Perseids

From South Dublin Astronomical Society

Each year in the astronomical calendar there are a few celestial events that spark great interest among those who enjoy astronomy. One such event is probably the most dedicated meteor shower for the last 3 centuries, The Perseids Meteor Shower. It is just like any other meteor shower, only this one has more significance to it.

That significance is the abundance of falling stars at its peak, without failure to show up, and always unleashing a few surprises. Surprises like fireballs – extraordinarily large meteors that will break up as they burn, with the lucky few making an audible sonic boom as it streaks through the atmosphere. And bursts of many seen within minutes, and sometimes seconds, of each other.

Most meteor showers comefrom debris ejected from comets. With the Perseids, it was the passing of a comet called Swift-Tuttle, so-called because it was discovered by 2 independent observers at the same time: Lewis Swift of New York, and Horace Parnell Tuttle of Massachusetts, in July 1862.

Swift-Tuttle has a period of 135 years. It last passed close to Earth in 1992, leaving behind a fresh dust tail. Thus, each year, we pass through this dust tail, and previous dust tails left behind by Swift-Tuttle, between July 20 to August 22. But the fireworks take place on August 12/13 each year, as this is when we pass through the densest part of the tail stream. What we see is a rise in shooting stars across the sky, particularly in the northeast. All you need is to wrap up warm and keep your eyes peeled. In 2006 a bright Moon hinders all but the brighter meteors unfortunately.

Sources

Original Article by Seanie Morris, Tullamore Astronomical Society