February 21
The Dog Before the Dog
Sun Position
The Sun is in Pisces near +11° declination. Northern mid-latitude days are near 11.5 hours; southern autumn is making itself felt in the early sunset.
Sky Highlight
No annual event today. The Winter Triangle (Sirius, Procyon, and Betelgeuse) spans the southern sky on February evenings, one of the most recognizable short asterisms for northern hemisphere observers.
Deep Sky Object
NGC 2683, an edge-on spiral galaxy about 16 million light-years away. A nearly edge-on spiral galaxy in Lynx, nicknamed the 'UFO Galaxy' for its elongated profile, one of the nearer undisturbed edge-on spirals available to amateurs. Best from northern hemisphere mid-latitudes in late winter and spring.
Featured Star
Procyon (α CMi) is a yellow-white subgiant just 11.46 light-years away, spectral class F5IV-V, one of the nearest stars to Earth, paired with a white dwarf companion only separated by about 15 arcseconds. Its name means 'before the dog'. It rises just ahead of Sirius, heralding the brightest star in the sky like a quiet announcement.
Around This Date
- February 21, 1901Nova Persei 1901 was discovered, the first bright nova of the 20th century, flaring to magnitude 0.2 and the first nova subjected to detailed spectroscopic and photometric study.
- February 21, 2008The U.S. Navy used a ship-launched SM-3 missile to destroy the failed spy satellite USA 193 before uncontrolled reentry, the first operational use of a missile defense system against an orbiting spacecraft.
Procyon arrives a few minutes before Sirius every night, sometimes the forerunner matters more than the spectacle.