Non-optical Telescopes

By the middle of the twentieth century, astronomers realized that stars emit the full spectrum of electromagnetic radiation. That was both good and bad news. The good news was that high energy emissions, such as X-rays and radio waves, would be detectable on Earth. Designers immediately began work on telescopes that could detect these emissions. The bad news was that low-energy emissions, such as infrared radiation, would not penetrate the Earth’s atmosphere. Detection of the infrared emissions put out by a star would have to be detected by telescopes away from the Earth. Astronomers eagerly developed satellite telescopes and launched the first X-ray telescope in 1970, shown here. It was named Uhuru, which means “freedom” in Swahili, the language of Kenya, where it rocketed into space.

   At the U.S. Naval Research Observatory, she worked in radio astronomy and was soon named head of the microwave spectroscopy section. Roman loved research. But a chance observation made earlier in West Texas was about to change her career completely.

   While collecting data on high velocity stars at McDonald Observatory, she noticed that a star she was studying did not match the published data about it. The information described the star as being very like our own Sun. But Roman saw that it was very different. “It didn’t look anything at all like the Sun,” she said. She published her observation in a short paper in The Astrophysical Journal and thought no more about that star. Others did think about it, however.

   Her short paper caught the attention of a Russian astronomer, who invited her to be a speaker at the dedication of a major new Russian observatory. She was one of just three American astronomers invited to the event, and her public trip to Russia generated headlines in U.S. newspapers. The publicity brought Roman to the attention of NASA administrators. “I was asked if I knew anyone who would like to set up a program in space astronomy,” she said in an interview. “I knew that taking on that responsibility would mean that I could no longer do forefront research. But the challenge of starting with a clean slate, to formulate a program that would influence astronomy for decades to come, was too great to resist.”
   For nearly twenty years, Nancy Roman designed the orbiting instruments that detect and measure gamma rays, radio waves,
X-rays, and visible light. Among Roman’s satellite observatories were three solar observatories that use ultraviolet light and X-rays to study the Sun. She was also responsible for the launch of three small astronomical satellites that use X-ray and gamma-rays to study the sky, one International Ultraviolet Explorer, and four astronomical observatories that make optical and ultraviolet measurements.

   The programs she directed gave astronomers important information about planet surfaces and led to the successful Viking probes that landed on Mars in 1976. Roman helped design and produce nearly all the orbiting observatories launched during the 1970s and 1980s. She collected data from the ultraviolet and X-ray detecting Copernicus satellite in 1972, and from the U.S. space station Skylab that circled the Earth from 1973 until 1979.