Orion: Stars of the night

Vince A. Sempronio likes to show 1his 4-year-old son, Luca, the stars. As an amateur astronomer, Mr. Sempronio, 50, looks at the night sky from his back yard in Bethesda.

Gazing at the sky is a way to put human existence into perspective, he says. Staring into the heavens has been his hobby for about 40 years. He is a member of the National Capital Astronomers, a nonprofit organization that is the astronomy affiliate of the Washington Academy of Sciences.

“I have used my telescope to give others the same views of the objects that I have come to enjoy,” Mr. Sempronio says. “A lot of people have just seen the stars in books or magazines and have never seen an object, or even the moon, through a telescope.”

Wintertime is a good season to enjoy the stars and their constellations. With advancements in technology, most professional astronomers use computers to study the sky. Amateur astronomers and some professionals, however, still gaze at the stars with a naked eye.

Orion, the hunter from Greek mythology, is the most prevalent constellation in the sky during the winter, says Harold Williams, planetarium and physics lab coordinator at Montgomery College at Tacoma Park.

Although Orion can be seen almost anytime of year, when it is referred to as a winter constellation, it means it can be seen rising in the east in the evening hours. During summer, Orion appears in the sky during the early morning.

If a person watches the sky tonight around 9, Orion will appear on its side about 30 degrees above the horizon between east and southeast. Orion’s belt will be vertical to the horizon. As midnight approaches, Orion becomes vertical as it goes into the southern part of the sky.

“It’s the best constellation to learn first,” Mr. Williams says. “People see dippers all over, but hardly anybody sees Orion, except for where it really is in the sky.”

The brightest star in Orion is Betelgeuse or “Beetle Juice.” In the traditional way of drawing the figure, Betelgeuse is located in Orion’s armpit, Mr. Williams says.

Another bright star in the constellation is Bellatrix, which is to the right of “Beetle Juice.” The three stars of Orion’s belt, Mintaka, Alnitak, and Alnilam, are powerful as well. Below the belt is Rigel, a blue white star, because of its high temperature.

“Many of the constellation figures don’t look like the figures people draw,” Mr. Williams says. “The connected points are very strained, but Orion does look like it. Six of the stars are very bright. Once you get used to looking for it, you can find it all the time, but until you get used to looking for it, it’s not as easy.”

Once a person has found Orion, it’s easy to find other constellations in the sky, Mr. Williams says. The stars in Orion’s belt point to Sirius, the brightest star in the night sky in the constellation Canis Major, one of Orion’s hunting dogs.

After finding Sirius, people sometimes look for the constellation Gemini, which is depicted as two twins. It is best known for its two bright stars Castor and Pollux, the names of the twins. Between Castor, Pollux and Sirius is the constellation Canis Minor, in which Procyon is the brightest star.

Further, this year, Saturn is between Castor, Pollux and Canis Minor. Last year, Saturn also was in Gemini, but next year it will be part of the constellation Cancer.

“Saturn takes 33 years to go around the sun,” Mr. Williams says. “It’s a wandering star. It moves, just like the Earth does, around the sun.”

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