Bobbie Van Kirk, Age 11, of Lowell. Ore., for their question:
What causes falling stars?
A medium size star could swallow our world a million times and still have room for dessert. So those bright sparks that arch across the night sky cannot really be stars falling to the earth. True, they look as big and they shine as bright as the distant stars. But most of them are not bigger than grains of sand.
The sun and its planets are huge bodies, but most of the solar system is empty space. Let's imagine a small model with a sun as big as a two foot beach ball. On this shrunken scale, the rim of the solar system would be almost three Miles wide. The earth would be as big as a pea and giant Jupiter would be the size of an orange.
The orbiting planets are separated by millions and millions of miles. And through these oceans of space sail countless smaller bodies ranging in Size from specks of dust to giant boulders. For untold ages these space travelers have been zoning through the solar system at speeds up to but not exceeding 26 miles a second.
They are called meteors, and we do not eee them unless they happen to have a traffic accident with the earth. Then down they swoop into the atmosphere, which acts like a brake and forces them to slow down. This causes friction, and friction causes heat enough heat to set the falling meteors on fire. Then we see them arching down as so called shooting stars.
A swarm of meteors may be the dusty debris frcm a passing coaaet. Other meteors may be fragments left over when the planets were formed. Most meteors burn to ashes in the air, but a few large ones survive the fall and land with a crash. They are Meteorites. Some meteorites are made of stony minerals like the earth’s crust and some of metals like those in the earth's core. It is possible that these meteorites are the fragments of a tenth planet which once broke apart into small bits but we are not sure.
A meteor travels the cold spaceways for countless ages. Its Journey ends when lt comes c1ose enough to feel the gravity of the earth. Then it is pulled down, through the air which makes it burn. For a second or so a falling Meteor may look bright as a star though it is most likely no bigger than a grain of sand.