2025, May 16: At Summer’s Doorstep

May 16, 2025: Stars that appear in the eastern sky after sundown, indicate the summer season is near.

Mars, Moon and Antares, January 21, 2020
Photo Caption – 2020, January 21: Mars is near Antares with the crescent moon nearby.

by Jeffrey L. Hunt

Chicago, Illinois: Sunrise, 5:29 a.m. CDT; Sunset, 8:05 p.m. CDT.  Check local sources for sunrise and sunset times. Times are calculated by the US Naval Observatory’s MICA computer program.

Related Articles

Venus Summary Article
VENUS AS A MORNING STAR, 2025

May is one of the best months of the year for sky watching at the mid-northern latitudes. It has whipped the persistent cold winds of winter and early spring, though refreshing breezes from the northwest clear the sky.

Evening Sky

The Beehive or Praesepe star cluster (National Science Foundation Photo)
Photo Caption – The Beehive or Praesepe star cluster (National Science Foundation Photo).

This year, Jupiter is low in the west-northwest above a line that connects Taurus’ horns.  Mars is about halfway up in the west-southwest, east of the Beehive star cluster, which is easily visible from rural areas.

Sirius, Rigel, and Aldebaran have disappeared into western evening twilight. Betelgeuse is on the verge of mixing with the red and orange hues of evening’s light.  These magnificent stars that are prominent during winter evenings reappear in the eastern sky during summer.

Signs of Summer

Vega, Deneb, May 16, 2025
2025, May 16: Vega and Deneb, two stars in the Summer Triangle, are in the northeastern sky.

With the solstice more than five weeks away, summer’s stars are visible in the eastern sky after the end of evening twilight.  Begin the survey in the northeast.  Blue-white Vega, the brightest star in Lyra, is about one-third of the way up in the northeast.  Meaning “the falling eagle,” Vega is about 50 times brighter than the sun as it shines from 25 light years away.

Vega is the third brightest star visible from the mid-northern latitudes after Sirius and Arcturus.  It is the second brightest on the northern half of the sky.  The sky can be divided at the celestial equator, a circle in the sky above Earth’s equator.  Sirius is south of the equator.  Arcturus is the brightest star in the north.

Deneb, Cygnus’ tail, is nearly 15° above the northeast horizon and nearly 25° to Vega’s lower left. It shines with an intrinsic brightness of nearly 50,000 suns from a distance of 1,400 light years. Along with Alnilam, one of Orion’s belt stars and a few others, Deneb is one of the farthest individual stars to see without optical aid.

Vega and Deneb appear higher in the sky each evening.  As June opens Altair joins them above the east horizon.  The trio makes the Summer Triangle, which is visible in the eastern sky as night falls on solstice evening.

Scorpius in Southeast

Scorpius, May 15, 2025
Chart Caption – 2025, May 16: Two hours after sunset, Scorpius crawls across the southeastern horizon.

Tonight, farther southward, Scorpius reaches across the southeast horizon. Its claws, Zubeneschamali and Zubenelgenubi, reach westward from about 30° above the horizon.  The forehead, Dschubba, is less than 15° above the horizon.  Antares, the Scorpion’s heart, is over 5° above the horizon.

Antares is a large reddish star, near the end of its stellar life, according to stellar lifecycle models.  The star’s reddish color is from a core that is considerably hotter than the sun’s center.  The heat forced the star’s outer gaseous envelopes to expand, which cooled them.

During July, the Scorpion appears to crawl westward during the evening hours.

As the solstice approaches, watch the stars in the eastern sky appear higher at the same time.

RECENT PODCASTS

LATEST ARTICLES