The North American Nebula and Pelican Nebula

Click on picture for large view

Now directly overhead in my part of the world (Kansas City area), the North American Nebula and the Pelican Nebula are very rich areas of gas and dust in the Milky Way. The very dark area, right in the middle of the picture, is actually thick dust and gas in front of the nebulae, but it easily marks the similarity to Florida and the Gulf of Mexico. The nebula that looks like a pelican holding a fish in its beak is to the right of the North American Nebula. The bright star at upper right is Deneb, the brightest star in the constellation Cygnus, the swan. This is a very large area of sky. Four full moons would fit in the North American Nebula. From a dark sky site, away from the light pollution of the city, you can see it without optical aid, looking like a brighter region of the Milky Way. Binoculars improve the view, but a telescope has too much magnification not allowing you to make out the over all shape. It is best seen in wide view photographs.

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Techinical Photo Info:

Camera: Q453 CCD

Lens: Canon 70-200mm f/2.8 L IS

Focal Length setting: 200mm

Aperture setting: f/4

Exposure: 7 X 10 minutes totaling 70 minutes

Darks: 2 darks to create a dark pixel map

Flats: 20

Biases: 0

Mount: Celestron CGE

Guide Camera: Q-Guider by CCD-Labs

Aligned and Stacked in Nebulosity with final processing in Photoshop

Gone To The Dark Side

Click on the Images for a large view

Most of the time, astrophotographers try to image dim objects, trying to make them brighter so that they are easier to see. However, there is one type of object in the night sky that emits no light. Because they emit no light, they appear as dark regions among the starry sky. At the upper right of the top picture is the famous Plieades Star Cluster, with its glowing reflection nebulae. The rest of the picture has many areas with very few stars. These are the so called "Dark Nebulae". At one time astronomers thought these were holes in the sky, letting us see space beyond the stars. We now know that instead of holes, what we are seeing is dark clouds of dust and gas so dense that they block the light of the stars behind them. If you can't see the dark nebulae, you need to adjust your monitors brightness setting.

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The first person to prove this fact was Edward Emerson Barnard in the early part of the last century. E.E. Barnard was a self taught astronomer, who was the first person to use the newly invented camera on the night sky. He obtained thousands of photographic images of the Milky Way, then selected the 50 best for publication in his "Atlas of Selected Regions of the Milky Way". He approved each photograph for each and every book, therefore there were only about 700 books published. Each picture in the book is an actual photograph, not a printing press facsimile. So this is a rare and much sought after book.

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Along with the photographs, in a seperate volume, there are charts with all the dark nebulae numbered by Barnard. There are 370, with each number starting with the letter B. In the above image, I have captured 15 of these nebulae. Click on the bottom chart to see each numbered object.

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If you would like to see images from the Atlas, they are on the internet. The Georgia Institute of Technology Library and Informatin Center scanned the book and placed them here: http://www.library.gatech.edu/barnard/

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Technical Photo Info

Camera: Canon XTi

Lens: Canon 70-200mm f/2.8 L IS

Focal Length setting: 70mm

Apeture setting: f/4

Exposure: 11 X 8 minutes totaling 88 minutes

Darks: 20

Flats: 20

Biases: 20

Mount: Celestron CGE

Guide Camera: Q-Guider by CCD-Labs

Aligned and Stacked in DeepSkyStacker with final processing in Photoshop

What is it? An apple core, dumbbell, football or a planet?

Click on image for a larger view

345 years ago, while looking for comets, Charles Messier discovered this nebula in the sky and numbered it the 27th object in his list of objects that were not comets. He called it an "oval nebula". Sixty four years later, in 1828, another astronomer, John Herschel, wrote that it was shaped like a dumbbell, and it has been called that ever since. Looking through a telescope, I always have the impression that it looks like an apple core. With long exposure photography, dimmer areas become visible turning it into a football. These type of deep sky objects are also known as planetaries. Definitely not planets, in the 18th century astronomers coined them planetaries because they looked very similar to the gas giant planets, mostly round and diffuse. Unfortunately, that name has also stuck.

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A planetary nebula is something that humanity will see up close and personal some time in the distant future. At that point in time, about 5 billion years, it will destroy the Earth and everything on it. What you see in the Dumbbell Nebula is the death throes of a star similar to our Sun. This dying star, which you can see at the center of the nebula, had previously grown into a Red Giant, and is now pulsating and shedding off it's outer layers into space. The extremely hot central star radiates ultraviolet light into these outer layers making it glow.

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Technical Photo Info

Camera: Q453 CCD by CCD-Labs

Telescope: 10" f/5.5 Newtonian with a Coma Corrector in the optical path

Mount: Celestron CGE

Guidescope: 60mm Dia., 400mm Focal Length

Guide Camera: Q-Guider by CCD-Labs

Exposure Length: 7 X 10 min exposures for a total of 70 minutes

Darks: 1 Dark to create a Dark Pixel Map to get rid of hot pixels

Flats: None

Biases: None

Aligned and Stacked in Nebulosity with final processing in Photoshop