burst detected hours before its visible brightening.
A star so large it would swallow Jupiter, and yet it sits there, just another point of orange light, if you don't know what to look for.