On July 6, 2014, the moon shines to the east of the star Spica and planet Mars, and is heading toward the planet Saturn. It’ll be close to Saturn on July 7. Right now, Saturn is between two stars that represented a celestial gateway to the early stargazers, the stars Zubenelgenubi and Zubeneschamali in the constellation Libra. These two Libra stars were seen as a gateway on the sky’s dome because planets sometimes pass between them. And, at certain times in the moon’s 18.6-year cycle, the moon passes in between Libra’s two brightest stars on a monthly basis.
In fact, if you watch each month, you’ll see the moon in its monthly sweep farther and farther north of Zubenelgenubi for the next several years.
Each day, the moon shifts farther and farther east, with respect to the stars and planets. The moon moves toward the east on our sky’s dome continually. This motion is a translation on our sky’s dome of the moon’s orbit around Earth.
On the night of July 7, 2014, you’ll see the moon close to the planet Saturn. In fact, if you live in southern South America, you might even see the moon occult – cover over – Saturn – sometime on July 7.
Most of us won’t see the occultation of Saturn. But we all can observe the moon’s orbital motion from one night to the next, by watching the moon’s location with respect to background stars.
Or, try looking outside each evening at the same time to notice that the moon is in a more easterly location on the sky’s dome than it was the night before. Just remember, when you do this, you’re actually observing the moon moving in its orbit around Earth.
First quarter moon took place on July 5 at 11:59 Universal Time. The July 6 moon is at the waxing gibbous phase. A waxing giboous moon carries that designation because it is more than half illuminated but less than full. The terminator – or shadow line dividing the lunar day from the lunar night – shows you where it’s sunrise on the waxing moon. That line will be slightly curved on the July 6 waxing gibbous moon.
Bottom line: The moon on July 6, 2014 is between two sets of objects – on one side, the star Spica and planet Mars – and on the other side, the planet Saturn. Note the wonderful contrast of color between sparkling blue-white Spica, the red planet Mars and the golden planet Saturn. Although you might be able to see these colors with the eye alone, binoculars make the color contrast more apparent. Also in this post, an explanation of the moon’s relationship to the two Libra stars, Zubenelgenubi and Zubeneschamali. These two stars have been known as a celestial gateway in times past.