Orionid Meteor Shower in October

Planetarium with starsBob Hayward –

Astronomers at the Pisgah Astronomical Research Institute (PARI) remind the public of the annual Orionid Meteor Shower in October.

Meteors result from particles of dust causing the atmosphere to glow as the particles enter the upper atmosphere of the Earth. The Orionid (pronounced Or-e-ah-nid) meteors, or “Orionids,” are associated with Comet Halley.

This comet, undoubtedly the most famous comet of them all, has been observed at least since 240 BC. But it wasn’t until 1705 that Edmund Halley realized that a number of bright comets that had appeared every 76 years throughout history were actually a single comet returning periodically as it orbits the Sun.

As Halley’s Comet revolves around the Sun, it gives off gases and dust particles due to the heat of the Sun. While the gases eventually disperse throughout space, the dust particles remain as a trail of debris in the path of the comet. Since the Earth encounters this trail of debris at the same point in space each time it makes its annual revolution around the Sun, we observe the Orionids on the same date each year, around October 21.

As with all meteor showers, the Orionids are best observed between midnight and dawn from a dark location with clear skies. In 2015 the Orionids are predicted to reach a peak of about twenty meteors per hour about 7 p.m. EDT, Wednesday, October 21, 2015.

This shower generally lasts for about two days; so one should expect to see Orionids the mornings of the 21st and the 22nd. We will have a waxing gibbous moon those nights so it will be setting shortly after midnight. Thus, in the predawn hours, there will be no moonlight to interfere with observing the fainter meteors.

Look high in the east to find the meteors appearing to radiate out the area at the tip of the club of the constellation of Orion the hunter, near the feet of Gemini the twins. Binoculars or telescopes are not needed to observe meteors.

About PARI

PARI is a public not-for-profit public foundation established in 1998. Located in the Pisgah National Forest southwest of Asheville, NC, PARI offers STEM educational programs at all levels, from K-12 through post-graduate research. For more information about PARI and its programs, visit www.pari.edu.