The Moon stages some especially close encounters with several stars and planets this month. It teams up with Saturn and Mars in the dawn sky, along with Neptune, which is too faint to see with the eye alone. Mercury creeps in there as well, but it’s difficult to spot. The Moon snuggles especially close to Antares, the bright orange heart of the scorpion, near month’s end. The Summer Triangle begins to climb into the evening sky, along with Libra, the balance scales, a lead-in to the prominent summer constellation Scorpius. On the other hand, Leo, the lion, plunges head first toward the southwestern horizon.
The full Moon of May is known as the Milk Moon, Flower Moon, or Corn Moon.
Perigee May 5
Apogee May 17
Moon phases are Central Time.
Summer begins tonight in the northern hemisphere, when the Sun stands farthest north for the year — a moment known as the summer solstice. The season lasts until the September equinox, when the Sun crosses the equator from north to south.
Venus, the brilliant “morning star,” will stand to the left of the Moon at first light tomorrow, and about the same distance to the upper right of the Moon on Wednesday.
Summer arrives on Tuesday night, with the summer solstice. Tuesday and Wednesday will be the longest days of the year here in the United States — the greatest intervals between sunrise and sunset.
The timekeeper for the United States, the Naval Observatory, defines sunrise and sunset as the moments when the center of the Sun is physically 50 minutes of arc below the horizon, which is less than the width of your finger held at arm’s length.
Hydra, the water snake, slithers quite low across the southwest at nightfall. One of its treasures is the binary system V Hydra. Its main star is old and puffed up. It expels gas into space, which the second star grabs, then shoots out like cannonballs.
The last gasp of a dying star climbs the eastern sky on June evenings. The Ring Nebula is not far to the lower right of the brightt star Vega, which is about halfway up the sky as night falls. The nebula consists of the ejected outer layers of a once-normal star.
Hercules and Ophiuchus are in the east this evening. Hercules is named for the Greek hero, while Ophiuchus, the serpent-bearer, is named for the mythological founder of Greek medicine. Both joined Jason aboard the Argo in search of the golden fleece.
Altair, one of the closest and brightest stars in the night sky, is in good view on June evenings. It forms the southern point of the Summer Triangle, which is low in the east and northeast at nightfall, and wheels high across the sky during the night.
The planet Saturn is putting on its best showing of the year this week. It’s low in the southeast as night falls and looks like a bright gold star. It arcs across the south later on, and remains in view all night.
The star cluster Messier 5 stands high in the southeast at nightfall, far to the lower left of Arcturus, a bright yellow-orange star. Through binoculars, M5 looks like a fuzzy star. Small telescopes reveal some of its individual stars.
