AAAA Observing Reports
An Introduction to
Spring
Deep Sky Objects
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The purpose of this program is to provide a starting point for new astronomers to begin their exploration of the sky. With the help of the star charts on the back, and the slide show this evening, you should be able to find each of the objects mentioned on this page. The constellations and objects were chosen from some of the major deep sky objects that can be observed during the spring season.
As you find each object, use an observing form to log your observations. We have
provided an official AAAA
Observing Log in PDF format for your convenience. To begin, find the
constellation with your naked eye, then look for the object with binoculars. Finally, use a telescope to view the
object up close. Enlist the help of your friends as necessary.
Orion
Orion is one of the most easily recognized of all constellations. Led by the bright stars Betelgeuse and Rigel, this constellation holds many fine telescopic and binocular objects, along with some of the most photographed regions of the sky. Its arrival in the night sky in December signals the beginning of the winter observing season, with its crisp, clear nights and fine “seeing”. It continues to share its wonders until early spring, when it finally disappears into the west in late April.
M42 - The Great Nebula in Orion—One of the finest sights in the entire sky, M42 is easily visible to the naked eye as the “fuzzy” star in the middle of Orion’s sword. It appears distinctly nebulous in binoculars or finder scopes, and shows an amazing amount of detail through the telescope. It is fully a degree in extent, with a wealth of fine curling wisps of nebulosity curving out from the brightest region surrounding the four relatively bright stars known as the Trapezium. On good nights with low power, I have even been able to see colors in this object. The region around the Trapezium appears as a cold steel blue color, while the wispy regions further away can appear as a soft ruddy pink.Slightly separated from the main nebulosity is M-43. This nebula is seen as a comma shaped cloud surrounding an eighth magnitude star just north of the Great Nebula. The more time you spend in this area, the more fine detail you can seen.
Ursa Major
Ursa Major is one of the most well known constellations in the heavens. It contains the famous grouping of stars known as the Big Dipper, which is often the first group of stars learned by people in the northern hemisphere. Several other "firsts" are associated with this constellation; the star Mizar was the first double star to be discovered through a telescope (1662), the first star to be photographed (1857), and the first star to be identified as a spectroscopic binary (1889). Also, the star Xi UMa was the first binary star to have its orbit calculated .
M-97—The Owl Nebula is of interest as the only large planetary nebula viewable in the spring skies. You will have to wait until early summer for the chance to view another. This large planetary nebula is almost 3' in diameter, and appears as a gray puff of light, slightly brighter in the center. At times, especially with averted vision, the "eyes" of the owl can be seen as two slightly darker spots.
Canes Venatici
M-51—The Whirlpool Galaxy. This is probably the finest example of a face on spiral galaxy in the northern hemisphere. It is about 10-15' in diameter, with a bright center and rather easily seen spiral arms. Just a few arc-minutes to the northeast is its companion galaxy, NGC 5195. This object is small, about 3x2', with a brighter center, and seemingly connected to M-51 by a bridge of stars.
Galaxies require special techniques such as averted vision and shaking the telescope tube, to coax detail out of them. Patience and practice will reward the persistent observer with details unseen by more casual observers.
M-3—This pretty globular cluster in Canes Venatici is almost easier to find starting in Bootes. While it is somewhat difficult to find, it is worth the trouble to do the search, since it is almost as spectacular as M13 in Hercules. M3, which is the only major globular cluster in the spring sky, is about 12-15' in diameter and handles magnification rather well. There are many stars arranged in curving chains resolved at its edges. The center is very dense, and was not resolved in my scope, which showed a granulated center.
Canis Major
M-41—Large and splashy, this fine open cluster in the constellation Canis Major is easily seen as a hazy patch to the naked eye, and is fully half a degree in diameter in the telescope. About 60-70 stars can be seen at low power, in many curving chains. The cluster is dominated by a bright orange star near its center. A great open cluster.
Also containing Sirius, the brightest star visible from earth, the constellation of Canis Major is one of the few constellations in the heavens which resembles what it is supposed to be: a large dog.
Cancer
Cancer is a small but important zodiacal constellation. It was the fourth constellation of the ancient zodiac, east of Aries, Taurus and Gemini, but is now fifth, since the first point of Aries, the point of the astrological Spring Equinox, has moved west into Pisces.
M-44—The Beehive Cluster. This bright open cluster (NGC 2632) is easily seen with the naked eye from a dark sky site. It is large, over a degree in diameter, and is best seen in binoculars or view finder. It is a somewhat loose cluster of about 50-100 stars, with several star chains and pairs seen.
M44, often dubbed the Beehive Cluster, is also commonly known as Praesepe, or Crib, because it is sometimes associated with the Manger of Christian teachings. It is one of the largest, nearest, and brightest of the galactic star clusters.
Praesepe, easily visible to the naked eye in a dark sky, was one of the few clusters mentioned in ancient times, although its true nature as a group of stars was not known until the invention of the telescope. According to legend, Praesepe was used in ancient times as a weather indicator. The invisibility of this cluster in an otherwise clear sky was considered to forecast the approach of a violent storm.
(Excerpts from Constellation of the Month articles by Rick Raasch.)
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