Nov 182016
 

Once again the diminutive FOV of my system does not lend itself to extended objects. Thus, it does not do the Heart Nebula justice. In fact this image only shows the central part of the heart shaped portion of IC 1805. However, it does show the small very young cluster of stars (Melotte 15) that ‘lights up’ the nebula. Several of the stars have estimated masses in excess of 50 times that of the Sun and it is those stars whose extreme output provides the energy to excite the surrounding hydrogen cloud into emitting the familiar red light. The energy is also what is sculpting the surrounding cloud into the fanciful shapes visible in the image.

The Heart Nebula (IC 1805 detail) [Ha:67x120s ]

The Heart Nebula (IC 1805 detail) [Ha:67x120s ]


This image is taken through a Hydrogen-Alpha filter that limits the light passing through to that with a frequency of 656.28 nm. In addition to distinctly showing where the energized hydrogen is located, it also is one way to limit the effect of a nearly full Moon and common light pollution. This image was taken on a full Moon night.
 
Chart generated with Cartes du Ciel

Chart generated with Cartes du Ciel

 Posted by at 14:48
Sep 172016
 
The constellation Cygnus (the Swan) has 5 bright stars that forms the shape of the bird in flight. The star at the intersection of the swan’s wings and body is named Sadr; the Arabic word for chest. The Bayer designation is Gamma Cygni (γ Cyg, γ Cygni).

The constellation is bright and easy to identify in the Northern sky. What is not so easy to see is the very large emission nebula located near γ Cyg.

Although γ Cyg lies near the center of the nebula, it is only a chance alignment. The star lies about 1,500 ly’s from Earth but the estimated distances to the nebula average about 3,000 ly’s.

By IAU and Sky & Telescope magazine (Roger Sinnott & Rick Fienberg) via Wikimedia Commons

By IAU and Sky & Telescope magazine (Roger Sinnott & Rick Fienberg)
via Wikimedia Commons

(IC 1318)[C:60x60s]

(IC 1318)[C:60x60s]

Since γ Cyg is so bright, I positioned it out of the FOV to prevent it overwhelming the image. Also, this image is only a small part of the nebula since my telescopic field of view is much too small to view the entire object. The dark area that crosses the image is not a lack of stars but is instead a very dense part of the nebula which blocks the background light from reaching us.

Chart generated with Cartes du Ciel

Chart generated with Cartes du Ciel

 Posted by at 12:52
Sep 112016
 

NGC 281 is an HII nebula in the constellation Cassiopeia. Named only ‘recently’, it has been given the common name of “Pacman Nebula” due to its remote resemblance (if rotated correctly) to the video game character. The nebula is about 80 light years in diameter at its estimated distance of 10,000 light years.

Pacman Nebula (NGC 281) [Ha:60x120s]

Pacman Nebula (NGC 281) [Ha:60x120s]


Also visible are several small dark areas known as Bok globules. These are areas of very dense dust and gas and can be the location of new star birth. Additionally, visible in the upper right quadrant are several sculpted columns slowly eroding from the intense output of IC 1590; the star cluster illuminating the nebula.
 
Chart generated with Cartes du Ciel

Chart generated with Cartes du Ciel

 Posted by at 18:41
Sep 012016
 

Quite often, astronomers adopt a common name for a celestial object based on what it ‘looks’ like to them. Just as often it takes a very vivid imagination to see what the astronomer saw. Most of the common names were based on photography using fairly primitive cameras, equipment and techniques. Modern imagery taken with today’s CCD cameras and processed with computer software, look nothing like the common names associated with the celestial objects.

This is not one of those times.

This nebula quite obviously has a bubble blown in it. The star right of the bubble’s center and slightly above and right of the bright knot of gas is the guilty party. This young star has about 20 times the mass of the Sun and its energy output is several hundred thousand times that of our star. This is what is blowing the bubble in to the surrounding molecular cloud. The cloud of gas and dust is more dense on the right side of the bubble and thus is constraining the expansion more on that side.

Bubble Nebula (NGC 7635)[Ha:76x35s]

Bubble Nebula (NGC 7635)[Ha:76x35s]


 The nebula is located in the constellation Cassiopeia and is about 7,100 LY from the solar system. It was discovered in 1787 by German born British astronomer William Herschel. The bubble is about 7 LY in diameter and is expanding at a rate of 25 km/s (54,000 mph). The temperature at the bubbles boundary is about 8180 K (14,264 °F).

Chart generated with Cartes du Ciel

Chart generated with Cartes du Ciel

 Posted by at 11:06
Aug 152016
 

NGC 6791 is an open star cluster in the constellation Lyra. Discovered in 1853, it is unusual in that there are three distinct populations of stars in the group. Along with a group of 8 billion year old normal stars there is a group of white dwarfs with a 6 billion year age and a group of white dwarfs with a 4 billion year age. This is contrary to the classic definition of open star clusters such that the stars of such a group are all born from the same molecular cloud and all have the same general age. Needless to say, this cluster has astronomers questioning their understanding of cluster formation and is heavily studied.
 
NGC 6791 was one of the few deep sky objects included in the field of view (FOV) of the Kepler spacecraft during its primary science mission.

(NGC 6791) [C: 56x60s]

(NGC 6791) [C: 56x60s]


Chart generated with Cartes du Ciel

Chart generated with Cartes du Ciel

 Posted by at 23:59