This Week’s Night Sky: A Lion Makes a Meteoric Roar
Dozens of shooting stars from the annual Leonid meteor shower will streak across the sky mid-week.
Easily mistaken for lights from distant cities or even the faint radiance of the Milky Way, the pyramid-shaped glow above the eastern horizon is caused by sunlight reflecting off dust particles spread out between the planets in our solar system.
Like most meteor showers, the Leonids are caused by Earth plowing through the dust trail left by a comet. The Leonids come from the trail of the 1.2-mile- (2-kilometer-) wide comet Tempel-Tuttle, which circles the sun every 33 years. When the comet gets close to the sun, melting ice releases pieces of dust—most no larger than a grain of sand—and deposits them in clouds that Earth encounters every year around mid-November.
Even the fainter meteors may be seen after the waxing crescent