Donald H. Menzel, director of the College Observatory, and Fred L. Whipple, professor of Astronomy, agreed yesterday that prospects for interplanetary travel are based on "fact rather than fiction," but they saw many obstacles in the way of journeys into space.

Both scientists agreed that several problems of interplanetary travel, such as sufficient speed, power and temperature control necessary for reaching even the moon, were beyond the scope of present scientific knowledge.

"But some of us will live long enough to see men reach other planets," Whipple predicted at a Ford Hall Forum discussion last night.

Whipple, who is a consultant for the Armed Forces and a member of the International Geophysical Year's central committee, praised the Defense Department's plan to launch six "earth satellites" for the Geophysical Year as a major step in the exploration of space.

The "satellites" will be fired to a height of 200 to 800 miles, Whipple stated, for observation of gravitational effects at this altitude. The missiles, he added, are "unprepossessing in appearance" since they only consist of 30-inch spheres and weight 21 pounds.

They will be shot by rockets with a 27,000 pound thrust to circulate at a speed of five miles per second for an indefinite duration, he explained.

Eventually, experiments will permit rockets and even human beings to land on other planets, Whipple concluded.

Menzel, the other speaker at the Forum, doubted whether life can exist on other planets because of extreme climatic conditions.

It is unlikely that living creatures exist on other planets or that the earth is being explored by "flying saucers," he stated. He attributed the sighting of "saucer-like objects" to atmospheric distortions of stars or of ice crystals.