July's Observing Highlights: Jupiter in the Morning, Venus at Night
That bright light skimming the western horizon in July is Venus, a planetary floodlight shining at magnitude -3.9. The closest planet to Earth is a fat gibbous seen through binoculars but will brighten over the coming months even as its phase shrinks because it draws nearer to us in its orbit. It won't reach its peak brightness of -4.9 until December, however.
Two observing challenges in early July include Venus in the Beehive Cluster on July 3 and the moon below Venus on July 9. Both events occur so close after sunset that the remnant light will wash out most of the cluster's stars and the moon’s thin crescent.
By July 10, the slightly larger crescent moon will be easier to spy and Venus will be to the upper right, with the star Regulus to the upper left. At magnitude 1.3, Regulus is the brightest star in Leo the Lion and is found at the bottom of the constellation’s backward question mark shape. On July 11, Regulus is to the upper right of the moon.
Meanwhile, back in the west-northwest, Venus has been inching its way toward Regulus. Look for the pair over the weekend of July 20, when they will be two degrees apart, and on July 21 and 22 the duo lie just over one degree from each other.
For early risers, July allows you to spot Jupiter and Mars. On July 6, catch the old crescent moon rising just before the sun in the east near Mars and Jupiter. Jupiter and Mars will move closer together over the course of the month, and on July 22 and 23 the pair will be less than a degree apart. Look east-northeast to see the solar system neighbors as they lie in Gemini, with bright Jupiter at magnitude -1.9 to the right and reddish Mars at magnitude 1.5 to the left.
Earth reaches aphelion, or its farthest point from the sun in its orbit around our star, on July 5 at 11:59 a.m. PDT. The Earth will be 1.0167 Astronomical Units from the sun on that date.
July’s Full Moon is sometimes called the Buck Moon or Thunder Moon. The moon reaches full phase on July 22 at 11:15 a.m. PDT. It will rise in the constellation Capricornus that evening as it is already beginning to wane.
A subtle meteor shower known as the Delta Aquarids peaks over the weekend of July 27. The shower will be best before dawn, with up to 10 meteors an hour possible.
(Photo: The Beehive Cluster, Venus, and the Moon was taken in 2012 by John Chumack.)
Kelly Kizer Whitt loves clean, clear, and dark skies. Kelly studied English and Astronomy at the University of Wisconsin-Madison and worked for Astronomy magazine. She writes the SkyGuide for AstronomyToday.com. You can follow her on Twitter at twitter.com/Astronomommy.