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Clear with a Chance of Showers

Will the Boötids show or no?

Friday’s new moon provides a dark backdrop for the annual Boötid meteor shower, which peaks after sunset that night and before dawn Saturday. Most years the Boötids are a modest shower, topping out at a dozen meteors an hour. But every now and then, it storms.
    This meteor shower was first recorded in 1916, when English astronomer W. F. Denning counted more than 100 meteors an hour. “Large meteors came in quick succession from a radiant in the region between Boötes and Draco,” he wrote. Denning described them as “moderately slow, white with yellowish trains. … Several of the meteors burst or acquired a great intensification of light near the termination of their flights, and gave flashes like distant lightning.”
    Another storm came in 1921. Then, in 1926, the skies erupted, with an astronomer in Russia witnessing up to 500 shooting stars an hour. But for the next 70 years the Boötids all but disappeared, with two to five dim meteors an hour during the peak. Then, in 1998 — and I remember it still — the sky came alive over a seven-hour span, with upward of 100 meteors an hour including some blazing fireballs blazing across the night sky.
    The Boötids are the offspring of comet Pons-Winnecke, which circles the sun every six and a half years. At its farthest it crosses Jupiter’s orbit, while at its closest to the sun it is closer than earth’s orbit. Comets are made up of bits of debris left over from the formation of the solar system all frozen together like a dirty ice ball. With each approach to the sun, some of that ice melts, setting loose bits and chunks of rock that trail the comet in its orbit around the sun. As earth passes through this trail,  debris ignites when it strikes our atmosphere, creating the meteors we commonly call shooting stars.
    The Boötids appear to emanate from the constellation Boötes the herdsman, but with luck we’ll see them anywhere in the northern sky.
    Look for the nascent crescent moon with Jupiter to its lower right low in the west immediately after sunset Sunday. Monday evening, the moon shines higher above and farther to the west of sinking Jupiter, which disappears from sight within the next couple weeks. By Tuesday the moon appears higher and farther east at sunset, just a few degrees from Regulus, the ultramarine heart of Leo the lion.