Chandrasekhar: The man behind the scope Analysis/Commentary A few years ago, black holes were considered almost supernatural; now they resurface as some of the basic elements of the universe around us. The NASA Chandra X-ray telescope organization announced yesterday that two teams of scientists using the new NASA device, in orbit, have found that stellar-size black holes are common in deep space and can be observed going back 12 billion years. (Telescopes like the Hubble and Chandra look back in time by focusing on radiation transmitted ages ago but reaching the earth only now.) Chandrasekhar, the man for whom the telescope is named, was properly called Subrahmanyan Chandrasekhar. He taught astrophysics at the University of Chicago from 1937 until his death in 1995. He allowed his colleagues and pupils to refer to him by the nickname "Chandra," and NASA continues the custom in naming the telescope. The Chandra "X-Ray Observatory," launched in June 1999, filters high-frequency emissions coming from hot objects. X-rays, while invisible to the human eye, represent a common form of heat radiated by galaxies, neutron stars, and gases surrounding black holes. Converted into computer images, X-rays serve as an excellent tool for analyzing astral bodies beyond our solar system. The Chandra telescope has a five-year lifetime and orbits the earth two hundred times farther out than the Hubble. It maintains an elliptical orbit, stretching to one-third the distance to the moon. This extended orbit allows it to avoid the earth's own radiation fields, while it also avoids the negative effects of the sun's light by means of a sun shield. Chandrasekhar was born in 1910 in an area that now belongs to Pakistan. His father was a successful official with the Indian railway, and his uncle was a Nobel-winning physicist. During his teen years, Chandrasekhar witnessed the formation of modern India and received an Indian government scholarship to study in Cambridge, England. In 1933, he passed his doctoral exams at Trinity College, and in 1937 he moved to the United States to teach. (He became a U.S. citizen in 1953.) In the 1930s, working with English scientist W. H. Fowler, a specialist in "white dwarf" (newly minted) stars, Chandrasekhar defined the mathematics of "star lives." Stars either attain longevity (like our sun) or explode in short-lived brilliance. Using Einstein's predictions, Chandrasekhar proved there was a limit to normal star formation. His law was simple: stars with more than 1.44 solar masses are doomed to explode as supernovas or to become pulsating neutron stars; stars with less than 1.44 solar masses will either live out normal lives like our sun, or will never quite attain fusion and will fizz out like ashes. This law -- the Chandra limit -- has become a key resource in the toolbag of astrophysics. He received the Nobel prize in 1983 for his research, and continued to work on the "nucleosynthesis" of stars -- the production of chemical elements deep in the core of exploding stars. Chandrasekhar wrote a short autobiography, saying that his wife, Lalitha Doraiswamy, through her patient understanding, support, and encouragement, was "one of the central facts of his life." Like Einstein, he made room in his life for humanism. Chandrasekhar was enthralled by stars and their formation, and by the mechanics of black holes. Now the X-ray telescope named after him seems to have begun to contribute significantly to what science knows about them. Scientists look forward to understanding how galaxies develop around black holes and how nebulae (clouds) and galaxies give birth to solar systems and their planets. March 14, 2001