The sky in June

Mercury is easy to find at dusk as June begins. Look for it about twenty-two degrees to the lower right of Venus (the width of your fist held at arm's length is roughly ten degrees across the sky). Mercury appears at magnitude +0.5 and sets just before the end of evening twilight. On the 2nd it reaches its greatest eastern elongation, or apparent angular separation from the Sun: twenty-three degrees. The planet is still as much as fifteen degrees above the horizon at sunset. A week later, on the 10th, it sets an hour and a half after the Sun, but by then it is also much dimmer, appearing at magnitude +1.5. From then on the planet fades rapidly. It passes inferior conjunction, roughly in line between Earth and the Sun, on the 28th.

Venus is by far the most brilliant evening "star" in the west after sunset. Sharp-eyed observers might even pick it out a little north of due west as the Sun sets. The interval between sunset and Venus-set shrinks from more than three hours at the start of the month to less than two and a half hours by month's end. In a telescope the planet is rapidly waning even as it grows in size, the telltale signs that Venus is swinging toward us along its orbit. Meanwhile, the planet is brightening by some 30 percent, reaching magnitude -4.5 by early July.

By pure geometry, Venus should appear half illuminated on the 9th, when it reaches its greatest elongation from the Sun. But its actual observed half phase, or "dichotomy," will likely appear some days earlier, though nobody knows exactly why. Thereafter Venus becomes a crescent that noticeably thins and lengthens. On the evening of the 18th a slender crescent Moon appears to hover almost midway between Venus (to its lower right) and Saturn (to its upper left). And at the end of the month Venus itself has a close encounter with Saturn (described under "Saturn").

Mars rises before 3 A.M. local daylight time on the 1st and an hour earlier than that by the 30th. Throughout the month it races eastward against the stars, crossing from the constellation Pisces, the fish, into the constellation Aries, the ram, on the 27th. Mars is the bright orange "star" below and to the right of the Great Square of the constellation Pegasus, the winged horse, as dawn breaks at the start of the month. For the rest of the month it lies well below the stars of the constellation Andromeda, the chained princess.

Jupiter, glaring regally at magnitude -2.6, passes opposition to the Sun on the night of the 5th. After Venus sets, it is by far the brightest starlike object in the sky. It dominates the southeast during the early evening. Then, accompanied by the stars of the constellation Scorpius, the scorpion, with its ruddy heart, Antares, this magnificent planet treks across the southern sky all night before setting around dawn. But even at a respectably bright magnitude of +1.1, Antares is only about a thirtieth as bright as Jupiter.

Saturn lies in the constellation Leo, the lion, and appears in the western sky at dusk at magnitude +0.5. On the 1st, the planet sets more than four hours after the Sun; by the 30th, Saturn sets soon after evening twilight ends. Late in the month Venus, a hundred times brighter than Saturn, approaches from the west, coming within about three-quarters of a degree directly below the ringed planet on the 30th.

The Moon is at last quarter on the 8th at 7:43 A.M. It wanes to its new phase on the 14th at 11:13 P.M. and waxes to first quarter on the 22nd at 9:15 A.M. The June full Moon, sometimes called the "Strawberry Moon," takes place on the 30th at 9:49 A.M.

The solstice takes place on the 21st at 2:06 P.M. Summer officially begins in the Northern Hemisphere, winter in the Southern Hemisphere.

Unless otherwise noted, all times are eastern daylight time.

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