Stars over Sisters

The month of August 2012 is highlighted by two special astronomical events. The first is the Perseid meteor shower. You can see meteors from July 23 through August 22, however the peak of the shower is August 11-13. At the peak, the shower can produce up to 60 meteors per hour, so if you spend just 10 minutes looking, you're bound to see a meteor or two. The streaks of light will appear to emanate from the northeastern sky, near the constellation of Perseus. These meteors are caused by material, left behind from comet Swift-Tuttle, that enters the earth's atmosphere and is incinerated by the heat of friction.

The second event will be a blue moon (but don't look for a drastic color change). This means that a full moon occurs twice in one month, which only happens every two or three years on average. The moon will be full on August 1 and again on August 31 (the blue one). The remainder of the lunar cycle is as follows: last quarter on August 9 when only the left half of the moon is lit; new (dark) on August 9; first quarter on August 17 when the right side of the moon is illuminated.

The planets Mars and Saturn still rule the evening sky and will be visible near each other in the constellation Virgo, which is low in the western sky. Meanwhile, Venus, Jupiter, Mercury and Uranus can be seen in the east just before dawn (August 6-31).

On August 24 Neptune will be at opposition as it transitions from a morning planet to an evening object. At that time it will be at its closest point to Earth and well placed for observation. However, unless you have a very powerful telescope, it will only appear as a small blue dot.

Look for the constellation Cygnus, the swan, this month. The constellation is also known as the Northern Cross, since the brighter stars in the constellation also resembles a cross. Cygnus can be found high in the eastern sky at nightfall. Deneb, the brightest star of the constellation, denotes the tail of the swan, or the top of the cross. Deneb is also a member of the Summer Triangle, along with Vega (in Lyra) and Altair (in Aquila).

One myth regarding Cygnus relates that he was close friends with Phaethon, who was killed by a fire bolt shot by Jupiter. Overcome with grief, Cygnus began to weep. As he did so, he transformed into a beautiful bird that lived in lakes, and he stayed away from the flames that killed his friend.

One of the finest examples of a diffuse nebula is found in Cygnus. Known as the North American Nebula because its shape somewhat resembles the continent of North America, this collection of interstellar gas and dust is the birthplace of many new stars. This object is estimated to be about 100 light-years across and is located only 1,600 light-years from Earth, a relatively short distance.

If you are interested in learning more about astronomy, consider attending the next Stars over Sisters star watch on the evening of August 17. The event begins with a presentation at 8:30 p.m. at the Sisters Park & Recreation District (SPRD) building. Telescopes will be set up on the Sisters High School soccer field for viewing the night sky after the talk. All are invited and there is no charge. Then on August 21 the Sisters Astronomy Club will hold its monthly meeting, also to be held at SPRD beginning at 7 p.m. All are welcome to attend.