Karen Vettorel, age 9, of Tucson, Ariz., for her question:

On a clear night, the stars light up the sky like tiny lanterns. But the sky is big, far bigger than you can imagine. Our world is a globe like a giant bail. The sky stretches around it, out in all directions. It stretches on and on, farther than your mind can reach. Out there in the vast ocean of sky, a million miles is no distance at all. Most of the stars we see are many billions of miles apart.

Faraway things tend to look smaller. The mountains seem to shrink as we drive away from them. The nearest star to us is our golden suns and it is more than 92 million miles away. The brightest star in our night sky is almost fifty million, million miles away. Our sun looks so big because it is so much nearer than the rest of the stars.

Of course, we do not look directly at the sun on a clear day. For it is powerful enough to harm our eyes, But we can sometimes see it dimly on a cloudy day. It looks no bigger than the moon. And, we are told, the moon is only about a quarter as big as the earth. Is the earth four times bigger than both the sun and the moon?

Not at all. Remember that faraway things tend to look smaller. The sun is about 400 times wider than the moon and it is also about 400 times farther away. This is why they look to be more or less the same size. Actually, the sun is big enough to gobble up a million worlds like ours. It would still have room to gobble up a million moons for dessert.

Some of the stars look big and bright and some look pale and dim. But our sun seems to be much bigger and brighter than any of them. This is only because the sun is so much nearer to us than the faraway stars. Our sun is just a middle‑sized star. There are many stars which are much bigger and there are a few stars which are no bigger than our world.

Some of the pale looking s tars are really big and far away. Some of the bright stars are smaller and nearer to us. The brightest stars are those which are big and not too far away.

Let's pick out some stars on a clear winter night. The brightest group, shaped like a long diamond, 3s called Orion. Find the row of three stars in Orion’s belt. Go way up to the top of the diamond and find a big dull red star. This is Betelguese, big enough to swallow our sun a million times, Now go way down to the bottom of the diamond. This star is Rigel, almost two thousand million miles wide. These whopping stars are both big and far away. If we wanted to write the distance of giant Rigel in ordinary miles, we would put 4, followed by 15 zeros.

To the west of Orion is Sirius, the Dog Star, brilliant as a diamond. Sirius is several times bigger than our sun. But it is about 50 million, million miles farther away. And the Dog Star has a companion, called the Pup. This little white star is too small for our eyes to see from so far away, It is not much bigger than our world. Most of the stars are about the same size as our sun. But others are whopping giants and some are tiny dwarfs. They are scattered, some near, some far, across the vast oceans of the sky,