August's night skies are so jammed with spectacles that it's hard not to get too celebratory about the whole thing.
This month, we have a special planetary conjunction, planets dancing with the stars and the moon, a meteor shower and loads of nebulae and star clusters. With the weather being as benign as one could hope for, at least as far up as the high foothills, there is really no credible excuse for not getting out there for a spell to enjoy the month's overfull of opportunity.
Picking a number one highlight is practically impossible, but the gradual Venus/Jupiter approach culminating with an extremely close conjunction in the east at dawn Aug. 18 is a serious contender.
Venus, blazing at magnitude minus-3.8 and Jupiter, at minus-1.8, will get to within 0.3 degrees of one another around 5 a.m., standing thereafter nearly 5 degrees above the horizon for about 45 minutes before sunrise. These two brightest stars in the solar system haven't been this close since May 2000. Note that because of the disparity of distances that the two planets have from the sun, Jupiter is only two percent as bright as Venus.
A conjunction happens when planets appear to line up within 5 degrees of each other. This August, two other planets line up, but not in what you'd call a conjunction.
On the nights of Aug. 1-4, Mars and Saturn, the moon and Spica, the brightest binary star in Constellation Virgo, "the furrow," all line up from north to south across the southwestern sky about one hour after sunset. Watch the moon traverse the troupe from the north each night, hopping between the other three to arrive between Saturn and Mars on Aug. 3. Look again as Mars pushes up within 3 ½ degrees of Saturn from Aug. 23-26. Finally, from Aug. 29-Sept. 2, watch Saturn, Mars and the moon tightly cluster on the 31st.
Saturn, in Constellation Libra, "the scales of justice," though low in the unstable atmosphere, still provides good telescope views of its open tilted rings. Mars, falling further back in the rear view mirror, is a cold, coppery-gold, featureless orb.
The annual Perseid meteor shower, radiating from Constellation Perseus, "the hero," usually gets its share of media hype, which frankly has proved unwarranted for this and most other meteor showers over the past many news cycles. This year is no exception: the moon will be two days past full when the great Perseids peak late Aug. 12-early Aug. 13. This strongly suggests a probable washout.
However, hardcore skywatchers who would not be so easily deterred should consider breaking with tradition and get out earlier than the peak to watch for the infrequent yet long-lived meteors called "earth grazers." The moon will be low in the east, as will Perseus's radiant, but the sky won't be awash with the dazzling waning gibbous moonlight yet. It's worth a shot, and you won't have to set the alarm for 2 a.m. for an exercise in futility.
Some of the most impressive features of the summer sky reside in constellations Scorpius' and Sagittarius' border region due south around 8 p.m. This part of the Milky Way is the center of the galaxy and hosts the galactic equator, not to mention an invisible black hole. Three barred arms of the galaxy intersect here, so skywatchers will find a seemingly endless array of open clusters such as the Butterfly Cluster (M6) and the Northern Jewel Box (NGC 6231), globular clusters of highly concentrated stars such as M80, as well as countless strings, trails, loops and speckles of stars.
Be sure to track down the numerous nebulae, both light and dark. One of the most famous is Lagoon Nebula (M8), a large interstellar cloud emission nebula.
Dark nebulae, non-luminous clouds of obscuring material that block light from stars behind them, are often overlooked simply because they themselves are sources of obscurity. In the eyepiece, they look like dark patches where there are no stars, but are in fact vast intervening dust clouds. These, too, get designations such as The Pipe Nebula and Lynds Dark Nebula 1773.
The moon, which will be the largest of the year, is full at 12:09 p.m. Aug. 10, and is called the Full Red or Full Sturgeon Moon.