The constellation Orion, in my view, is a symbol of winter. Orion is seen rising in
the East in fall, is high in the south during winter, and sets in the west in
spring. Orion is fairly easy to find in the sky, this time of year it is found in the southwest after dark. It contains many bright stars and is the only constellation to have three bright stars in a row. It is also used as a signpost to find other constellations.
The three stars in a row form Orion’s belt, and if the line from the belt stars is
extended down it can be used to find Sirius, the brightest star on our northern
sky (not pictured). If the belt stars are followed up, they will lead you to the star Aldebaran in the constellation . The belt stars are sometimes called ‘The Three Marys’ or ‘The Three kings’.
The star Betelgeuse (labeled B) is one of the largest stars known. It is 640 light years distant, but if it were placed where our sun is now, this red giant star would
swallow all the planets, including Earth, out to Jupiter.
Rigel, a blue-white giant star (labeled R) is 800 light years away. Notice the
difference in color between Rigel and Betelgeuse. Star color comes from
temperature, blue being the hottest. The color difference of these two stars
can be seen with just your eyes if you look carefully. Try it some night.
The Orion Nebula (cataloged as M42) is a huge gas cloud below the belt, in the sword of Orion. It is labeled 42 in the constellation picture. Gas clouds like M42 are where stars form. The gas cloud collapses from gravity until the forming stars
are hot and massive enough to begin the process of fusing hydrogen into helium. The Orion Nebula is 1400 light years away and 50 light years in diameter. Many ‘new’ stars have already formed in the core of the Orion nebula, and it is thought that many thousands of stars will form in the future. Being one of the brightest nebulae in our sky, it is a sight to behold in a telescope.
The entire Orion constellation is sprinkled with nebulae of all shapes and sizes. If one looks carefully in the constellation picture many reddish patches appear. Nebulae often appear reddish as this is the color of hydrogen gas when radiated by nearby stars. The Rosette nebula is just one example and is labeled in the
lower left of the picture. Starry Nights!
Orion Nebula image technical details:
Exposure: 72 minutes through a 76mm TeleVue telescope w/.8FF
Camera: Modified Canon T2i(a) with BackyardEOS
software for image acquisition.
Image assembled in MaximDL - Processed in Photoshop CS5
Mary Aloysia Hardey Observatory at the Convent of the Sacred Heart. 2012-01-15
Orion Constellation image technical details:
Canon T1i Camera with 28mm lens @ f/4
2 stack - 240 second exposure @ ISO-800 (8 minute exposure equivalent)
Image assembled in MaximDL – Processed in
Photoshop – 2010-11-13 Bunker Hill - Lakeville, CT