Summer stars drive winter constellations over the horizon
The summer stars have driven the winter constellations over the sunset horizon, and even the “springy” form of Leo, the lion, has moved into the west.
Behind Leo comes brilliant Arcturus, the brightest star in the northern dome of sky around the Earth. It can be found by following the curve of the Big Dipper’s handle, which “arcs to Arcturus.” The star ornaments the kite-shaped constellation Bootes, the herdsman. Just east of Bootes hangs the lovely Corona Borealis, or Northern Crown.
Below Bootes, reddish Mars, the star Spica (in Virgo), and Saturn (in Libra) are strung west to east. Meanwhile, low in the southeast, Scorpius is coming into view. Its brightest star is gigantic Antares, whose name means “rival of Mars.” This summer we have a nice chance to compare these two objects, keeping in mind that Earth is now moving away from Mars, and so the Red Planet is gradually fading.
The Milky Way hugs the eastern horizon during the prime evening viewing hours. In or near it are the three bright stars of the Summer Triangle: Vega, Deneb and Altair. These stars will reach their highest points in the sky during August and September.
To the west-northwest, Jupiter is making a last stand. It begins the month setting three hours after the sun, but by July it drops into the sun’s afterglow.
In the morning sky, Venus still shines brightly, though it’s rather low in the east. The lovely planet will have an encounter with a waning moon on the 24th; look about an hour before sunrise. You may also be able to make out the Pleiades star cluster above and slightly left of Venus.
June’s full moon, known to Algonquin Indians as the strawberry moon, rises the evening of the 12th. It will be quite round, with peak fullness occurring at 11:11 p.m. It follows a low trajectory across the night sky because all full moons appear opposite the sun; thus, they must be low when the sun is high—as in June.
Summer arrives with the solstice at 5:51 a.m. on the 21st. At that moment the sun will be directly over the Tropic of Cancer, and the Earth’s sunward face will be lighted from the Arctic Circle on one side of the globe to the Antarctic Circle on the other side.
The University of Minnesota offers public viewings of the night sky at its Morris, Duluth, and Twin Cities campuses. For more information and viewing schedules in Duluth, visit the Marshall W. Alworth Planetarium at www.d.umn.edu/planet.