North Americana and Pelican Nebulae – Photo by Rick Bria
The North American and Pelican nebulae are part of a huge hydrogen gas cloud located 1700 light years away in the constellation Cygnus. They are so named because their shapes resemble the North American continent (upper left) and the head of a Pelican (toward the bottom right).
This is just one of many nebulae in our Milky Way Galaxy. Stars form in large numbers from the gravitational collapse of these clouds. As stars form within the cloud their energy causes some parts of the nebula to illuminate, while other parts remain dark and are seen in silhouette.
Two local observatories collaborated to produce this picture of the North American and Pelican Nebulae. The Round Hill Observatory provided 8.5 hours of luminance data. This was combined in Photoshop with 1 hour of RGB color data from the Mary Aloysia Hardey Observatory.
The luminance data (from 2009) is a stack of 15 minute sub exposures through a narrow band hydrogen alpha filter taken with a FSQ106 refractor. The color data (from 2013) was from a Canon 60Da DSLR through a TeleVue 76 refractor. Luminance and color data were combined using a method called Luminance Layering. In this case the layering process was done twice. This is my first experiment with Luminance Layering. I think it is a very useful and potent method for combining two different data sets. I will apply this method to both archived data and planned targets going forward.
This picture of the Seven Sisters star cluster is a 24 minute exposure with a Canon T2i(a) Camera attached to a 76mm TeleVue telescope. Images acquired with BackyardEOS software.
Some M45 facts…
This star cluster is also known as the Pleiades, and is almost straight up in the winter sky. The Pleiades are located within the constellation Taurus.
Like all star clusters, the Seven Sisters formed from the collapse of a huge gas cloud. It is estimated to have formed about one hundred million years ago.
Most people can see six or seven stars in this cluster without optical aid, but keen eyed observers in very dark skies have seen as many as fourteen. Careful studies with modern equipment have found almost five hundred stars in an area fifteen light years across.
Often mistaken for the little dipper, the Seven Sisters is the second nearest star cluster to us at 400 light years away. Notice the blue wispy nebulae in the picture. It was thought this nebula was left over gas from the cluster formation and had yet to be absorbed into the cluster stars. It is now known to be foreground gases in the same line of sight.
I find it very interesting that our own Sun could have formed in a star cluster much like the Seven Sisters and drifted out on its own in the in the five billion years since. Star clusters drift apart after a two or three hundred million years so we may never know the ‘birthplace’ of our Sun.
The crater Clavius and the Lunar Highlands – photo by Rick Bria
This picture was taken at the Mary Aloysia Hardey Observatory September 4, 2014. It is a stack of 1800 video frames Taken with a Canon 60Da DSLR. The data was processed in several pieces of software including AutoStakkert2 and RegiStax6 to achieve this result.
The picture is centered on the crater Clavius located in the ‘Lunar Highlands’. The lunar highlands are littered with impact craters and have almost no smooth low areas. The cratered highlands are older than the smooth basins known as Maria. The highland craters formed about 4 billion years ago when our Moon, the Earth and all the other planets were pummeled by comets and asteroids. This theorized violent impact period is called the ‘Late Heavy Bombardment’.
Measuring 136 miles in diameter, Clavius is one of the largest impact craters on the Moon. An interesting feature that I always look for while observing Clavius in the telescope is the arc of five craters located inside Clavius. The craters in the arc start out small and get ever larger. See if you can find them in the picture. Good hunting.