by Sean O’Dwyer
The top six astronomical events for 2012 are easily visible from the Hudson Valley, with no special equipment required.
JUPITER & VENUS DOUBLE-PLANET
No need to beware these Ides of March. The Earth is zipping round the back of the sun, leaving Venus and Jupiter in its wake and, after sunset, both planets are visible in the western sky, just three degrees apart. (In fact, as the two brightest planets, you may be able to spot them during dusk.) Jupiter is farther from the sun than the Earth is, so it’s never “in phase”—that is, we never see a crescent Jupiter. However, Venus is closer to the sun than the Earth is, and mid-March will be close to quarter-Venus (clearly visible in a small backyard telescope). On March 25 and 26, the crescent moon slips by to enrich the double-planet scene.
THE BIGGEST FULL MOON
The moon will be closest to the Earth at 11:59pm on May 5, just 221,801 miles from home. (If Interstate 87 extended to the moon, and you followed the speed limit of 65mph for 24 hours a day, you could drive there in just 142 days.) When the moon is so close, it affects tides even more than usual, making low tides exceptionally low and high tides exceptionally high.
VERY RARE TRANSIT OF VENUS ACROSS THE FACE OF THE SUN
This was a huge public hit when it last happened in 2004, and that date is so recent you might think this happens all the time. Not so. The next previous time we humans were able to observe this phenomenon was in 1882. Before that, it was seen a total of only four times by human eyes, and the next transit won’t occur until 2117! So this is it for me and you and everyone we know. As with a solar eclipse, or any time you’re viewing the sun, viewers are warned to take all the necessary precautions when looking at the sun. In the Hudson Valley, the transit will start around 5:10pm as Venus starts to creep onto the northern edge of the sun’s disc. The event will be visible, weather permitting, until the sun sets around 7:23pm.
PERSEID METEOR SHOWER
The Perseids are tiny grains of dust and dirt from the comet Swift-Tuttle, the nucleus of which is about six miles across—similar in size to the object that killed off the dinosaurs. Swift-Tuttle is due to return to the inner solar system in 2126 but, no, it won’t hit us. Usually the year’s strongest shower, the Perseid’s typical maximum rate is 30 to 70 meteors per hour—though sometimes it’s much higher. Meteors are typically just grains of sand from comet tails ripping through the upper atmosphere at 44 miles per second, where they heat up to more than 3,000°F. A few are as big as peas or marbles. Being too fast, short-lived, and unpredictable, meteors are best viewed with the naked eye, wrapped in a warm blanket. In 2011 the moon was bright, obscuring the shower’s fainter streaks, but this year the moon will be past last quarter, causing no loss of viewing awesomeness.
DECEMBER 13th - 14th:
GEMINID METEOR SHOWER
The Geminids are the most reliable shower of the year, producing bright, colorful, moderately swift meteors that sometimes break apart as fireballs. The shower is thought to be intensifying every year and recent showers have seen 120 to 160 meteors per hour under optimal conditions. In fact, most meteor experts now put the Geminid shower at the top of the year’s list, surpassing even the Perseid shower. The best viewing time is in the early hours, around 2 to 3am, when the Geminid is almost directly overhead. (This is because, as the Earth spins, the side facing the direction of its orbit around the sun scoops up more debris.) But any time after dark is good. Just make sure you wrap up warm.
THE MOON AND JUPITER
Visible in the east right after dark, and less than half a degree to the northwest, giant Jupiter hovers brilliantly over the waxing gibbous moon. Binoculars will allow you to easily pick out Jupiter’s four largest moons, from west to east: Europa, Io, Ganymede, and Callisto. And a moderately powerful telescope will show Io’s shadow trailing behind as it transits Jupiter’s cloud tops.