Nancy Parker, age 15, of Waxhaw, North Carolina, for her question

Whv do Saturn's rinses sometimes disa»near?

We cannot see the rings of Saturn at all without the help of a telescope. This is a pity because they are one of the most dazzling sights in our Solar System. Even a small telescope shows them as sparkling, golden circles around the big golden planet. That is, if we happen to train our telescope on Saturn at the right time. We never see the rings as a flat, open circle with the separate planet in the center.

At best, they appear as a golden oval with its far sides hidden by bulky Saturn. Gradually the ovals become narrower and thinner. A few years later you cannot see them through a small telescope.

As we circle the sun, the earth and Saturn change their positions in relation  to each other. As our view of the big planet changes, we see its circles from  different angles. The golden ring system is about 165,000 miles from side to side  and it reaches to immense heights above Saturn's equator. But the system is just a  few miles wide. As Saturn's equator tips toward and then away from us, so do the  rings. In 1958, Saturn was tipped to show the golden ovals at their best. This  happens twice in about 30 years. Later the system tips to show us a thin, edge on  view. The faraway circles are then too far away to be seen through a small tele¬  scope and for a while the rings of Saturn seem to disappear. FOR FURTHER INFORMATION GO TO: NASAJPL IN THE SCIENCE NEWS MENU.