w1800 20190827 Albireo A7Ra ISO3200 3x30s

The Albireo system is a double star designated Beta Cygni (β Cygni, abbreviated Beta Cyg, β Cyg). The International Astronomical Union uses the name "Albireo" specifically for the brightest star in the system. Although designated 'beta', it is fainter than Gamma Cygni, Delta Cygni, and Epsilon Cygni and is the fifth-brightest point of light in the constellation of Cygnus. Appearing to the naked eye to be a single star of magnitude 3, viewing through even a low-magnification telescope resolves it into its two components. The brighter yellow star (actually itself a very close binary system) makes a striking colour contrast with its fainter blue companion.

Beta Cygni is about 415 light-years (127 pc) away from the Sun. When viewed with the naked eye, Albireo appears to be a single star. However, in a telescope it resolves into a double star consisting of β Cygni A (amber, apparent magnitude 3.1), and β Cygni B (blue-green, apparent magnitude 5.1). Separated by 35 seconds of arc, the two components provide one of the best contrasting double stars in the sky due to their different colors.

ObjectAlbireo Duo Star
Constellation: Cygnus
Position: RA 19h 30m 43.286s  DEC +27° 57′ 34.84″
Apparent Size:  
Apparent Magnitude Cygni A +3.18 and Cygni B +5.1
Distance (average) 430 ly
Photo Datas 
Date 27.08.2019, 21:43 UTC
Location Knottenried/Oberallgäu, 1002m ASL
GPS: 47°36’13“ N, 10°11’24“ E
Sky darkness SQM-L Zenit 21.00 mag/sqrsec, Object 21.05 mag/sqrsec
Ground Temp./Air Pressure 18.5°C /1016mbar
Thermal sky temp./weather  -27.0°C Zenit / high altitude haze
Seeing  4/10 
Telescope TS RC 14" 2845mm f/8.0
Camera Sony A7Ra mod @ T sensor=21.6°C !!
Expose frames ISO 3200, RAW 12x30s, 16 darks
Total expose
6 min.
Filter no
Mount HPS 10Micron GM 3000
Guiding Cam no
Software DSS 3.3.4, Photoshop CC
Remarks Corona by high altitude haze

C 2019 Peter Cerveny