Starwatch

I don’t know about you, but by this time of February I get really itchy for springtime. Winter’s dragged on long enough. But there are signs of spring in Washington – the daylight hours increasing, the birds singing a little more, and your income taxes due in less than two months.

Early in the morning before morning twilight there’s even summer in half of your environment, the celestial dome. Between 5 and 6 a.m., the early morning sky of stars and constellations is the same one we’ll see in the evening after twilight on the Fourth of July. Sure it’s not as warm as it’ll be in July, but at least the mosquitoes are still in their winter slumber.

Which constellations we see around here and their placement in the sky is simply determined by what direction Everett is facing toward outer space. That’s determined by Earth’s 24-hour rotation on its axis and its 365-day orbit around our home star, the sun. It just so happens that in the wee hours of the morning we’re pointed the same direction in space as we are in early July in the evening. In fact any early morning you check out the celestial dome you’ll get a preview of what you evening sky will look like in another five months.

If it’s dark enough where you are you’ll see the bright band of the Milky Way stretch from north to south across the eastern half of the sky. The band is the combined light of millions of stars in the thickest part of our galaxy. In some Scandinavian cultures it’s referred to as the road to heaven. The Milky Way band is out on winter evenings, but it’s not nearly as bright as it is in the summer sky. During the summer months the nighttime side of Earth is facing the center of our galaxy.

Two of my favorite summer constellations, Scorpius and Sagittarius, are in the low southern sky these early mornings, and both of these constellations are also in the direction of the center of the Milky Way, about 30,000 light years away. If it weren’t for thick clouds of gas and dust obscuring our view of the Milky Way, that part of the sky would be perpetually as bright as a full moon.

Scorpius is one of the few constellations that looks like what it’s supposed to be, a giant celestial scorpion. There’s a bright dark reddish star, Antares, marking the scorpion’s heart, and the curved tail of the beast drags along the southern horizon. Sagittarius, to the left of Scorpius in the low southern sky, is supposed to be a half-man, half-horse shooting an arrow – according to Greek and Roman mythology. If you have a very active imagination you’ll see the centaur archer, but most people see is for what it really looks like, a giant teapot.

These two summer constellations are bookended by two bright planets. To the upper right of Scorpius’s head is Jupiter. You can’t miss the largest planet in our solar system. To the upper left of the Sagittarius teapot handle is even a brighter object – the planet Venus. It’s the brightest starlike object in the sky right now because it’s just 40 million miles away, but that’s not the only reason it’s as bright as it is. Cloud-covered Venus is extremely reflective. Like all planets, Venus emanates no light of its own but reflects sunlight, and it does so very efficiently. What’s really amazing is that we’re not even seeing that much of Venus. It’s lying nearly in a line between Earth and the sun, so we only see a thin slice of the planet. Even through binoculars you can resolve the crescent shape of Venus, and if you’ve really been eating your carrots you might even see the crescent with your naked eye.

As an added attraction this week you’ll see the waning crescent moon migrating to the east from morning to morning among the stars and planets around Scorpius and Sagittarius. On Thursday morning you’ll see a nice celestial “kiss” between Venus and the moon with the crescent of the moon just 10 degrees to the lower right of crescent Venus.

Enjoy summer evenings in February.

Mike Lynch is an amateur astronomer and professional broadcast meteorologist for WCCO-AM radio in Minneapolis and author of the new book “Washington Starwatch,” available at bookstores and on his Web site, www.lynchandthestars.com.