After two months in orbit 300 miles above the earth, an automatic telescope designed and assembled at the Harvard College Observatory is working perfectly. The ultra-violet light experiment aboard Orbiting Solar Observatory VI (OSO-VI) "is meeting 100 per cent of our expectations," said William H. Parkinson, lecturer on Astronomy and co-director of the project. "We've got a winner."

The 640-pound satellite was launched from Cape Kennedy on August 9. Besides the Harvard telescope, it contains 6 other experiments designed to measure solar emissions such as x-rays, ultraviolet light and neutrons that are ordinarily blocked from view by the upper layers of the earth's atmosphere. When ever the satellite emerges from the earth's shadow, two of these devices, including Harvard's telescope, constantly scan different portions of the sun's disc and record the intensity of the sun's radiation in varying sections of the spectrum.

Leo Goldberg, Director of the Harvard College Observatory, proposed the telescope project some 10 years ago. Since 1961, Parkinson and Edmond M. Reeves, lecturer on Astronomy, have been the project's co-directors.

NASA has so far provided $30 million to build the Harvard ultra-violet experiment and to process the results.

Ultra-violet measurements, like these, are important because ultra-violet rays from the sun occasionally interfere with earth's radio communications, and the energy from these invisible light waves supplies much of the solar heat that determines the earth's weather. Astronomers use slight, variations in the sun's ultra-violet spectrum as clues to the chemical and physical reactions goingon at various depths in the sun. By comparing satellite measurements of invisible radiation with earth-bound records of the sun's visible light, scientists should be able to predict some of these reactions and their effects on earth's weather and communications. Space travelers also need accurate forecasts to warn them of outburst of dangerous radiation.

The astronomers have aimed their telescope at several features on the sun, including "active regions"-the eruptions of hot material that appear against the "cooler" regions of the sun's surface. Active regions increase and decrease over an 11-year cycle. "This year is supposed to be a solar maximum-a period of maximum solar activity-but in spite of that, the sun has been notoriously quiet," Reeves said. "But this week the sun has perked up again."

"We haven't discovered any outstanding new phenomena," Reeves added, "but a great many observations that had been qualitative are now quantitative. Now you can start calculating the sun's behavior."

Besides observing the sun, the OSO-VI telescope has measured the absorption of ultraviolet light by the earth's upper atmosphere an important factor in the earth's weather.

The Harvard experiment is contained in a 40-inch box that is open at one end. The box is plated with gold to distribute heat evenly. A cluster of 13 light detectors-much like the electric eye on a camera-keeps the box pointed at the sun. A small telescope mirror collects solar rays coming through the open end of the box and then reflects them onto a diffraction grating, a row of closely-scaped lines that breaks the light up into a spectrum. This spectrum constantly changes as different chemical reactions occur on the sun.

The visible light region of this spectrum would show up as color bands, but the invisible ultra-violet rays can be detected only by a special electric tube. In the experiment, this tube acts like a television camera, converting the ultra-violet rays to electric impulses that are transmitted to earth.

A small motor moves the diffraction grating to examine any one of 10,000 different wavelengths or areas of the spectrum. A second motor keeps the telescope aimed at a single point, or else it shifts the entire telescope back and forth to scan small areas of the sun. It thus obtains a television picture in a particular type of ultra-violet light.

No one knows exactly how long OSO-VI and its Harvard experiment will continue to operate. OSO satellites are designed to last six months, but one earlier OSO has been working for nearly two years.

Since Goldberg first proposed the OSO telescope, the project here, like most satellite experiments, has run into major technical problems.

In 1965 and 1967, OSO satellites carried Harvard telescopes similar to this one. But the first telescope aboard OSO-II failed only seconds after being switched on, and a surge of electric power from a faulty transformer ruined the telescope on OSO-IV after six weeks of operation. However, the data from those six weeks has kept astronomers here more than busy for two years.

So far the best explanation for the OSO-IV failure is that a small bubble of gas was trapped in a plastic coating that surrounds the transformer's wire coils. As the gas slowly leaked out it caused a surge of electric current that burnt out the experiment's electric system.