Orion Zoom from Lookout Observatory
Dear Friends of Lookout Observatory,
Orion, The Hunter, is one of the most recognized and beautiful of the 88 officially-recognized constellations in the sky. This time of year it rises in the evening, having cleared the eastern horizon by 8 PM. By midnight it is near its highest, about half-way up in the sky to the south. Its brightest stars can be seen even from the light-polluted skies of major urban areas, but it becomes spectacular from rural, dark skies.
Image #1: This is a photo from rural Lookout Observatory, showing the tops of pine trees at the bottom and Orion just left of center. ( Ignore the yellow rectangle for now.) The main body of Orion consists of four bright stars forming an upright, somewhat crooked rectangle. The upper left star is reddish-yellow Betelguese, and the lower right one is bluish-white Rigel. In the middle are three bright stars at a 45-degree angle, representing Orion’s belt. These stars point down and to the left to the brightest star in the picture (and the brightest star in the night sky), Sirius. Just below Orion’s belt are 3 or 4 bright points in a vertical line, considered to be Orion’s sword. Because this photo is a 6½-minute time exposure, everything looks much brighter than what you can actually see with the naked eye. Now pay attention to the yellow rectangle. If you enlarged that section of sky about 5 times, you would be looking at the area in the next picture.
Image #2: This image is not actually an enlargement of the first photo, but rather a photo taken with a longer focal length (telephoto) lens. It is a 34-minute time exposure. Here the three bluish “belt” stars and the bright “sword” below are prominent. You can also see that the “sword” consists not only of stars but of some bright bluish and pinkish nebulosity. The brightest (pink) part is the famous Orion Nebula. I deliberately enhanced the red in the photo to bring out the great amount of nebulosity that engulfs much of the area of sky within Orion. This is the Orion Molecular Cloud Complex, huge clouds of dust and hydrogen gas caused to glow (“emission nebulae”) by the energy from embedded stars and star clusters. Every nebula I name in this report is part of this vast complex. This is a major area where new stars and planets are forming by gravitational condensation. These gaseous clouds are several hundreds of light years across, and centered about 1400 light years away. The large red arc to the left is part of this nebulosity known as Barnard’s Loop, named after the man who first discovered it using long-exposure photography. The yellow rectangle focuses on the lower left “belt” star – named Alnitak – and the nebulosity below it. If you enlarged it 5 times, you would be looking at the area in the next picture.
Image #3: This is a 95-minute exposure. Just to the left of the “belt” star (Alnitak) is the orange Flame Nebula, an emission nebula energized by the cluster of young bluish stars embedded (and completely hidden) it in, and by Alnitak. The red nebulosity below Alnitak, known as IC 434, is caused to glow by the energy from the bright star to its right, halfway toward the right edge. Silhouetted against this gas is the dark gas and dust cloud known as the Horsehead Nebula. If you magnify the area of the yellow rectangle about 5 times, you get the final picture,
Image #4: This is an 88-minute exposure. If you turn sideways (or download the image and rotate it counter-clockwise), you can see the Horsehead standing upright. To get a sense of how immense this formation is, imagine a series of orbits of the Earth around the Sun laid across the neck of this “horse” like a necklace. It would take more than 30,000 Earth orbits to cross the neck! It is a bit over one light-year across. The bluish nebula near the upper right corner, NGC 2023, about 4 light-years across, is mostly a reflection nebula, meaning the light we see is mostly reflected light from a hot blue star within the gaseous nebula. With this image you have zoomed in about 125 times compared to the first image. I hope you have enjoyed the trip.
Keep looking up,
Carter Mehl, (sometime) Resident Astronomer, Lookout Observatory
Click on any image to get a closer look
