Russia's second earth satellite, launched into its celestial orbit Saturday will not be visible in the United States until early December.

Fred L. Whipple, director of the Smithsonian Astrophysical Observatory here, said yesterday that a preliminary study of the rocket's orbit has shown that until that time it will not pass over this country during the hours of morning or evening twilight, the only times it can be sighted.

The Smithsonian will therefore pay little attention to the second satellite until December, when its "Moonwatch" visual spotting stations can begin submitting visual information. Whipple says that he also expects the first satellite's rocket to fall into the earth's atmosphere at about that time.

United States tracking operations for the second "moon" will meanwhile be based on information from radio contacts, primarily those made by the Naval Research Laboratory's minitrack stations.

Many scientists still believe that the Soviets are planning the announcement of some further scientific achievement for Nov. 7, the 40th anniversary of the Russian Revolution. Whipple estimated that "if the Russians want to land something on the moon Nov. 7, they would have had to shoot about five days before --about Nov. 2."

He said that to propel a missile to the moon would require about 40 per cent more power than went into either of the satellites previously launched. An atomic bomb explosion, he suggested, would be the best way to signal a missile's hit on the moon.