BETA (β) CYGNI
CONTRAST OPTICAL DOUBLE STAR
Right Ascension:
19h 30m 43s
Best Seen:
6/15 - 11/15
Declination:
27º 57' 35"
Combined
Magnitude:
3.05
Computer File:
betacyg
Constellation:
Cygnus
Apparent
Separation:
34.4"
Actual
Compared to Sun
Distance
385 / 376 l.y.
--
Actual Brightness
--
497 / 94
App.Magnitude
3.08 / 5.12
--
Abs. Mag
-2.2/-0.2
Mass
--
~4Msun /~6Msun
Size
~20Rsun /~3Rsun
Surface Gravity
--
--
Surface Composition (by mass)
74% hydrogen 24% helium 2% everything else
same
Spectral Type
K3 II / B8 Ve
G2 V
Density (gram/cubic cm)
--
--
WHAT TO LOOK FOR THROUGH THE TELESCOPE:
-
Recommended eyepiece: 24mm or 40 mm.
-
When people look through the telescope they should see two stars next to each other. The brighter star should appear yellow and the dimmer star blue.
BETA CYGNI INFORMATION:
-
This star is also known as Albireo. It is one of the best known contrast optical double stars.
-
The yellow star is actually a multiple star system: the star and an unseen companion orbit each other.
Item
Updated
Notes
Coordinates
07-24-2002
SIMBAD, The Flamsteed Collection
Combined Magnitude
07-24-2002
with Scott’s The Flamsteed Collection
Apparent Separation
07-24-2002
http://www.astronomical.org/constellations/cyg.html
Distance
Actual Brightness
Magnitude
07-24-2002
with Scott’s Starlist 2000
Mass
Surface Gravity
Surface Composition
01-06-2003
OK for all stars
Spectral Type
07-24-2002
SIMBAD
Density
Other Information
Size, Mass
07-24-2002
05-04-2005
1. previous: “About 60 of our solar
systems could be laid edge to
edge between these two stars.”
– BUT much more, so took out.
2. added info about binary
found at http://www.daviddarling.info/encyclopedia/A/Albireo.html Other data found using app.mag, dist. and spectral class on a graph of the HR diagram