Urban Program - Double and Variable Stars List



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There are actually two lists, one for deep-sky objects, and this one for double and variable stars. All objects are listed in Right Ascension order so that you can view them as they rise in the East and set in the West. Information provided on double and variable stars includes: Object, Right Ascension, Declination, Magnitude, and Separation of the components.

For a printable version of this list, click here

The Urban Program - Double and Multiple Stars
Object Name Right Ascension Declination Magnitude (Range) Separation
Eta Cassiopeia 00h 49.1m +57° 49' 3.4, 7.5 12"
Gamma Aries 01h 53.5m +19° 18' 4.8, 4.8 7.8"
Gamma Andromeda 02h 03.9m +42° 20' 2.3, 5.5 9.8"
Trapezium 05h 35.3m -05° 23' 6.7, 7.9,
5.1, 6.7
8.8", 13", 21.5"
Beta Monoceros 06h 28.8m -07° 02' 4.7, 5.2 7.3"
Gamma Leo 10h 20.0m +19° 51' 2.2, 3.5 4.4"
Zeta Ursa Major 13h 23.9m +54° 56' 2.3, 4.0, 4.0 14.4, 709"
Beta Scorpius 16h 05.4m -19° 48' 2.6, 4.9 13.6"
Epsilon Lyra 18h 44.3m +39° 40' 5.0, 6.1, 5.2, 5.5 208", 2.6", 2.3"
Beta Cygnus 19h 30.7m +27° 58' 3.1, 5.1 34.4"
Gamma Delphinus 20h 46.7m +16° 07' 4.5, 5.5 9.6"
Delta Cepheus 22h 29.2m +58° 25' 3.9, 6.3 41"


The Urban Program - Variable Star

Object Name Right Ascension Declination Magnitude (Range) Separation
Beta Perseus (Algol) 03h 08.2m +40° 57' 2.1-3.4 Variable
(2.9 days)
  1. Determine the dates and times of upcoming Algol minima.
  2. Observe naked-eye and estimate the star's brightness during a minimum by comparing it to nearby stars.
  3. Repeat the observation and estimate Algol's brightness on any non-minima night.

Sky & Telescope Magazine’s Minima of Algol column can be found in each monthly issue.  Locate “Celestial Calendar” in the “Observing” section of each issue’s “Table of Contents”.   While the Minima predictions are generally not listed in the Table of Contents, they are usually located just a page or two from the first “Celestial Calendar” page.

You can also find them on the Sky & Telescope Websitehttps://skyandtelescope.org/observing/the-minima-of-algol/  
Page down about ½ way until you see the “Initialize to Today” button.  Click it and quickly see the appropriate results.

A finder chart can be printed here:

Use any convenient star chart or planetarium program to determine the magnitudes of neighboring stars, or use:

α Persei 1.8 (alpha Persei)
ζ Persei 2.8 (zeta Persei)
ο Persei 3.8 (omicron Persei)

More information about variable star observing can be found at: http://www.astroleague.org/al/obsclubs/variablestar/VSOIntroduction.html

Related Links

Urban Program Introducttion
Urban Program - Deep Sky Objects
Urban Program - Tips for Observing in Light Polluted Areas
Find Your Urban Program Award