Category: double

Almach (Gamma Andromedae) a colorful double star
Sketch and Details by Sebastian Lehner

Almach – Colorful Double

Object Name: Gamma Andromedae, Almach
Object Type: Double Star
Location: Erbendorf, Bavaria
Date: July 22nd 2007

The double star system Gamma Andromedae – or Almach – as it is also
called, is always worth a visit, when it is riding high in the sky
during long autumn nights. The couple provides a wonderfully rich color
contrast with the main component glowing in a golden-orange and the
smaller component in a blue-green color. The two stars, which are 350
light years away, are seperated by approximately 10 arcseconds and
can thus be easily viewed even with smaller telescopes.

The drawing was made with pencils on white paper, then scanned and
processed digitally in photoshop.

The telescope used was a TAL 6″ f/5 Newtonian on a Vixen GP mount.

Sebastian

Xi Bootes, Double Star
Sketch and Details by Math Heijen

On the evening of May 9th 2008 I observed a series of double stars in Bootes. The highlight for me that night was Xi Bootes. This colorful double lies about 8 degrees east of Arcturus. The Yellow primary star shines at magnitude 4.8 and it’s magnitude 7.6 orange companion lies at a position angle of 315°. The separation is 6.3″. Through the 17mm Nagler the double looks fairly close (scale from “Double Stars for small Telescopes” by Sissy Haas). When looking at Xi Bootes through the 17mm Nagler, the double seems to be part of an asterism that looks like the constellation Cygnus, only much smaller. Xi Bootes is placed at the position of Deneb, the tail of the swan. We decided to call the asterism “Little Cygnus”. On the sketch below the asterism is oriented West-East. At the tail you find Xi Bootes. Three white stars oriented north-south represent the wings of the little swan. A white star to the east (accompanied by a dimmer companion) is at the position of the head of the swan. The yellow star to the eastern edge of the field of view is just a bright field star. It is no part of the “Little Cygnus” asterism.

The sketch of “Little Cygnus ” and Xi Bootes was made using the 300mm f/5.3 Dobson and a 17mm Type4 Nagler. The magnification is 94x and the field of view is 52′. At the telescope I made a sketch on white paper using a HB led-pencil. This sketch was scanned and processed in Photoshop. I colored the double star (and the field star to the east) using the tutorial described on the website of Jeremy Perez ( http://www.perezmedia.net/beltofvenus ). This is the first time I experimented with this technique, and I am very pleased with the result. It produces a realistic image and resembles what you see through the eyepiece. In the future I will try to use this technique for sketching more double and multiple stars.

29 Aquarii, An Easy Double
Sketch and Details by Wade V. Corbei

29 Aquarii (DX Aqr, 29 Aqr, HR 8396) is a nice equal magnitude double star located in the constellation Aquarius. This is an easy split at around 150x, but at higher magnifications there is an apparent color contrast between the two. The primary displays as a whitish/blue and the secondary shows an obvious orange (the secondary is actually classified as an Orange Supergiant).

A nice easy double for those interested in double stars that can be cleanly split without excessive magnifications, and this double pretty much sits alone in the sky with very few background stars in the same field of view.