In the Sky This Month

June offers warm nights for watching the sky but a limited amount of time to enjoy the view, with the longest days and shortest nights of the year. Even so, there is plenty to look at, with Leo diving toward the western horizon in early evening and the Summer Triangle climbing into view in the east. The triangle’s leading light, Vega, is the second-brightest star visible from most of the United States on summer evenings, only a fraction fainter than Arcturus, which is high in the south at nightfall.

June 27: Moon and Regulus

The star Regulus perches just a whisker away from the crescent Moon this evening. It’s the leading light of Leo, the lion. The name Regulus means “the little king.” The star is also known as Alpha Leonis, 32 Leo, and more than a dozen other names.

June 28: Sagittarius Rising

Sagittarius climbs low across the southern sky on summer nights. Its brightest stars form the shape of a teapot, which clears the southeastern horizon a couple of hours after sunset. The center of the Milky Way galaxy is above the teapot’s spout.

June 29: Future Fireworks

Cygnus, the swan, soars across the east at nightfall. One of its stars may explode around 2022. The system’s two stars are spiraling closer together. They should merge, causing an outburst that will make the system one of the brightest in the night sky.

June 30: Moon and Jupiter

The Moon has a big companion tonight, the planet Jupiter. It looks like a brilliant star quite close to the left of the Moon. Jupiter is the largest planet in the solar system — about 11 times the diameter of Earth.

July 1: Moon and Companions

The Moon is in the southwest as night falls this evening, with two bright companions. The star Spica stands below the Moon, with the brilliant planet Jupiter a little farther to the right or lower right of the Moon.

July 2: Tezcatlipoca

The Big Dipper is visible every night of the year, circling the North Star, Polaris. To the Aztecs, the dipper personified the god Tezcatlipoca, “He Who Can Enter All Places.” He reigned over the cardinal directions as well as the night.

July 3: Far from the Sun

Earth is farthest from the Sun today for the entire year, a point in our planet’s orbit known as aphelion. We’re about 1.5 percent farther than the average distance of 93 million miles.