2011

First public test of the observatory


This was the first public test of the improved observatory.  A total of 14 people, mainly from the physics department, attended the session.

The session started early, before the sky was completely dark, to make sure that Saturn would still be above the horizon. At 9pm, Saturn was less than 10 degrees above the horizon and its image was severely affected by the atmosphere. The rings were obvious, but no sign of the Cassini division.

Then we observed Albireo, a double star showing a nice colour contrast. One is blue and the other is orange. The blue star has a surface temperature of roughly 30,000K while the orange one is close to 5,000K. Both of them are separated by about 1,000 A.U.

The next object was Messier 57, the ring nebula. It is my favorite planetary nebula. It is relatively easy to observe in a light polluted sky. Even for first time astronomers, it was easy to recognize as a strange doughnut shaped object.

Most people left by that time, but we continued with Messier 13, the Hercules globular cluster, a gorgeous ball of several 100,000 of stars. Many of them can be resolved. I believe that object generated the loudest “wow”.

After that, we looked at the 94% illuminated Moon that was rising. It was low on the horizon but the resolution at the eyepiece was surprisingly good!

Finally, I started to look into the polar alignment of the mount. This is done almost entirely by the go-to remote controller for the CGE Pro mount. It was relatively easy to perform, but the azimuth fine adjustment didn’t travel far enough to get a very precise alignment. We will have to rotate the pier a little bit. Nevertheless, the tracking was improved and star trails only appear after 20-30 seconds. This is very good for a 3910mm focal length telescope.

After trying to save time by not recalibrating the mount, and about 2 hours of looking around for objects without finding them, we decided to try the Pinpoint software to try to match-up the star on an image to an internal database. It worked about 20% of the time and with its help we were able to find again Messier 57. At that time it was late and we recorded 3 pictures. One with a red filter, one with a green filter and the other with a blue filter. Each one was 20 seconds long. Then we recombined all 3 images into a colour image and it gave this reasonable picture of the nebula. The inner green section is due to doubly ionized oxygen at around 500nm. The surrounding red ring is visible because of the Hydrogen 656nm transition.  In the very center, there's a very dim white dwarf star. When we observe Messier 57 with our eyes, it is mainly black and white (or blue and white) because our dim light sensitive rods in our eyes are not sensitive to colours.

M57 - RGB