A Star Is Born

Visible only through powerful tele scopes, the star R Monocerotis glows faintly in the constellation of Unicorn. For years it has been considered a puzzling "dwarf" that lived in the Milky Way; astronomers could not explain either its dimness or its complex spectrum. Now, as they have long suspected, they have learned that there is much more to the obscure star than meets the eye. In an article in Nature, Astrophysicist Frank Low, 33, and Rice University Graduate Student Bruce Smith, 23, report that R Monocerotis (R designates the star; Monocerotis is Latin for uni corn) may well be a vigorous young star surrounded by the beginnings of a planetary system.

Astrophysicist Low, who is on the staff of both the University of Arizona and Rice, turned his attention to R Mon, as it is called, while searching for stars in the process of formation. "We knew that stars must be forming in the universe around us," he says. And wherever they were, those new stars should have been extremely bright. But strangely, none could be found. Then Low learned from a visiting astronomer that R Mon seemed to be emitting an abnormally large amount of infra-red radiation. He decided to check on the star with his germanium bolometer, an extremely sensitive infra-red measuring device of his own design (TIME, Dec. 17, 1965).

Mathematical Model. After connecting the bolometer to the 5-ft. infra-red telescope at the University of Arizona's Catalina observatory near Tucson, Low made careful measurements of R Mon's total energy output over a wide range of wave lengths. He found that the energy produced was much greater than earlier observations had indicated (about 870 times that of the sun), and the star was radiating with inexplicable intensity at the longest wave lengths. On the theory that something was obscuring the visible light, Low asked Smith to help work out a mathematical model of a bright, hot star that was surrounded by a thick blanket of gas and dust.

Starting with a mathematical model of the present distribution of interplanetary dust, they produced a set of equations describing the primitive solar system when, like R Man, it was surrounded by a vast cloud of dust. Low checked the predictions of this model against his R Mon readings, and found an almost perfect match.

Contracting Cloud. Though R Mon is a near neighbor, only 2,000 light-years away, its characteristics have universal implications. Most astronomers agree that the sun formed from a slowly rotating nebula--a cloud of dust and gas that gradually contracted because of gravitation, and began to rotate faster. When pressures at the dense center of the shrinking cloud produced enough heat, thermonuclear reactions took place and the sun began to burn, still surrounded by the outlying portions of the cloud--apparently the current state of R Man's evolution. As more of the particles fell toward the burning center, or collected into orbiting globs of matter that eventually formed the planets, the light of the central nuclear fire began to penetrate the thinning cloud. Eventually the sun became clearly visible to the outside universe.

Low and Smith are now investigating infra-red readings from a dozen other stars. If these prove to be young stars obscured in the center of dusty nebulae, they will present strong evidence that most, if not all stars develop from nebulae. This, in turn, would support a growing belief that the formation of planets is the rule--rather than the rare exception--in the evolution of stars. Thus, among the multitude of stars--there are 100 billion in the Milky Way Galaxy alone, and as many as 100 billion galaxies in the universe--there may well be billions upon billions of planets that were formed in much the same way as the earth. Which suggests that, like the earth, many of them might be hospitable to intelligent life.

This file is automatically generated by a robot program, so reader's discretion is required.