M3 – Globular Cluster


Messier 3 is a globular cluster in the constellation Canes Venatici at a distance of 33,900 light-years away from Earth with a magnitude of 6.2. It is one of the largest and brightest globular clusters visible in the northern hemisphere, and consists of around 500,000 stars. Globular clusters are groups of old stars with this cluster being estimated at 8 billion years old. Within this cluster are a known 274 variable stars – the most found within any globular cluster.
‘X’ marks the location of M3.
I happened to be out viewing this cluster as the moon was already beyond 50% so it was washing out a lot of the stars, galaxies, and nebula in the sky. I decided on M3 as it is one of the brightest globulars, and it was one of the few that was above my tree line from the backyard. Considering the moon brightness paired with light pollution I was very impressed with the view of it through the telescope, and of course couldn’t resist getting a few images of it to stack and show off.
Given it’s location along the border of 3 constellations; Canes Venatici, Bootes, and Coma Berenices it wasn’t the easiest to find due to it’s location in the sky and it’s lack of many stars visible to guide from. This was the first time I actually used my RA and DEC dials on my EQ mount. Using the star Arcturus as my setting star I tried it a few times with success on each attempt making M3 land within the view each time.
M3 Globular Cluster in Canes Venatici. April 2, 2012. Also above the cluster is Galaxy NGC 5263 at magnitude 14.
This consists of 14 images at 30 seconds a piece, 10 dark frames and 20 bias frames taken on April 2, 2012. Since the temperature at night has been the same during the last few sessions I’m able to reuse the same darks, and bias frames each time. I planned on getting a few more dark frames while I was out, but I had some difficulties with my polar alignment and tracking that I was getting a lot of star trails. By the time I finally got everything the way I needed it to be I was almost out of battery on my camera.

April 6, 2011 Viewing Session

Went out for a short viewing session last night, sorry no pictures for this one. I had originally planned only to go out to check out my collimation of the telescope mirrors. In short collimation is a precise alignment of the telescopes optics. For doing it by eye I’m pretty close. Not right on but for my first time it’s close and I’m happy with it.

After I did my star test on Arcturus to make sure the collimation was on I decided to go up to globular cluster M3, which is East of Arcturus (a bit higher up in the sky when looking towards Arcturus). M3 was a fuzzy ball of stars in my eyepiece, pretty sight to see, would probably be a bit more detailed of a view if I didn’t have as much light pollution as I do, especially looking directly over a street light.

Once I was done focusing in on M3 I decided to see if I could see the Great Cluster in Hercules, M13. M13 is a bit brighter than M3; M13 being a magnitude 5.9, and M3 being a magnitude of 6.4. The lower the number the brighter the object, some objects are a negative number (ie: Sun -26.7, Moon -12, Venus at it’s brightest is -4.7, and the brightest star Sirius is -1.5). While viewing this Great Cluster in Hercules in my 12.5mm eyepiece to have it fill in the view of the globular prettiness. It was a bit fuzzy, maybe the collimation is still a tad off? But while looking at it all of a sudden I saw a white light float by my view of it. I just kind of sat there in awe thinking to myself that I just accidentally saw a satellite float by my eyes. So I quickly rushed in to look on Stellarium to see what the satellite may have been, but there was no signs of one when I looked for it. May have been an amateur satellite, I doubt it was a meteor or anything like that, it went by pretty slowly in the eyepiece at a magnification of 80x.

I swung over towards the West and found the constellation Cancer, in Cancer there is Praesepe, M44. I kind of found it by luck seeing as where I’m viewing from the lights make it hard to make out the dimmer stars, and I don’t know if it’s just me, but Cancer is a bit dim, so it made it hard to spot. I used a star in the head of Leo and Pollux in Gemini to help get me in the rough area to point. I found Praesepe in my 32mm and because of it’s size since it’s an open cluster I decided to not try and magnify it.

I also, again, viewed Saturn. I’m pretty sure I’m going to be viewing Saturn EVERY time I go outside now, at least for this month. I viewed it like I normally do, 6mm eyepiece (magnification of 166x) it’s still quite bright in the sky. From what I’ve read it’s going to be dimming a bit by the end of the month as we (Earth) moves further away from it since opposition. I then tried a filter; I believe this is my first time using a filter to view anything other than the moon. The filter I used was a No. 12 Yellow filter. It seemed to work ok, but it dims Saturn and didn’t really bring out too much significant detail of the planet through my telescope, although it did make it did tone down the brightness enough to let me see a little more detail in the rings.

Anyway, that was my “quick” night of viewing. Hopefully I’ll have a couple more reports from this weekend. So much depends on the weather.