What Some Tourists Leave Behind

You won’t mind picking up after comet Tempel-Tuttle

The young crescent moon appears in the southwest at twilight Thursday and Friday, with ruddy Mars a half-dozen degrees to the east the first night and to the southwest the next. Through the weekend the waxing moon sets well before midnight, providing a dark backdrop for the annual Leonid meteor shower.
    This year’s Leonids should be most active before dawn Saturday, November 17, but you might well see meteors a couple days before and after. The meteors look as if they come from the constellation Leo, which rises around 1am, arcs up and to the west to stand high in the south around 6am. As a rule of thumb, the higher Leo is in the sky, the more meteors you’re likely to see.
    Each year around this time in its orbit around the sun, Earth crosses the path of another orbiter, comet Tempel-Tuttle. Like a bad tourist, comets leave a mess in their wake, tiny bits of dust, dirt and ice. As Earth plows through this trail of debris, the pieces hitting our atmosphere burst into flames. Some years, Earth’s crossing point is more densely riddled with debris, leading to more meteors.
    The Leonids follow a pretty predictable 33-year cycle. The last big meteor storm — with upward of 100 an hour — was in 2001. This year, with clear skies you can expect to see roughly a dozen meteors an hour and maybe a burst of 20 or more at a peak hour. The Leonids are fast-moving, crossing the celestial dome in the blink of an eye.
    While you’re looking for meteors, Jupiter will keep you company. Rising an hour after sunset, Old Jove is high in the south at 1am and above the western horizon a couple hours before dawn. At that time, brighter Venus is rising in the east and climbing fast. This so-called Morning Star passes the actual star Spica the morning of the 18th and then sets its sights on Saturn, just now escaping the sun’s glare. Watch the two planets close the gap over the next 10 days.