PREPARING FOR FLIGHT: The Princeton Space Telescope is lowered by NASA technicians to its berth on an Atlas/Centaur rocket. It was launched on August 21.
Princeton Alumni Weekly. October 10, 1972.
The often-troubled Princeton OAO experiment finally takes off!

The successful launching this summer of the Orbiting Astronomical Observatory, developed at Princeton, brings to fruiting an experiment that has been threatened in the past by technical failures and budgetary cutbacks. The 4,900-lb. satellite, equipped with a telescope powerful enough to pick up a basketball from 400 miles in space, will train its eye on the places where the universe is being created and destroyed and will seek to discover the building-block elements of the cosmos itself. Florence Helitzer, our author, is assistant director of public information, specializing in subjects of scientific interest. – Editor (1972).

On Monday, August 21, an American spacecraft bearing the Polish astronomer’s name, Copernicus, was successfully launched by NASA from Cape Kennedy. The cargo aboard Copernicus was a 32-inch, ultraviolet telescope, the largest and most expensive ever lofted into space. Each of six Princeton astronomers had spent between two and 12 years living with this machine (henceforth to be called the Princeton Space Telescope). The system, after a necessary waiting period for air and other gases to escape from the instrument, was to be turned on the following weekend. In the interim, the breathless silence in Peyton Hall, home of the university’s Astrophysical Sciences Department, was like the void of space itself. Copernicus was the fourth and final spacecraft in NASA’s Orbiting Astronomical Observatory Series. The two previous Princeton OAO’s had failed. (One, launched in December of 1968, carrying instruments provided by the University of Wisconsin and the Smithsonian Institution’s Astrophysical Observatory, is still functioning.) But by Saturday, August 26, the first stellar signals received by the telescope 425 miles in space were transmitting to the Goddard Flight Center in Greenbelt, Md. By the following Monday, it was evident that all systems were functioning exactly as planned.


Not surprisingly, Lyman Spitzer Jr., Charles A. Young Professor of Astronomy and Chairman of the Department of Astrophysical Sciences, the man with whom the Princeton Space Telescope project originated, is a mountain climber. This particular climb started in 1946 when American scientists first began to investigate the German V-2 rockets. Spitzer immediately foresaw the eventual possibility of a telescope in space. Few people agreed with him.

On August 26, when the telescope first picked up light from a star, Spitzer had finally achieved the pinnacle. From this height, he and other astronomers elsewhere would have a view of the universe, impossible to achieve from ground level because the earth’s atmosphere screens out most ultraviolet rays. The study of the absorption of ultra-violet starlight will provide scientists with a new and very powerful tool for probing the composition and state of matter in space and for learning what the universe is made of.

It had been a long ascent. On June 17, 1954, Richard T. Baker, reporting for the New York Times, wrote:

Lyman Spitzer, Jr. predicted “a platform in space from which to make recordings of celestial activities.” Dr. Spitzer termed it “a logical next step” in the development of space astronomy. “An observatory above the earth’s atmosphere” he said, “would increase man’s understanding of the universe by permitting him to see five to ten times as far and with finer precision. At present,” he explained, “eyeing the universe by looking up from the bottom of the earth’s atmosphere was like trying to see something from the bottom of a tank of turbulent water. The atmosphere screened out many of the rays the revealed celestial information and distorted all of them.

“The satellite device” predicted by Dr. Spitzer “might be completely unmanned and made up of a complex of instruments automatically transmitting their records by shortwave to the earth.”

In 1960 NASA undertook sponsorship of OAO-C (Orbiting Astronomical Observatory-C), as the project has been called. Actually Spitzer had been seeking financial support for the program since 1946. It was the successful Soviet Sputnik of 1957 which created the climate for American space exploration and for the basic research to support it. In 1960, Lyman Spitzer was director of the once-classified Project Matterhorn (named by him after the spectacular peak), which has evolved into Princeton’s Plasma Physics Laboratory; a facility where scientists are intensely involved in the creation of a new energy source based on hydrogen fusion. If and when successful, hydrogen fusion promises to turn the energy crisis into past history by providing an unlimited energy source virtually forever. The concept of hydrogen fusion began with astronomical observations of the fusion process in the sun. Spitzer was one of a handful of visionaries who foresaw bringing it down to earth.

In 1961, Lyman Spitzer was back at the observatory directing the Princeton Space Telescope project. A headline in the Daily Princetonian of September 26, 1962 reads, “Princeton Designs Satellite Schedule For ’65 Orbiting.” But form the outset a combination of technical and financial problems slowed the project.


SPACE TELESCOPE: This drawing of the OAO-C shows the components of the space vehicle that is carrying the 32-inch telescope, which, if so directed, could look down from tis 425-mile-high orbit and gaze steadily at the top of a man’s head.
Princeton Alumni Weekly. October 10, 1972.
John B. Rogerson, Jr., Professor of Astrophysical Sciences, took his Ph.D. in Astronomy at Princeton in 1954. He spent the year 1955-56 at the Mt. Wilson and Palomar observatories on a post-doctoral fellowship awarded by the Carnegie Foundation. He returned to Princeton in 1956 to work with Martin Schwarzschild, Eugen Higgins Professor of Astronomy, on the Stratoscope project with the understanding that he would be assigned to the Orbiting Astronomical Laboratory, if and when it materialized. It was Dr. Rogerson, as executive director of the Princeton Space Telescope Project, who handled the day-to-day working problems.

According to Schwarzschild, “Jack Rogerson’s decision at that point to commit himself to a project which could only have a black-or-white outcome – failure or success – and no in-between took fantastic courage.” It’s like an athlete training for the Olympics. Extraordinary endurance and persistence are demanded for the one and only chance. The Stratoscope Program under Schwarzschild’s direction was viewed as preparation for the orbiting telescope. “We had to learn,” says Schwarzschild, “how to control complex instrumentation from a distance and there were similarities in the types of technical problems encountered.” Nevertheless, the Stratoscope Program, which employed two huge balloons to carry telescopes to altitudes of some 80,000 feet produced some important scientific discoveries on its own. Stratoscope I (1957 and 1959), with a 12-inch telescope, obtained photographs of sunspots and granulation, showing sharp detail never seen before in photographs taken from the ground. The 36-inch diameter telescope of Stratoscope II (from 1965 until the present) obtained extraordinarily clear photographs of the planets Uranus and Jupiter. It also photographed the nuclei (central portions) of the Andromeda Nebula, its small elliptical companion, M32, and the Seyfert Galaxy, NGC 4151. A number of astronomers believe that the mysterious quasars are some form of the nuclei of galaxies.

John Rogerson’s hobby is electronics. A music lover, he has built his own high fidelity system. But it is questionable whether this equipped him to tackle the first of the satellite’s technical problems, a phenomenon known as high-voltage arcs. Batteries on the first OAO had died after only three days in space because space distorts the energy flow. High-voltage arcs were eliminated by Princeton scientists working as a team with engineers from Sylvania Electronic Systems, but only after a delay of a year. Since the university’s commitment is to pure scientific research and teaching, the design, testing and fabrication of all parts of the instrumentation were contracted out o Sylvania Electronic Systems of Needham, Mass., as prime contractor, and the Perkin-Elmer Corp. of Norwalk, Conn. As subcontractor for the optical system. At one point, according to Schwarzschild, the astronomer became an engineer when Rogerson contributed an idea for a very precise guidance system that no one else involved in the telescope or spacecraft fabrication would accept. He persuaded NASA to make test computations and the idea was adopted.

Between the inception and fabrication of Copernicus, a new generation of electronics was born. In 1966, after the initial design had been agreed on, the startling discovery that its electronics were obsolete forced a complete re-design. Another problem which plagued the project from the start was how to make the lightweight, high-precision mirror which was to become the biggest research mirror in space. Fortunately an entirely new technique, which involved fusing quartz into a convex egg crate pattern, evolved at that time. The astronomers have nothing but praise for the two companies. They point out that since it was impossible to create a set of design specifications at the outset, close cooperation and good will were at a premium. Though the pure scientific goal was never lost sight of, the creative capability of both industrial firms was expanded, resulting in unforeseen benefits. The large, fuse quartz discs are now being used as windows in wind tunnels as a result of optics experimentation for the Stratoscopes.

In 1968, eight years after the inception of the satellite program, the entire space program was reevaluated. The OAO projects became targets for elimination by a budget-conscious Congress. In previous years, renewal of funding was often so uncertain, that existing resources often would be stretched in order to maintain staffing while awaiting further allocation. In the end, NASA maintained its commitment to fundamental research and the project inched ahead.


NASA also supported Princeton’s Sounding Rocket Program, viewed as a forerunner of the OAO. Donald C. Morton, Senior Research Astronomer with rank of Professor in Astrophysical Sciences, took his Ph.D. at Princeton in 1959. He returned to Princeton after a two-year hiatus at the U.S. Naval Research Laboratory in November of 1961 to take charge of the Sounding Rocket Program. Sounding rockets, much smaller than rockets used for launching satellites, attain a height of about a few hundred miles before falling back to earth. To date, some 17 sounding rockets have been sent on brief, fiery flights. They have brought back the first far-ultraviolet spectra of hot stars, whose atmospheres will be further investigated by the Princeton Space Telescope. Through the Sounding Rocket Program, it was discovered that the most luminous of the hot stars are losing weight by ejecting matter into space at fantastic velocities, thereby signaling the beginnings of their “deaths.” Sounding rockets have, according to Dr. Morton, “photographer the ultraviolet spectra of the planets, Venus and Jupiter, with 50 times more detail than ever obtained before.” And most importantly, the Sounding Rocket Program has produced the first photographs of the stellar spectra with enough resolution to define the absorption lines, thus revealing the actual atomic composition of the universe itself. The first measurements of the interstellar abundance of oxygen, carbon and silicon within dark interstellar clouds, plus new detailed information on the distribution of hydrogen gas in our galaxy, were provided by Princeton’s Sounding Rocket Program.

Edward B. Jenkins, research staff, Astrophysical Sciences, joined Princeton’s Sounding Rocket Program in August 1966, after taking his Ph.D. at Cornell University. Jenkins’ involvement with the Princeton Space Telescope was specifically directed toward the telescope’s guidance system. He made the calculations and supervised the design of a system which guides the telescope by starlight so accurately that maximum variation is a three-foot error over a distance of 1,000 miles. Dr. Morton supervised and made calculations for the OAO spectrometer.

Two years ago, two young astronomers, Jerry F. Drake and Donald G. York, research associates in astrophysical sciences, were added to the staff. Permanently stationed at Goddard, they saw Copernicus through its final phase on a day-to-day basis and were specifically charged with originating the computer programs that control all the intricate operations of the telescope.


With the first transmission of stellar data on August 26 from the 4,900-pound, 83-million dollar satellite, some 425 miles in space, the 12-year goal was finally realized. Copernicus talks back once every orbit – every 100 minutes – to a computer at the Goddard Space Flight Center. By next month, a direct hookup to Peyton Hall’s basement computer will have been established, and Princeton’s astronomers will come home to work in familiar surroundings and to resume their academic routines. They will plot graphs, and from these graphs they will command photocells, which emit pulses for every light pulse they receive, to different locations in the spectrograph. The result will be something like a Rosetta Stone for the heavens.

In 1951, writing in the Smithsonian Institution’s Annual Report, Spitzer presented a theory of creation which pictured cosmic clouds as mothers of the stars. Now he will analyze whether clouds of rarefied gas which drift in the vast reaches of interstellar space, absorbing light from stars beyond them, have formed from the explosion of dying stars. “New stars,” says Dr. Spitzer, “are thought to arise, Phoenix-like, from the turbulent debris that makes up the interstellar clouds.” He will seek also the formation in space of complex organic molecules which are life’s pre-cursors.

The structure of the atmosphere of those young hot stars with short life cycles which are ejecting matter into the galaxy so rapidly will also be studied. Says Rogerson, “We are going to investigate the ashes of stars that have died or the seeds of stars to be born.” Finally, NASA is soliciting specific projects by outside astronomers so that the Princeton Space Telescope will, after an initial six-month period, be accommodated to outside research as well. (A second instrument, a set of three small telescopes designed to study the sources of X-rays in space and developed by the University College of London, England, is also aboard the satellite.)

At Peyton Hall, the Princeton Space Telescope will serve the university’s dual goals of teaching and research. Since the making of the telescope was such a long and uncertain process, students have not yet participated in the program but will be heavily involved in the analysis of the data. “Our most powerful means to train students,” says a department member, “is to have them take raw data and convert it to science.”


In trying to assess briefly the impact of Copernicus, Schwarzschild says that “with whomever you talk, the moment the topic of the universe comes about there is an entirely basic and natural curiosity and it is a curiosity that is innate to man…” The university’s courses in astronomy for the non-scientist are now running at about double the attendance of a few years ago. It is the Princeton reflection of a nation-wide phenomenon.

Spitzer hopes that the equipment aboard Copernicus will continue to operate for a year or longer. But, he says, “If it operates for only several months, we will achieve a large part of our objective. The pursuit of knowledge and the unraveling of the universe in which we live are great cultural challenges to mankind. Several hundred years from now, twentieth century man may be known by his successes in advancing the frontiers of knowledge.”

The Princeton team of astrophysicists is already looking ahead to a nearer future. By 1980 they hope to see the launching by NASA of a 120-inch multipurpose telescope. The Large Space Telescope, as it will be known, will weigh more than 20,000 pounds and will be launched from the Space Shuttle.

The ultimate significance of new knowledge about the cosmos is impossible to assess. Intuition whispers that we are as much related to the universe as we are to earth. The themes, birth, life, death and rebirth, so familiar to everyone from literature and myth, are being transferred by the astronomers to the cosmos, and Princeton’s Space Telescope is one step along a route that seeks to transform intuition into knowledge.

This was originally published in the October 10, 1972 issue of PAW.