First Light: Apertura AD8 in search of M101

Tonight was the night I had been waiting weeks for. After so much rain and clouds, finally a clear sky with above average transparency and good seeing. Earlier in the day I double checked the collimation of my Apertura AD8 in preparation for a few late night hours of viewing.

A waxing gibbous moon was about to slip below the horizon so I started taking my gear outside just after 10:00PM to setup in the driveway. My primary objective for the evening was to put the AD8 through its paces and if all went well, see M101 in the process.

The trees in my yard provide me with narrow pockets of open sky so my choice of targets is limited. Tonight, Ursa Major was on center stage. With the scope fully temperature adjusted, I inserted my 30mm 2″ eyepiece, uncapped the finder scope and ran into my first minor problem.

The Orion XT8 I had briefly had a red dot finder (RDF). Although it was difficult for me to use, if aligned properly it was accurate in lining up the scope with a target star I could see in the sky. Put the red dot on the star. Nice and simple.

My Apertura AD8 however is equipped with a Right-Angle-Correct-Image (RADI) finder scope. It is basically a very low power scope bolted to the main scope with a set of crosshairs in the view. What you see in the scope is exactly what you see in the sky, just a very small section at a time (5-degrees). It sounds easy to simply point the finder scope at a star and go but I found it anything but. I ended up needing to use nearby trees as reference points to figure out which star I was looking at in my finder scope! It shouldn’t be that hard. I may have to add a Telrad or build a set of setting circles to overcome this problem.

Using the finder scope I located Mizar, a beautiful example of a Double Star in Ursa Major. It is the star at the bend of the handle of the asterism “Big Dipper”. From there it was easy to follow the line of bright stars (81, 83, 84, 86 UMa) toward M101. Just below 86 UMa is a “belt” of four stars about half the distance to M101. I used the second star from the left in that belt to point almost directly to M101 about a degree away. The reward was the very faint 7.9 magnitude Spiral Galaxy that had been eluding me.

M101 has a very dim surface brightness making it more difficult to see than a similarly rated 7.9 magnitude star. This is because the light from the galaxy is spread over a much larger area (arcseconds or arcminutes). Still, I was able to avert my vision and see it was a fairly large galaxy. I added a 2x Barlow to my 30mm to increase the magnification and I was even able to make out one or two bright stars in one of the spiral arms.

Starhop from Mizar to M101

Starhop from Mizar to M101


Observation log 5/14/2013

Around 11:15 PM I headed out with a goal of seeing one deep space object – M81 also known as Bode’s Nebula a magnitude 6.9 spiral galaxy in the constellation Ursa Major.

I lined up my finder on Dubhe, the tip of the bowl of the Big Dipper and tried star hopping to M81 but I quickly got lost. While I’m sure it can be done, I found a faster way. The star just below Dubhe, h Ursea Majoris is a double with one of the stars being a magnitude 3.65. I easily lined it up in my finder and took my time star hopping up to M81. Any time I got lost, I’d backup to a star or pattern I recognized and retraced my steps. My patience was rewarded when I moved the scope slightly and M81 came into view.

At first, it simply looked like a grey smudge. The more I looked at it, I could see the brighter core. I was using a Celestron 8-24mm Zoom, borrowed off the Library Scope at 24mm for the widest FOV possible. I found that averting my vision, gave the 12 million lightyear (Mly) away galaxy a definite shape.

A slight nudge of the scope and M82 a magnitude 8.4 spiral galaxy came into view. It looks like a vertical fuzzy strip whereas M81 is more of an oval.

At this point I was pleased with myself for having met my goal but decided I wanted to try for one more object on the Messier list. Next was M97 Owl Nebula a magnitude 9.8 planetary nebula also in Ursa Major. Being relatively close to Merak, the bottom front edge of the bowl of the Big Dipper, it took only a few minutes to get within two degrees of M97. Interestingly, I stumbled across M108 a magnitude 10.0 spiral galaxy within about one degree of M97. Like M82, it looks like a vertical fuzzy strip. I expected to see the tell tail “eyes” of the Owl Nebula but couldn’t quite make them out even at 8mm.

It started to get colder so I called it a night.

I have to mention that all of this star hopping and knowing exactly where I was in the sky was due entirely to Sky Safari 3 Pro for iOS. It is an amazing application but my favorite feature is the ability flip the view both horizontally and vertically to match what I’m seeing in my eyepiece. It was trivial and actually fun to hop from star to star, knowing exactly where I was in the sky.

To recap, tonight I saw M81, M82, M97, and M108.

Observations for 5/14/2013