Shooting Stars

There are many little chunks of rock present in space. Their sizes range typically from the size of a grain of dust to the size of a golf ball (the latter being more impressive in the night sky, but also more rare). As the Earth moves around the Sun, it will run ito some of these small rocks that collide with the atmosphere at great velocities. Going through the atmosphere they begin to heat up, start to glow, and then burn down. This is what we see when we look at a shooting star (which we call a meteor). There are millions of such particles colliding with the atmosphere every day (I mean day and night). But since you can only see them at night, and you can only look at a small part of the sky at once, when stargazing you can expect to see a shooting star every 10 to 15 minutes. This is on a regular night. When we get meteor showers, we get many more. A meteor shower happens when the Earth goes through a region of space that is especially filled with dust and chunks of rock. Therefore we get many more meteors at these times. More precisely, meteor showers happen when Earth, on its way around the Sun, passes through the path of a comet. That's because as a comet orbits near the Sun, it starts to melt down and ejects on its path lots of dust and chunks of rock. The yearly meteor showers are caused by this. In any given night, you can also see more shooting stars (in fact about twice as many) just before dawn. That's because at dawn we are facing the direction in which the Earth is moving, so we intercept more of the stuff in space.