Among the night's visible stars and planets is a little-known, manned Soviet space station, which will travel across the Washington sky tonight.

William E. Howard III, technical director for the Naval Space Command in Dahlgren, Va., who has plotted the course of the space station, said that from this area the station, which will pass about 200 miles above Earth, is visible to the naked eye.

Since determining the position of Mir (pronounced MEER), which the Soviets launched for scientific research on Feb. 20, 1986, Howard has seen at least 10 evening passes of the space station in the past year.

To find Mir, evening sky gazers must know the precise time and location, because its passage over this area lasts no longer than five minutes. Tonight's passage begins about 9:50 p.m. in the north-northwest sky, just above the horizon. Mir is expected to rise to the middle of the northeastern sky by 9:52 p.m. and by 9:55 journeys east as it nears the horizon.

However, tonight and Saturday night Mir will move into the Earth's shadow before it reaches its apex in the sky, making it nearly impossible to see.

The next best passage takes place Monday night, when Mir rises from the northwest and moves almost directly overhead at 86 degrees, crossing the northeastern sky.

The space station will be sporadically visible to area residents as long as the Soviets keep it aloft.

Mir reflects the sun, making its travels over Washington conspicuous. In astronomical terms, Howard describes the brightness as "either zero or one magnitude." That makes it as bright as Saturn, which has been a brilliant night object throughout the summer.

To the casual sky gazer, Mir's passing resembles an airplane, Howard said. "It goes a little faster than an airplane, except there are no blinking red or green lights."

Howard suggests using a pair of low-powered binoculars or just the naked eyes to view Mir. Binoculars, he said, could differentiate Mir from the flight of an airplane.

The Soviets devoted Mir, which means "peace" in Russian, to scientific research, said Marcia Smith, a specialist in aerospace policy at the Library of Congress. The third-generation space station, which could fit into the cargo bay of a U.S. space shuttle, is the Soviets' seventh successful one. The United States has launched only one, Skylab, in 1973, to which three crews were sent.

Mir hosts a two-man crew: Col. Yuri Romanenko and Alexander Aleksandrov. Romanenko has been cooped inside since February; Aleksandrov climbed aboard in July, replacing Alexander Laveikin, who left the station for health reasons.

The location of Mir is public information. "They {the Soviets} know where it is, much like we do," Howard said. "Anybody can go out and see it."