If we’re lucky, Comet ISON will become faintly visible in the predawn sky this week. But comets are notoriously unpredictable, so nobody can say for sure what will happen.
The ancient constellations of the Great Sea fill the southern sky, from Cetus the Sea Monster to strange Capricornus the Sea Goat, whose origin is lost in the mists of time.
Look to the right of Cassiopeia for a formation that I call the Really Big Dipper. It’s composed of the three brightest stars of Andromeda together with the Great Square of Pegasus.
The Perseus constellation group fills the northeastern sky. The W of Queen Cassiopeia is most striking. Her son-in-law Perseus below is home to one of the sky’s best but least-known star clusters.
Dazzling Venus creeps through Scorpius, passing a short distance above the strikingly red star Antares. And in the predawn sky, Mars passes slightly farther from Regulus, the brightest star of Leo.
Venus passes the star Delta Scorpii this week. In June 2000, Argentine stargazer Sebastián Otero caught Delta in a midlife crisis, changing from a normal star to one that varies in brightness.
Jupiter, the king of the planets, passes extraordinarily near the star Wasat in the sky. Although they appear close together, they’re actually totally different kinds of objects at wildly different distances from Earth.
You can view the change of seasons in the evening sky. The signature constellations of summer are setting in the west, while bright Cassiopeia, Perseus, Andromeda, and Pegasus rise in the northeast.
Autumn begins on Sunday, September 22nd. The full Moon closest to this date, called the Harvest Moon, rises just before sunset on Wednesday and sets just after sunrise on Thursday.
The waxing Moon traverses the sky this week. If you want a great project, track its appearance each night as it changes from 20% to 85% lit. Remarkably, we always see the same side of the Moon.
The Moon pairs with Mars early on Monday morning, and it’s spectacularly close to Venus at dusk on the following Sunday. In between, Venus passes a finger’s width above the bright star Spica.
Deneb, the faintest star of the Summer Triangle, belongs to the magnificent constellation Cygnus, the Swan, which flies along the Milky Way. Cygnus’s brightest stars form the splendid Northern Cross.
Vega, the brightest star of the Summer Triangle, is almost overhead now. Together with five fainter stars, Vega forms the strikingly geometric constellation Lyra, the Lyre.
The Perseid meteor shower winds down this week. Learn about the different kinds of meteoroids, and what happens on the rare occasions when they strike Earth’s surface.
The Perseid meteor shower is ramping up this week, reaching its strongest from midnight on Sunday, August 11th, to dawn’s first light the next morning.
The Milky Way band is one of nature’s most magnificent sights. But most Americans are unable to see it because of the creeping blight of light pollution.
Two fine constellations are side by side in the south: hook-tailed Scorpius and Sagittarius, the Archer. The center of our Milky Way galaxy lies behind the stars of Sagittarius.
Three spectacularly close approaches take place in the heavens this week. The Moon meets the stars Spica and Zubenelgenubi, and Venus passes close to Regulus.
Magnificent Scorpius is near its highest at nightfall. This is one of the few constellations that really resembles its name. Antares, its chief star, is strikingly bright and red.
Days are long and nights are short during the first full week of summer. Learn how summer is defined in astronomical terms, and why it matters to all life on Earth.
As the sky grows dark in the evening, the stars of the Summer Triangle are rising in the east: Vega in the constellation Lyra, Altair in Aquila, and Deneb in Cygnus the Swan.
This week features a close pairing of Mercury and Venus, the beginning of summer, and the largest and closest full Moon of the year.
A beautifully thin crescent Moon forms a triangle with Mercury and Venus after sunset on Monday. Then Venus appears a little higher each evening and Mercury a little lower.
This is the best week in 2013 to view Mercury, the elusive innermost planet. And find out how the quasar 3C 273 was first discovered.
The planets Venus, Jupiter, and Mercury form an amazingly tight triangle by the end of this week. This is the closest conjunction of three bright planets until January 2021.