Astro Bob: Rise early on Oct. 22 to see meteors from Halley's Comet

Every October, Earth crosses the orbit of Halley's Comet, and we're pelted with its dusty debris. Sand-grain-sized bits of rock boiled off the comet during its repeated passages of the sun spread out along its orbit like a contrail behind a jet plane. Traveling at 18 1/2 miles a second, Earth slams into the material, and it strikes our atmosphere at around 148,000 miles per hour. Earth orbits through debris littered by Halley's Comet every October. As we pass through the stream, bits of the comet incinerate in our atmosphere and flare as meteors. The yellow arrows show the direction of the stream. The blue arrow shows the direction of Earth's movement around the sun. See a live, interactive version of this at meteorshowers.org. Contributed / Ian Webster, Peter Jenniskens, with additions by Bob King Even a sand grain possesses a hefty amount of energy at that speed. It compresses and heats the air in its path, which strips away its atoms and transforms the air around it in