September 20
The Queen's Light
Sun Position
The Sun is in Virgo at about -4° declination, two or three days before the autumnal equinox. Night is now measurably longer than day across the Northern Hemisphere; Southern Hemisphere spring gains momentum.
Sky Highlight
The autumnal equinox falls on approximately September 22–23. In the days approaching it, Cassiopeia is rising high in the northeast at nightfall, and Perseus is ascending behind it, making this one of the best weeks for the northern sky's autumn survey. No major annual meteor shower peaks today.
Deep Sky Object
NGC 457, Owl (or ET) Cluster, Cassiopeia. An open cluster about 7,900 light-years away, with roughly 80 confirmed members and two bright supergiants that give it the appearance of a large figure with glowing eyes. Circumpolar for observers north of about 40°N; low but visible from mid-southern latitudes.
Featured Star
Schedar (α Cas) is an orange giant of spectral type K0IIIa, about 228 light-years away, the brightest star in Cassiopeia by conventional magnitude. It is a mild semi-regular variable, fluctuating by a few tenths of a magnitude over a loosely periodic cycle, and its orange hue is visible without optical aid under good conditions.
Around This Date
- September 20, 1945Over 100 German rocket scientists arrived at Fort Bliss, Texas, as part of Operation Paperclip, bringing expertise that would later directly inform the Redstone and Saturn rocket programs.
- September 23, 1846Johann Galle and Heinrich d'Arrest at the Berlin Observatory discovered Neptune, the first planet located through mathematical prediction rather than direct observation.
Schedar's orange light is cool and steady above the northern horizon, a queen's beacon that circumpolar observers can count on every clear night of the year.