Clay Sheff, age 10, of Tahlequah, Oklahoma, for his question:

Why don't our rockets burn up like meteors?

Actually, a returning space rocket and a falling meteor face the same problem. They must travel at great speeds through the earth's atmosphere. There are gaseous molecules, even in the thin air hundreds of miles above the surface. A speeding object creates friction as it bashes through these rare gases    and friction generates heat. Most meteors get hot enough to catch fire and burn to ashes before they reach the ground.

This was a Big Problem during the early days of the Space Age. As the first rockets fell, they caught fire like meteors. However, long ago mankind had invented fire resistant bricks to line furnaces. These ceramics can withstand 3000 degrees Fahrenheit. So ceramac materials were developed to shield our falling rockets. These heat shields have been improved to protect returning spacecraft. During the fall, a heat shield gets as hot as a meteor    but it keeps most of the heat from getting inside.