A whole new set of constellations
Wednesday, June 26, 2013
Well, here it is. Summer has begun and we are almost halfway through our year. Have you noticed how the sky has changed from our observations in January?
Well, for one thing we have a whole new set of constellations to look at, and for another the weather is sure a lot warmer.
However, the nights are much shorter. On average at the beginning of summer there are only five hours of dark astronomers can use for observation. Whereas in January we had 13 hours of astronomical dark useful for observing.
In January we had Orion, Taurus, Gemini, and Leo for our entertainment. Now, here in June, they have all left. All except for Leo and a piece of Gemini, but they are not long for the sky.
Looking east about an hour after local sunset we can find our old friend, the Summer Triangle about halfway up the sky. Vega is the brightest of the triangle's three stars standing in the top corner. Down and to the left is Deneb as the tail star of Cygnus, the Swan, and to the lower right of Vega is Altair in Lyra, the Harp.
The Summer Triangle is not a constellation, it is an asterism. An asterism is a grouping of stars put together into a pattern. Other asterisms include the Big and Little Dipper, the Winter Triangle, and the Winter Hexagon.
For our early evening entertainment, look west just above the horizon within a half-hour to 45-minutes after local sunset for the bright planet Venus.
Up until recently Venus and sister planet Mercury had been playing tag. But now Mercury is headed for the horizon soon to leave the sky while Venus will continue its upwards journey toward a July 3, meeting with M44, the Beehive star cluster.
Also for our viewing pleasure Scorpius has risen its three-star head in the south with it's fishhook-shaped body extending down to the horizon and then to the left. The bright star at the heart of the beast is bright red Antares, the so-called "Rival of Mars."
SKY WATCH: Sunday, June 30, first quarter moon. Tonight, June 26, the planet Venus and the stars Castor and Pollux in Gemini will line up in a straight line. The two bright stars will be to the right of the planet. Since you are out looking at Venus, use your binoculars placing Venus at about the 10 o'clock position on the left side of your field of view. Located at about the 4 o'clock position on the other side will be the asteroid Vesta (officially known as 4 Vesta, being the fourth asteroid discovered).
If you feel up to more planet-chasing, the ringed-planet Saturn is high in the south about an hour after local sunset, it is to the right of the star Spica. On Thursday, June 27, at 3 a.m., the moon will be near the distant planet Neptune.
Place the moon just outside the field of binocular view on the upper right side, the planet will be just outside the lower left field of view. Move it just a bit and you should find the tiny dot that is the planet. On June 30, the moon will be helpful in locating another of the outer gas-giant planets, Uranus. Only this time they will both be in the same field of view--barely. Best time to look is again at about 3 a.m.
NEXT WEEK: More astronomical blather.