Perseid Meteor Shower 2015

As you read this Thursday (Aug. 13, 2015) you will be saddened to learn that last night, between 11:00 PM and 4:00 AM this morning was the optimal viewing time for this year’s iteration of the Perseid meteor shower.  And this is supposed to be a banner year as the event is occurring during a new moon (not visible).  I guess that will teach you to rely on me for all things scientific.  But don’t despair; you should be able to experience a relatively satisfying observation tonight during the same time window.

Comet Swift-Tuttle

“So what causes a meteor shower?” you ask.  Well, as we perceive it, it seems like dozens, or hundreds depending on conditions, of little lights are falling from the sky.  In reality, the Earth, in its normal orbital trip around the Sun, is barging through a debris field of very small remnants of material blown off of a comet as it made its way around on its own orbital path.  In the case of the Perseid shower, the debris is from the comet Swift-Tuttle.  Swift-Tuttle was discovered independently by Lewis Swift and Horace Tuttle in 1862.  It was last close enough to Earth to be visible in 1992 (I saw it.  Did you?).  As the comet nears the Sun (one orbit takes 133 years) the solar wind heats the ice enough that some of it melts and is left as a trail in the orbital path.

Every year, in its normal orbit around the Sun, the Earth crosses the Swift-Tuttle’s debris trail and the collisions between the Earth’s atmosphere and the tiny little pieces of ice (and perhaps some minerals) light up as “shooting stars” as they burn up in our atmosphere.  It is really the Earth’s trespass into the comet’s debris field that causes the light show.  This happens independent of where the comet is in its orbit.

Although the peak viewing window was last night, you will still have an opportunity to witness a fairly good show, weather conditions allowing, Thursday night/Friday morning. While you can see the meteors in any quadrant of the sky, the direction from which most will emanate is north.  The shower is named “Perseid” as it is the Perseus constellation from which they seem to be radiating.  But remember, we are running into them.  You needn’t focus solely on the radiant (apparent source) as the distribution of occurrences will be somewhat random across the sky.  The only danger is if you get dizzy form looking up and fall down.

The highest concentration of meteors will once again be between midnight and 4:00 AM.  If you have trouble finding these “shooting stars”, feel free to not call me.  I am unplugging my phone when I go to bed.

PS  The weather did not cooperate overnight, thus I saw no shooting stars... alas.  Hope you have better luck tonight.