Mars is low in the southwest as night falls. It looks like a fairly bright orange star. And if you have strong binoculars or a telescope, you might make out a fuzzy companion quite close to the planet the next few evenings. Comet Siding Spring will be just to the left of Mars tonight, and closer to the right of Mars tomorrow night. The comet could create a brief but intense meteor shower on Mars tomorrow, as a barrage of dust grains slams into the planet’s upper atmosphere. Debris from a different comet will strafe Earth over the next few nights, spawning our own meteor shower. It’s not a great one, but there’s not much moonlight around to interfere with the fireworks, so it’s worth a look. The Orionid shower is created by Comet Halley. The comet hasn’t visited the inner solar system in a quarter of a century. But as it orbits the Sun, it sheds small bits of rocky debris. These grains of dust spread out along Halley’s orbital path. Earth flies through this path every October, so some o
