Trapezium with 6 members resolved

Trapezium with 6 members resolved – 2013-04-01

The four brightest stars in the image above form the “Trapezium” – a well known multiple star system in the Orion nebula and known collectively as Theta Orionis. There are many more stars in the group and this image picks up the standard 4 as well as 5th and 6th brightest members – mag 10.2/10.3.

The 10 brightest stars in the multiple system are:
A – 6.7-7.5 variable
B – 8.0-8.5 eclipsing binary
C – 5.1
D – 6.7
E – 10.3
F – 10.2
G – 14.4
H1 – 14.5
H2 – 15.5
I – 15.0

The tear drop shaped stars is due to atmospheric dispersion as Orion was relatively low on the horizon. The differing density as the air gets thicker near the horizon cause a point of light to spread out.

The image is stretched quite a bit with heavy use of wavelets to shapen the details and bring out the two fainter stars.

Image Details:
HD11, 5x PowerMate, Pont Grey Chameleon at 640x480pix, 0.11arc-sec/pixel
1min 16sec uncompressed AVI at 3fps, 0 gain. (250 frames)
Stacked with Registax
Processed with PixInsight