Is there anything more peaceful than lying on your back on a warm summer night, gazing at the stars and watching a meteor fly by?
You’ll be able to see this phenomenon for yourself this summer during the Perseid meteor shower on the nights of August 12-13.
The Perseid meteor shower is one of the most popular because it occurs during the warm month of August, when people spend more time outdoors enjoying the weather.
It is also well known because it shows many meteors. On rare occasions, an observer in dark skies (such as within our provincial parks) can see up to 120 or more meteors per hour, i.e.‘s Two per minute!
Most observers typically see about 60 meteors per hour in moonless skies. Unfortunately, this year the waning gibbous moon will light up the skies just as the meteor shower begins.
What is a meteorite?
Meteors are small grains of dust that, on average, are no larger than the size of your thumbnail. They are actually remains of comets.
As these “dirty snowballs” orbit the sun, they melt much of the meteor off its surface, leaving dust grains behind.
The comet’s nucleus may be small, but the trail of material (tail) extending behind it can last tens or even hundreds of millions of kilometers.
Once the comet passes the Sun, the debris can still orbit for quite some time. If the Earth passes through this material, the pieces of dust burn up in our atmosphere causing heat which, in turn, causes nearby gas molecules to glow.
Surprisingly, astronomers believe that up to one hundred million tons of meteorite material could fall to Earth each year.
Most of it is small dust that probably gets trapped in our eaves, and we don’t even notice!
Where do meteors come from?
Meteor showers are named after the constellation from which they appear to originate. Of course, there is no connection between the constellation and the meteor shower, however, an optical illusion provides us with that perspective.
If you drove a car at night toward a swarm of mosquitoes, the headlights reflected by the mosquitoes would appear to come from a point directly ahead.
The truth is that mosquitoes are everywhere. However, due to the speed and direction of travel of the car, it appears that the mosquitoes originated from a single point (the radiant).
In a meteor shower, the movement of the Earth is similar to that of a car and the material of the meteorite is similar to that of mosquitoes.
The Perseid shower is so called because the rays of light appear to recede to a point between Perseus and Cassiopeia.
Tips for observing meteorites
Here are some tips on how to make the most of your meteor shower experience.
- Bring a blanket or something to sit on and an extra layer of clothing for the cooler nighttime temperatures.
- The best time to observe meteors is when the sky is darkest. Moon phases make a difference (the less moon, the better)
- Shooting stars (meteorites) are fairly easy to spot if the sky is clear and you have a sharp pair of eyes.
- Be patient. Meteors tend to appear in waves with lulls in between.
Want to know more about what’s happening in the night sky this month? Check out the August issue of Eyes on the Skies.