David Ii. Davis, age 10, of Phoenix, Arizona, for his question:

How much closer is the sun in the summer?

In July, the distance between the earth and the sun is about 94,500,000 miles. In December the distance is about 91,403,000 miles, which is a little more than three million miles closer. You would expect thins to be warmer in December because then the are closer to the sun and should get more of its warmth. This is strange. But south of the equator things get stranger. People down there enjoy their summer season in December, when the earth really is closer to the sun. It seems that a few million miles does not make much difference to the amount of warmth we get from the sun. Actually, the warm and cool seasons occur because the earth's axis is tilted. In July the Northern Hemisphere bows toward the sun and we get longer hours of direct sunlight. True, the sun is farther away, but it climbs higher in the sky and the days are longer. This is what really brings our summer season.