Mrs. Savitskaya in space

Astronauts are ''envoys of mankind'' in the fine phrase of the world's outer space treaty of 1967. Obviously such envoys cannot be representative of Earth's humanity without women among them. As the Soviet Union's Svetlana Savitskaya sets a new endurance record for women in space, and America's designated first woman astronaut looks forward to her assignment, the time is coming when nothing has to be made of an astronaut's gender.

It took almost 20 years for Moscow to launch a second woman cosmonaut after Valentina Tereshkova's flight of almost 71 hours in 1963. Miss Tereshkova went on to become one of the few women on the Communist Party's Central Committee.

What will Mrs. Savitskaya do for an encore? The daughter of a World War II air ace, she had already broken three world parachute jump records by the time she was 17. She became a world champion of aerobatics. Now she is helping science understand such matters as the effects of prolonged weightlessness.

Her male colleagues were hardly up to date in offering ''Sveta'' a ''lady of the house'' apron. But she was up to date in wanting the work rules specified before she tried it on. Obviously she'll go far.