July 22
Two Thousand Six Hundred Light-Years
Sun Position
The Sun enters Leo on approximately July 22–23, at about +20.4° declination. Northern Hemisphere summer; Southern Hemisphere winter. Leo is behind the Sun and not observable; the evening sky shows Cygnus rising in the east.
Sky Highlight
No named meteor shower peaks on July 22. The Sun's entry into Leo marks a traditional milestone in the Northern Hemisphere summer. Cygnus is well-placed overhead at midnight from mid-northern latitudes, making this a fine week for sweeping the Cygnus Milky Way with binoculars. From the Southern Hemisphere, Cygnus is low but accessible with a clear northern horizon.
Deep Sky Object
NGC 7027, a compact planetary nebula in Cygnus roughly 3,000 light-years away. It is one of the youngest and most physically small planetary nebulae known, with a very hot central star and a high surface brightness that makes it detectable even in small telescopes as a faint but distinct cyan-green point. Best from the Northern Hemisphere.
Featured Star
Deneb (α Cyg) is a blue-white supergiant roughly 2,600 light-years away in Cygnus, classified A2Ia, one of the most luminous stars visible to the naked eye. If Deneb were at the same distance as Vega (25 light-years), it would cast shadows at night. Its exact distance is uncertain; 2,600 light-years is the commonly used estimate.
Around This Date
- July 22, 1951Soviet space dogs Dezik and Tsygan were launched on a suborbital flight from Kapustin Yar, becoming the first dogs to fly in space and the first to return safely, preceding Laika's orbital flight by six years.
- July 22, 1959Plan 9 from Outer Space, directed by Ed Wood and featuring Bela Lugosi, received its wide American theatrical release, a film so earnestly inept in its depiction of alien resurrection that it eventually became the definitive cult classic of bad science fiction cinema.
Deneb's light has been traveling since before the Byzantine Empire fell, and it arrives tonight looking perfectly fresh.