Popular Astronomy

March 2014

Michael Kinns, observing with his 8'' f6 Orion Optics SPX200 Newtonian reflector, sent in four drawngs this month.                                                                                       

The first, NGC2683, is an edge - on spiral galaxy in the constelation Lynx.  On this occasion, stars as faint as magnitude 13.3 were seen.

NGC2683 is magnitude 9.6, angular dimensions 9.3' x 2.2',  and is considered to be between 16 and 20 million light years from Earth.     



   This drawing is of the globular cluster M2, in the constellation Aquarius.  At 150x,  no individual stars in the cluster were resolved.                                                               


 Michaels third drawing is the open cluster M36, in the constellation Auriga. 

He noted that there were a large number of magnitude 9 - 10 stars in the centre, extending along the spidery arms, and that stars down magnitude 11.5 were visible; the main cluster being elongated N - S.                                            



The final drawing is of galaxy M82, in the constellation of Ursa Major,  and shows the recent supernova:


Dale Holt, using a 505mm (20")  reflector and Watec 120n+ video camera, drew galaxy NGC3081, in the constellation Hydra. 


This is a Seyfert (active) galaxy about 100 million light years away, and is considerd to be one of the best examples of a resonance ring barred spiral known.

Visually, Dale likened it to a planetary nebula with a bright, stellar - illuminated core, with a fainter outer shell of expanding debris.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       

The Section Director re- imaged NGC2392,

 - this time at f10 ( the February 2014 image was taken at f6.3), with the intention of capturing more structural detail.  Small, brght planetary nebulae may respond well to a higher f ratio and thus higher magnification, when employing a sensitive digital camera.  This image was taken with a Meade DSI II Pro mono camera, using Astronomik RGB filters to produce a colour image. Detail right.   



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