Moon to sweep by Jupiter and star Antares
From around the world on the evenings of June 14, 15 and 16, 2019, look for the moon and then for the red supergiant star Antares and the giant gas planet, Jupiter. The moon – now in a waxing gibbous phase, moving toward full moon on the night of June 16-17 – will pass to the north of Antares and Jupiter.
Despite the moon’s glare, you should be able to see Antares and Jupiter relatively easily. Antares counts as a 1st-magnitude star, and Jupiter is far brighter than any star (except our sun), outshining Antares by nearly 30 times. Remember, though, that Antares, being a star, shines by its light. Jupiter shines only by reflecting sunlight.
As the Earth spins beneath the heavens, moving from west-to-east on its rotational axis, the moon, Antares and Jupiter will appear to parade westward across the sky throughout the night. However, this supposed motion of the moon, Antares and Jupiter is really a reflection of the Earth spinning on its rotational axis.
What’s more, even as the moon goes westward throughout the night, it’s simultaneously moving eastward in front of the stars and bright planets of our solar system. Throughout the night, the moon moves about 1/2 degree (its own angular diameter) eastward in front of the constellations of the zodiac. In one day (24 hours), the moon journeys some 13 degrees eastward upon the zodiac.
