For April 2025 the waxing crescent moon passes just north of Jupiter on April 2nd. On April 4th, the first quarter moon passes just above Mars. The full moon, the Egg Moon, is on April 12th. The moon is last quarter on April 20th. In the dawn on April 24th, the waning crescent moon lies just to the left of bright Venus and below it, fainter Saturn; it lies to the right of the pair the following dawn, and just to upper right of Mercury near the horizon. The new moon is April 27th, and on the 30th, the waxing crescent again passes by bright Jupiter at dusk.
At the start of March, Mercury and Venus lay in the west after sunset. Now both have passed between us and the Sun into the dawn sky. Venus is brilliant in the dawn as April begins, just north of much fainter Saturn. Venus is at its brightest on April 27th. Mercury joins the pair at month’s end.
Still in the evening sky, Jupiter is well up in west after sunset as April begins, but much lower by month’s end. Mars is higher in the sky, in Gemini, and will stick around in the evening sky until the end of summer.
While the naked eye, dark adapted by several minutes away from any bright lights, is a wonderful instrument to stare up into deep space, far beyond our own Milky Way, binoculars are better for spotting specific deep sky objects. For a detailed map of northern hemisphere skies visit the www.skymaps.com website and download the map for April; it will have a more extensive calendar, and list of best objects for the naked eyes, binoculars, and scopes on the back of the map Also available is wonderful video exploring the April sky, available from the Hubble Space Telescope website at: www.hubblesite.com. Sky and Telescope has highlights at www.skyandtelescope.com/observing.
Yellow Capella, a giant star the same temperature and color as our much smaller Sun, dominates the northwestern sky. It is part of the pentagon on stars making up Auriga, the Charioteer (think Ben Hur). Several nice binocular Messier open clusters are found in the winter milky way here. East of Auriga, the twins, Castor and Pollux highlight the Gemini. South of Gemini, Orion is the most familiar winter constellation, dominating the southern sky at dusk.
The reddish supergiant Betelguese marks his eastern shoulder, while blue-white supergiant Rigel stands opposite on his west knee. Just south of the belt, hanging like a sword downward, is M-42, the Great Nebula of Orion, an outstanding binocular and telescopic stellar nursery. The bright diamond of four stars that light it up are the trapezium cluster, one of the finest sights in a telescope. In the east are the hunter’s two faithful companions, Canis major and minor. Procyon is the bright star in the little dog, and rises minutes before Sirius, the brightest star in the sky. At 8 light years, Sirius is the closest star we can easily see here.
To the northeast, look for the Big Dipper rising, with the top two stars of the bowl, the pointers, giving you a line to find Polaris, the Pole Star. Look for Mizar-Alcor, a nice naked eye double star, in the bend of the big dipper’s handle. Take the pointers at the front of the dipper’s bowl south instead to the head of Leo, looking much like the profile of the famed Sphinx.
The bright star at the Lion’s heart is Regulus, the "regal star". Now take the curved handle of the Big Dipper, and follow the arc SE to bright orange Arcturus, the brightest star of the spring sky. Studies of its motion link it to the Sagittarius Dwarf Galaxy, a companion of our Milky Way being tidally disrupted and spilling its stars above and below the plane of the Milky Way, much like dust falling away from a decomposing comet nucleus. So this brightest star of Bootes the Bear Driver is apparently a refugee from another galaxy, but now trapped by our Galaxy’s gravity.
Now spike south to Spica, the blue-white gem in Virgo rising in the SE. Virgo is home to many galaxies, as we look away from the obscuring gas and dust in the plane of the Milky Way into deep space. To the southwest of Spica is the four sided Crow, Corvus. To the ancient Greeks, Spica was associated with Persephone, daughter of Ceres, goddess of the harvest. She was abducted by her suitor Pluto, carried down to Hades (going to Hell for a honeymoon!) and when Jupiter worked out a compromise between the newlyweds and the angry mother-in-law, the agreement dictated Persephone come back to the earth’s surface for six months of the year, and Mama Ceres was again placated, and the crops could grow again.
As you see Spica rising in the SE, it is time to "plant your peas", and six months from now, when Spica again disappears in the sun’s glare in the SW, you need to "get your corn in the crib"….so was set our calendar of planting and harvesting in antiquity. There is indeed a rich harvest in Virgo, of galaxies. Between Spica and Corvus is M-104, the famed "Sombrero".
