M35: Open Cluster in Gemini

  Catalogues M35; NGC 2168
  Names Open cluster in Gemini
  Type Globular Cluster
  Constellation Auriga
  Season Visible in Evening Winter; November - April
  Conversation Notes Large bright open cluster in Gemini. Several hundred stars - around a hundred visible in a small scope. Compare to the nearby M37 and M38.

Open clusters are easy to find and observe in small telescopes, pretty, and scientifically important. This is a group of stars all born from a common cloud of gas and dust. Since they came from the same gas cloud they are, astronomically speaking, all about the same age and all about the same distance from us. Knowing that they are the same age and at the same distance, the fact that they have different appearances allows us to learn a great deal about stellar evolution - the different appearances can only be a result of the different masses of the different stars.

Finding M35

Like many of the other winter open clusters, start by finding Orion in the southern sky. Orion is easy to find by looking for his distinctive 3-star belt. Constellation Orion in southern winter sky
Study Orion and the area around him for a moment. Star field around Orion
Note the distance between his left foot and his left shoulder - we will use that as a measure. Orion, highlighting the distance from his left foot to his left shoulder
Mentally extend that line in the same direction, the same distance. Orion, showing line from foot to shoulder extended in the same direction
Note that you end up just above and to the right of a pair of dim stars. (These are part of the foot of Castor, one of the Gemini twins.) Area above Orion, showing the extended measure line and circling 2 stars in Castor's foot
Point your telescope to the left of the end of your imaginary line. The distance to the left is about the same as the distance between two stars in Orion's belt. Area above Orion, showing scope pointed between reference line and Castor's foot

Go back to the picture with no lines, above, and do this mental test yourself, then compare your results to this target.

Star field above Orion, without lines, to practice finding M35

In your magnifying finder, you will find M35 as a small fuzzy patch of light.

(If you don't have a magnifying finder, hunt around with your telescope, with your lowest-power, widest-field eyepiece.)

M35 in an 8x50 finder scope

This simulation shows the appearance of this cluster in a 100 mm refractor with dark skies, at about 35x magnification. Note the interesting internal structures that the density and location of the stars seem to trace out.

Image of M35 in telescope at about 30x magnification.

All the above images were generated with Stellarium and Starry Night Pro.


 
  135  accesses changed Feb 23, 2008
 
 
Copyright © 2008 Richard McDonald