August is meteor shower month, with the most-watched display of the year lighting up our night skies during the balmy evenings of late summer. Last year, the show was partially obscured by bright moonlight, but this year that will not be a problem (unless the wildfire smoke remains an issue).
The meteors will be flying from mid-July until later August, but the best nights will be after midnight until just before dawn on Aug. 11-13. Why so late at night? If you look up into the eastern sky at midnight, you are actually facing the direction that the earth is moving in its orbit around the sun. It is kind of like driving through a snowstorm. More snowflakes hit the front windshield of your car than the rear.
Usually when we talk about astronomy, huge numbers and vast distances boggle our minds. Meteors are something we can wrap our heads around. The average “shooting star” (what a misnomer!) is only about the size of a grain of grape nuts cereal. Stars are huge, dwarfing our little planet in size. Meteors are not very far away either, only about 60 to a 100 miles above our heads.
The meteors will mostly be coming from a point in the sky near the constellation Perseus, where they get their name, the Perseids. They can be seen anywhere, but trace their trails backward and they will all lead to the northeast. There will be other meteors out there not associated with this shower, but their trails will go off in other directions. As the night progresses to dawn, that point of origin will climb higher into the sky as the earth turns towards the east.
In case you are wondering where the meteors are coming from, think about comets. As they come in close to our sun, they shed some of themselves as debris in the inner solar system. Think of a skyrocket shooting off sparks as it flies up into the sky. Comet Swift Tuttle makes one orbit around the sun every 130 years, leaving behind a wake of dirt. Every year in August, we plow through that dirt it cast off in previous passes around the sun. When that debris hits our atmosphere, friction with the air causes it to heat up and burn.
At the end of the second week in August, step outside in the early evening. A slim crescent moon will be hanging in the west in the twilight glow with the brilliant planet Venus nearby. Then take out a lounge chair, some mosquito repellant and a blanket to stay warm. That is really the only equipment you will need for a night of meteor watching. That crescent moon will set before the show gets good at midnight. Do not forget to turn off your porch light. The meteors will have a hard time competing with it. The darker the better.
If at first you do not see much, do not lose patience and give up. Meteor showers often come in spurts, with lulls in between where nothing is happening. If you are lucky you might witness a meteor storm when so many are shooting across the sky that it is hard to keep up with them.
Maybe you will even see an “earth grazer” flying across the sky from horizon to horizon. These usually happen closer to midnight when that point of origin is close to the horizon. Try to stay up until you see at least one fireball for which this shower is famous. They can be quite spectacular.
When you are out there and if it is a clear night, be sure to take in the Milky Way, that band of light stretching from north to south across the sky. That is our home galaxy where we reside in the vast cosmos with hundreds of billions of stars.
Hopefully, the smoke will not spoil the show.