From August 10th I captured 30 good frames at 240 seconds each to get this image of M92. With an apparent magnitude of 6.3 it is one of the brightest globular clusters visible from the Northern Hemisphere at a distance of 26,700 light years away.

“Messier 92 is a globular cluster of stars in the northern constellation of Hercules. It was discovered by Johann Elert Bode in 1777”

“Characteristic of other globulars, Messier 92 has a very low abundance of elements other than hydrogen and helium; what astronomers term its metallicity. Relative to the Sun, the abundance of iron in the cluster is given by [Fe/H] = –2.32 dex, which equates to only 0.5% of the solar abundance. This puts the estimated age range for the cluster at 11 ± 1.5 billion years.”

M92 Full Scale

Next is a crop of the lower right edge where several galaxies but in.

M92 Crop

 

Another year and my gaze turns to the lovely Pleiades cluster. This is hard for me to image because of the very bright stars and the diffraction spikes and the associated “star” artifacts. I lowered my sub exposure time to 120 seconds but next time I should go even lower. More subs is a good thing especially when dithering like I am. There is 1 hour 50 minutes here, or 55 exposures combined here.

 From last Monday night I had a good clear sky where I was able to get out for a few hours. I was capturing 400 second exposures for a total of 1 hour 40 minutes of integrated time. Using dithering between shots and just flat frames and bias frames for stack calibration, I spent some time in Photoshop to get this final image. Nothing  too spectacular, but I like these kind of targets with my setup while I am trying to use longer exposures. Seems all the clear skies have a big fat moon in the sky lately…. Guess I will have to just look at the moon!

 

NGC1893

Up at a decent height in the northeast sky by 1:00 AM last night one of my favorite subjects, FIREWORKS!  Well the galaxy at least! 9 subs of 360 seconds each at ISO 1600 for this dim object brings out a crowded field of stars along with the much closer open cluster know as NGC 6939

From Wikipedia:

(Fireworks Galaxy) “Discovered by William Herschel on 9 September 1798, this well-studied galaxy has a diameter of approximately 40,000 light-years, about one-third of the Milky Way’s size, and it contains roughly half the number of stars as the Milky Way. The galaxy is heavily obscured by intersteller matter as it lies quite close to the galactic plane of the Milky Way.” 

“NGC 6939 is located near the border of the constellations Cepheus and Cygnus, at the southwest corner of Cepheus. The open cluster is located  2/3° northwest from the spiral galaxy NGC 6946 (The Fireworks Galaxy), which has visual magnitude 8.8. They appear as two patches of haze with 10×50 binoculars. NGC 6939 can be glimsed with 7×35 binocoluars where as 25×200 binocoluras are required to start resolve the cluster. The cluster can be glimsed with a 4 inch telescope and is resolved at x72 magnification.”
Fireworks Galaxy with neighboring open cluster