October is a good month for seeing a meteor, or three. Throughout the year there are many ‘major’ meteor showers (and numerous ‘minor’ showers), those quick streaks of light sometimes called ‘shooting stars.’ What, exactly, are they? Debris…. They are sometimes left-over bits from the formation of the Solar System, most times it is material cast off of a comet. Either way it got in the way of the planet Earth. The Earth as it orbits the Sun clears its orbit of ‘debris’, and in doing so the small particles are caught in the gravity of Earth and burn up in the atmosphere. Most, also, never make it to the ground. It takes a sizable piece of material to pass through the atmosphere, to survive the intense heat and pressure, to impact the ground. Typically, meteors start their blaze of glory in our night sky as the size of a grain of rice.
In October, the Orionids peak on the weekend of October 21st. Meteor showers are named after the point in the sky that they originate from. Drawing lines on a star chart for meteors seen in a night, or several nights, will, should, show they mostly came from the same point or area in the sky. I say ‘should’ because there are ‘minor’ meteor showers happening, members from another known radiant, and then there are the pesky sporadic, random, debris pieces that are seen blazing across the sky that are nowhere near any (known) radiant. The Orionids radiant is in the constellation Orion, The Hunter, a very prominent constellation many see as a bow tie in the winter sky. So, what actually laid down the material around the Sun that show up in our night sky we call Orionid meteors? None other than, the famous – Comet Halley. It will be some number of years before we see that comet again (2061), but every year we see its dynamic effect on the Solar System when Earth sweeps up the material that was once the comet tail, debris cast off by Halley’s Comet.
Last month I mentioned to find Cassiopeia, a ‘W’ shaped constellation low in the northeastern sky. Take the time to find it now! It is on-end, a ‘W’ or ‘M’ depending on which way you tilt your head. Next month it will be well placed in the night sky for a binocular tour. Filled with star clusters and nebulae the area from Cassiopeia the Queen to Perseus the hero, both of Greek mythology, is a rewarding place to point any optical device.
Steven Aggas owns Apache-Sitgreaves Observatory, the largest public viewing telescope in Arizona in Overgaard, AZ. Visit apache-sitgreaves.org for tickets.