Sunday, 24 April 2022 12:33

One classification of open clusters is the Trumpler classification. It consists of 3 parameters, the first is the degree of concentration.

I - Detached clusters with strong central concentration.
II - Detached clusters with little central concentration.
III - Detached cluster with no noticeable concentration.
IV - Clusters not well detached, but has a strong field concentration.

The second parameter is the range of brightness.

1 - Most of the cluster stars are nearly the same apparent brightness.
2 - A medium range of brightness between the stars in the cluster.
3 - Cluster is composed of bright and faint stars.

The last parameter categorizes the number of stars in the cluster.

p - Poor clusters with less than 50 stars.
m - Medium rich cluster with 50-100 stars.
r - Rich clusters with over 100 stars.

If the cluster any type of nebulosity, the letter "n" is added to the last parameter.


First up is Messier 34, located in the constellation of Perseus. Consisting of over 100 stars, in a space of a diameter of 14 light years. It is some 1,500 light years distance and shines at an apparent magnitude of 5.5 at an estimated age of 200 million years.

Friday, 24 December 2021 13:10

Messier 41 is an open cluster located in Canis Major near Sirius. The cluster contains some 100 members in a diameter of 25 light years. Estimated age of the cluster is around 200 million years. It is expected to remain as a cluster for 500 million years before dispersing. Brightest of the stars is an orange giant near the cent of the cluster. K3 type star, it has a magnitude of 6.3 and is 700 times more luminous than our Sun.

Wednesday, 22 December 2021 15:37

Messier 45, one of the more famous open clusters. Often called the Pleiades or the Seven Sisters, with the name Pleiades coming from Greek mythology. The cluster has been known since ancient times, and can be seen as a grouping of 6-7 stars, so it was interesting that Charles Messier included it in his catalog of objects that are not a comet, but could be mistaken for one.

The cluster is surrounded by a reflection nebula that the group is currently passing through, and not related to its original birth in a compact nebula. The cluster consist of at least 1,000 stars located in a radius of 8 light years. The cluster is dominated by hot blue luminous stars, but also contains many brown dwarfs that are not massive enough to initiate nuclear fusion. The estimated age of the cluster is around 100 million years, and its expected to take 250 million years to disperse due to gravitational interactions.

Also a bright knot was discovered around Merope by astronomer Edward Barnard that is being eaten away by the intense radiation from Merope. Due to the dazzling light from Merope, it is difficult to see, and later given the designation of IC 349, or is sometimes referred to as Barnard's Merope Nebula or Merope's Companion.


Friday, 10 December 2021 17:06

NGC 457 is an open cluster located in Cassiopeia, often called the Owl cluster, or a more recently the E.T. cluster with the two brightest stars forming eyes. I tend to see it more as an Owl. The cluster contains some 150 members and has an estimated age of around 21 million years. Less than idea weather for imaging, with a thin cirrus clouds, but a good bright target for commissioning the RC 10 scope and the ZWO 2600 mono camera.

Wednesday, 08 December 2021 18:11

NGC 157 is a spiral galaxy with somewhat distorted arms located in the constellation of Cetus. Discovered by William Herschel in 1783. Many other distant galaxies are visible in this area notated by PGC numbers.

Wednesday, 07 February 2018 17:16 is an web based network of remotely controlled telescopes currently based in four areas. The service has telescopes based in New Mexico, and California in the United States, in Spain, and in Australia. Using a web browser, one can control or upload a planned observation that can reserve telescope time and execute automatically at the appointed time. It describes itself as a Self-Funding Observatory with most of the profits invested back into upgrading their operation.

Friday, 01 July 2016 22:01

Here are a few of the images I've taken with the new camera and equipment. Still working out the bugs with the new equipment and camera.

First up is the Great Globular Cluster in the constellation of Hercules. Imaged under a full Moon, so not the best imaging conditions.

Friday, 03 June 2016 21:49

Just received a new camera, and no charge for the extended cloudiness that comes with any astronomical purchase. Received a just out ASI 1600MM-Cool camera. It is a 16 megapixel 4/3 CMOS sensor, that has a resolution of 4656 x 3520 pixels, and a pixel size of 3.8 nanometers. It also has a two stage TEC cooling system that can take the sensor down to 40C below the ambient temperature. It also has a very low read noise, which is good for deep sky, and with its relatively high frame rate it can also be used as a planetary camera. Looking forward to trying it out in both types of imaging.



Saturday, 23 April 2016 15:35

 After using the dome for several years, started thinking about the next observatory. Wanted the capability of using two scopes in those seeming rare clear moonless nights, and the ability to image without having to rotate the dome. At the time, automating my dome was looking rather difficult and expensive.

Settled on a roll off roof observatory, and after doing research, ordered plans for a SkyShed RoR. Picked the 10 foot by 10 foot one, based on my ability to haul the supplies, and most likely I would be building it by myself.

Thursday, 21 April 2016 14:44

 When you first start astrophotography, it quickly becomes apparent how much a convenience a permanent setup brings. First you have to bring out the tripod, the counterweights, and the scope. Then haul out the power, either battery(s) or A/C cord. Then a table for the computer, then the computer. Then all the cables to control the mount, the cameras. Then the mount has to be polar aligned with the axis of the earth so the mount can track objects better as they rotate through the sky. Of course, by then, clouds will appear out of no wheres.

So a high priority was to build a permanent setup for the scope and equipment. I decided to tackle building a dome, well because I think domes are cool. They also do a great job of blocking wind, reducing dew, and any stray light, which luckily I don't have much of a problem with.