You are here

In the Sky This Month

The stars of winter are marching toward the end of their annual evening run. Orion is in the southwest at nightfall as April begins, for example, but is quite low in the west as the Sun begins to set by month’s end. Sirius, the Dog Star, is to the lower left of Orion. It’s the brightest true star in the entire night sky, so even though it’s quite low, it sparkles beautifully as it drops from view in the evening for another year.

April 12: Spring Stars

Three of the “stars” of spring are climbing higher into the evening sky. Around 10 p.m., look high in the south for Regulus in Leo, the lion. Spica, in Virgo, is in the east-southeast, with yellow-orange Arcturus well to its upper left in Bootes, the herdsman.

April 13: Sirius

Under a dark, clear sky, you may see a couple of thousand stars. The brightest is Sirius, which is well up in the south-southwest in early evening. The faintest stars visible to the unaided eye are only about one one-thousandth as bright as Sirius.

April 14: T Pyxidis

A star in the system T Pyxidis is taking gas from a companion star. Every few decades it erupts, blasting away more of the companion, so the companion could disappear. The system is low in the south at nightfall. You need a telescope to see T Pyxidis.

April 15: Moon and Aldebaran

Aldebaran, the bright orange eye of Taurus, the bull, accompanies the Moon down the western sky this evening. It stands close to the left of the Moon and is easy to pick out.

April 16: Moon and Mars

Mars follows the Moon down the sky this evening. The planet looks like a fairly bright orange star to the upper left of the Moon. A similarly bright star, El Nath, stands about the same distance to the upper right of the Moon.

April 17: More Moon and Mars

The Moon and Mars drop down the western sky this evening. They are high in the sky at nightfall, with Mars, which looks like a fairly bright star, to the lower right of the Moon. They set by 1 or 2 a.m.

April 18: Hunting Dogs

Canes Venatici, the hunting dogs, is high in the east as night falls. The constellation represents two dogs held on a leash by Boötes, the herdsman. Canes Venatici is well to the upper left of bright yellow-orange Arcturus, the brightest star of Boötes.

Last quarterLast Apr. 4, 5:02 pm

New MoonNew Apr. 11, 9:31 pm

First QuarterFirst Apr. 20, 1:59 am

Full MoonFull Apr. 26, 10:32 pm

Times are U.S. Central Time.

Apogee April 14

Perigee April 27

The full Moon of April is known as the Egg Moon or Grass Moon.