Looking Up column: Enjoying Orion, the Hunter
The banner constellation of Northern Hemisphere winter evenings is certainly Orion. The pattern, dominated by bright stars and three in a neat row right in the middle, is unmistakable.
Orion and the Big Dipper are easily the most well-known star patterns north of the equator (the Big Dipper being the brightest portion of a larger constellation, Ursa Major the Big Bear).
Around 10 p.m. on mid-January evenings, Orion is highest in the south. The Big Dipper is directly opposite in the north, and at this hour and time of year, appears to be balancing on its “handle” with “bowl” stars on top.
Orion has been celebrated and admired certainly since anyone paid attention to the night sky, millennia ago.
The ancient Greeks referred to Orion as “the Hunter.”
I like looking back (as well as “looking up”) into history.
Garrett P. Service described Orion in his 1908 book, “Astronomy with the Naked Eye.” He described the balance and color contrast between the figure’s two first magnitude stars, gleaming white Rigel at lower right, and fiery red-orange Betelgeuse at upper left, with the stunning triad, the “Belt of Orion” tipped at an angle, right between. Betelgeuse and Orion are each about 10 degrees from the center Belt stars.
“Their splendid contrast of color, and the dazzling beauty of the stars in the Belt, which lie in an almost true straight line, and are matched perfectly in size and tint as selected gems, impart to this constellation the appearance of a gigantic piece of jewelry,” Serviss wrote. “There is nothing else in all the sky to equal its splendor.”
Orion is at least partly visible to everyone on Earth. The celestial equator passes right through the Belt. As viewed from the Earth’s equatorial region, Orion passes straight overhead. Someone on the north pole would only see the top (northern) half of Orion, as the celestial equator follows the horizon among the icebergs; the North Star is nearly overhead and the night is continually ablaze with northern lights.
From the south pole, the southern half of Orion appears above the frozen horizon.
Betelgeuse, a red giant star, fluctuates in brightness on an irregular schedule. You may recall this past winter, when night sky watchers and astronomers, in general, were amazed to see Betelgeuse make an unusual dip in brightness, rivaling the Belt stars and the other two corner stars in Orion, which shine at around +2 magnitude. Betelgeuse stayed that way for months; it was a relief to see it has regained its glory. The suspected cause of the dimming was a cloud of dust that was expelled from Betelgeuse, temporarily masking some of its light.
Take note of the string of stars making a line on the left side, below the three Belt stars. This is “Orion’s Sword.”
You should be able to see on close inspection that the middle star in the Sword is distinctly fuzzy. Binoculars will bring this out clearly. You are looking at the “Great Nebula of Orion,” designated as M42.
Astronomers point out that this is a scene where new stars are being developed from cosmic dust and gas. In a sense, we can call it a “stellar nursery.” There are many examples of these nebulae across the sky; M42 is the brightest.
A telescope, of say 6 to 10 inches aperture, will bring out incredible detail on a dark, clear night. Even a small telescope with a 3-inch mirror or lens will show the famed “Trapezium,” a cluster of four dim stars packed closely together like a little (imperfect) square, imbedded in the Great Nebula.
While there is practically no end to what you can explore with a telescope, this column stresses that none is really needed to appreciate the stars and other wonders of the universe that open to us every clear night. Orion was enjoyed for thousands of years before Galileo first turned a telescope that way in the early 1600s.
Betelgeuse and Rigel mark opposite corners of a tall rectangle. The corner star to the right of Betelgeuse is named Bellatrix. These can be imagined as Orion’s shoulders.
The corner star to the left of Rigel is Saiph; these two mark Orion’s feet.
The Belt stars, from the top right down, are named Mintaka, Alnilam and Alnita.
Making a triangle with Betelgeuse and Bellatrix, in the middle and above a line connecting them, is a dim grouping of three stars, the brightest being named Meissa. This is pictured as the “head.”
A long line of fairly faint stars to the right of Bellatrix neatly marks the Hunter’s catch, a lion’s hide, held up like a shield.
To the upper left of Betelgeuse is a group of dim stars outlining the Hunter’s “club.”
Looking Up frequently makes use of stars chart made available online through Pachamamatrust.org. These charts bring back special personal memories, as they appeared in a small pocket-size book, “Stars”, part of the classic Golden Nature Guide first published in 1951. “Stars” was written by Herbert S. Zim, Ph.D. and Robert H. Baker, Ph.D., D.Sc, and illustrated by James Gordon Irving.
This was one of the books that helped inspire me to appreciate the night sky as a preteen back when Apollo astronauts were preparing to go to the moon.
Orion has always captured our imagination and attention of the beauty of Creation of which we are a part.
First-quarter moon is on Jan. 20.
Keep looking up at the sky!
Peter Becker is managing editor at The News Eagle in Hawley, Pennsylvania. Notes are welcome at email@example.com. Please mention in what newspaper or website you read this column.