This week, Mercury appears just a few degrees from Venus in the sky. // NASA/JHUAPL/CIW

Friday, June 14
The two inner planets remain companions in the early evening sky all week. Look low in the west-northwest as darkness falls and you can’t help but see brilliant Venus. From mid-northern latitudes, it stands close to 10° high 45 minutes after sunset. Dimmer Mercury, which reached greatest elongation and peak visibility just two days ago, appears nearly 4° to Venus’ upper left tonight. You’ll get your best view of this planetary duo through binoculars.

Saturday, June 15
Look high in the northwest after darkness falls this month, and you will see the familiar sight of the Big Dipper. The Dipper is the most conspicuous asterism — a recognizable pattern of stars that doesn’t form a complete constellation shape — in the entire sky. It forms the body and tail of Ursa Major the Great Bear. Use the Pointers, the two stars at the end of the Dipper’s bowl, to find Polaris, which lies due north for everyone north of the equator. Polaris marks the end of the Little Dipper’s handle. On June evenings, the relatively faint stars of this dipper arc directly above Polaris.

Spring's best comet fades in June, but it remains visible all night from mid-northern latitudes as it slices through Ursa Minor. // Astronomy: Roen Kelly

Sunday, June 16
You can find the First Quarter Moon well above the southwestern horizon as darkness falls. Our satellite officially reaches First Quarter phase at 1:24 p.m. EDT, so it appears slightly more than half-lit from North America this evening. It sinks toward the western horizon throughout the night before setting around 1 a.m. local daylight time. The Moon spends the evening among the background stars of western Virgo.

Monday, June 17
Comet PANSTARRS (C/2011 L4) should glow around 9th magnitude this week, and you’ll need a telescope to follow its trek back into the solar system’s depths. Fortunately, it remains on view all night for observers in the Northern Hemisphere. For the next few evenings, it lies within 1° of the 2nd-magnitude star Beta (β) Ursae Minoris. Beta is the brighter of the two stars that form the end of the Little Dipper’s bowl. Use the instructions from June 15 to locate this dipper.

It's always a challenge to see Mimas and Enceladus near Saturn's rings, but viewers have a good opportunity the night of June 18/19. The planet's other bright moons conveniently lie nearby. // Astronomy: Roen Kelly

Tuesday, June 18
Saturn shines at magnitude 0.4 among the background stars of eastern Virgo. It reaches its maximum altitude in the south around 9:30 p.m. local daylight time and doesn’t set until well after midnight. Although the planet looks attractive enough with naked eyes, it doesn’t dazzle until you view it through a telescope. Even a small instrument reveals Saturn’s 18"-diameter disk and the spectacular rings, which currently span 41" and tilt 17° to our line of sight. Tonight also offers a great opportunity for those with larger scopes (10 inches or more in aperture) to spy the planet’s fainter moons. Both 12th-magnitude Enceladus and 13th-magnitude Mimas reach greatest eastern elongation and peak visibility within a half-hour or so of each other. Several brighter moons, including the 8th-magnitude giant, Titan, complete the impressive scene.

Wednesday, June 19
Jupiter passes behind the Sun from our perspective, a configuration astronomers call conjunction, at noon EDT. (Our star actually occults the planet, an occasion that comes around twice during Jupiter’s 12-year orbit.) Needless to say, the Sun’s glare makes it impossible to see the planet. Jupiter will return before dawn in July.

Ceres, the largest asteroid, crosses into Cancer this week. // Astronomy: Roen Kelly

Thursday, June 20
Mercury and Venus appear closest to each other in this evening’s twilight sky. Innermost Mercury slides 2° south (to the lower left) of its neighbor and shows up easily through binoculars, though it might be a challenge to see with naked eyes. Mercury glows at magnitude 1.2 — 100 times fainter than magnitude –3.8 Venus. A wide-field telescope shows both planets together. Mercury appears 10" across and 23 percent illuminated. Venus displays a fat gibbous disk just 1" wider than its sister world.

Friday, June 21
Earth’s summer solstice occurs at 1:04 a.m. EDT (10:04 p.m. PDT on June 20), when the Sun reaches its farthest point north in the sky. This marks the official beginning of summer in the Northern Hemisphere, and the day of the solstice has more hours of sunlight than any other. From mid-northern latitudes, however, the earliest sunrise occurred about a week ago and the latest sunset won’t happen until next week.

Saturday, June 22
You won’t have too many more chances to spy asteroid 1 Ceres in the evening sky this year. The magnitude 8.8 object lies on the border between Gemini and Cancer tonight, slightly less than 2° southwest of the 5th-magnitude star Chi (χ) Geminorum. This region stands only about 5° high in the northwest near the end of evening twilight. You’ll need a telescope to spot this solar system wanderer.

Sunday, June 23
Full Moon arrives at 7:32 a.m. EDT. Coincidentally, our satellite reaches perigee, the closest point in its orbit around Earth, just 20 minutes earlier. It then lies 221,824 miles (356,991 kilometers) away from us, its closest approach of the year. That makes this the largest Full Moon (33.5' across) of 2013. From North America, our satellite appears nearly Full against the backdrop of Sagittarius both Saturday and Sunday nights.