GARRETT COUNTY SKIES
By Dr. Bob Doyle, Frostburg State Planetarium
Sun & Moon in July: The sun appears in front of the star group Gemini for the first 19 days of July, then moves into Cancer of July 20. This means that both the star groups Gemini and Cancer will be lost in the sun’s glare this month. East of Cancer is Leo, where the planet Jupiter shines. So when you look in the West during evening twilight, you will see the stars of Leo and the bright planet Jupiter. (Bear in mind that the sun is really not moving; it’s the Earth’s motion about the sun that makes the sun appear to move eastward along the zodiac, usually carrying itself into a different zodiac group each month.) On July 4, the Earth reaches its farthest distance from the sun for the year at a distance of 94.5 million miles. Last January 2, the Earth was closest to the sun for the year at a distance of 91.5 million miles. The reason for this paradox (Sun being closest when it’s cold and Sun being farthest when it’s warm) is that the tilt of the Earth’s axis is the cause of the seasons. In early summer, our north polar axis is tipped towards the sun, causing the sun to appear higher and shine longer. In early winter, our north polar axis is tipped away from the sun, leading to a low sun path across the sky and a shorter daily ration of sunlight. Early July opens with a slender crescent moon in the eastern dawn. Then on July 4, the moon swings from the morning to the evening side of the sun (New Moon). Then a few days after July 4, a slender crescent moon will be see low in the western twilight. The moon will appear North of (above) the star Regulus of Leo on July 8th and North of (above) the planet Jupiter on the 9th.
On July 12, the evening moon will appear half full (like a tilted letter ‘D’) with optimal viewing for the moon’s craters and mountain ridges. For along the straight edge of the moon, the sun there is rising,
lighting up the crater rims and mountain peaks. On July 14, the moon will pass North of the planet Saturn. The moon will be full on July 20. Just as last month’s full moon, this full moon will have a low track across the night sky. Low in the sky means the moon will be shining through much more air, filtering out the blue and green light, making the moon look yellowish. On July 26, the moon will appear half full in the southern dawn, appearing as a reversed ‘D’.
Planets in July: At the end of July, the planet Mercury may be seen low in the western dusk. Venus, which passed by the sun in early June is too low in the West after sunset to be easily seen. Mars is bright, low in the southern evening sky. You may even see its orange hue. Jupiter is the brightest point of light in the western sky as it get dark. The planet Saturn lies to the East or left of Mars. Saturn, which some people see as crème colored, is not as bright as Mars. But as all bright planet, Saturn shines with a steady light, unlike the twinkling stars.
PreDawn Skies in July: With the sun being either in Gemini or Cancer, the star group to west of Gemini is Taurus, the Bull. Thus as it begins to get light at dawn, Taurus will be in the East. Taurus’ two most striking features are the 7 Sisters star cluster and the bright star Aldebaran, marking an eye of the Bull.
In the North, the Big Dipper floats parallel to the horizon. The Dipper’s two rightmost stars point up to the North Star, a modest star about halfway up in the North. In the Northeast, shines the bright golden star Capella, visible in the evening sky from the fall, winter and spring seasons.
There will be a free public planetarium program on July 9 at 8 p.m. at the Frostburg State Planetarium in Room 186 of the Gira Center. Weather permitting, telescopes will be set up outside for viewing of the moon and planets. If readers of this column have any space questions, email me at firstname.lastname@example.org .