Moon and Venus
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.
Approaching Summer
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.
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.
Big Changes
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.
Planetary Nebulae
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.
Argonauts
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
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.
Saturn at Opposition
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.
Messier 5
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.
On the Move
Earth orbits the Sun at about 67,000 miles per hour. The solar system, in turn, orbits the center of the Milky Way galaxy at about 500,000 mph. And the Milky Way is moving toward a giant cluster of galaxies at 1.3 million mph.