(c) Anthony K. Grafton 2003

Falling Stardust

In just a few weeks, you can observe small bits of ancient stars burning up in the Earth’s atmosphere. Commonly known as falling stars, you can observe the meteor shower known as the Lyrids From April 23^rd through April 25^th.

The Lyrids are, like most meteor showers, associated with a comet, in this case the comet Thatcher. Comets are clumps of ice, dust, and rock that have long, highly elliptical orbits around the sun. As they orbit, they leave behind trails of dust. Sometimes the Earth passes through one of these dust trails producing regular meteor showers. Because the orbit of the Earth and the orbits of many comets are known very accurately, the arrival time of meteor showers can be predicted many years in advance.

Comets and asteroids, the scientific name for small chunks of rock orbiting the sun, are mostly leftover relics from the formation of our solar system. Around 5 billion (that’s 5 followed by nine zeroes) years ago, a huge dust cloud leftover from the explosion of ancient stars collapsed due to gravity to form our sun. The dust, gas, and rock not absorbed by the sun eventually congregated together to form planets, and the remaining bits and pieces of this cosmic soup formed asteroids and comets.

Even though the moon will be rather bright, take some time to look up late at night April 23^rd, 24^th, and 25^th. The Lyrids will seem to emanate from the constellation Lyra, right above the constellation Cygnus (the Northern Cross). Record the time of each meteor you observe and e-mail your data to Science Corner, and a future column may include your results. Remember, each meteor you see is a bit of dust billions of years old reaching a dramatic end in our atmosphere.