First portrait of a brown dwarf.When it comes to heavenly featherweights, astronomers have detected low-mass stars and they have detected planets, but they have found nothing that has a mass in between. Now, researchers say they have discovered the missing link-an object considerably heavier than Jupiter but far less massive than a bona fide [Latin, In good faith.] Honest; genuine; actual; authentic; acting without the intention of defrauding. A bona fide purchaser is one who purchases property for a valuable consideration that is inducement for entering into a contract and without suspicion of being star. Researchers last week unveiled images of this unusual body. In October, Science News reported that Shrinivas Kulkarni Shrinivas Kulkarni is a professor of astrophysics and planetary science at Caltech. He is also on the Space Interferometry Mission science team and director of Caltech's optical observatories, including Palomar and Keck. Kulkarni is the brother of Sudha Murty. of the California Institute of Technology California Institute of Technology, at Pasadena, Calif.; originally for men, became coeducational in 1970; founded 1891 as Throop Polytechnic Institute; called Throop College of Technology, 1913–20. in Pasadena and his colleagues had obtained, but hadn't yet released, the first images and spectra of a faint body near the cool, red star GL229 (SN: 10/21/95, p.260). Many astronomers regard this body as the best candidate yet for a failed star, or brown dwarf brown dwarf, in astronomy, celestial body that is larger than a planet but does not have sufficient mass to convert hydrogen into helium via nuclear fusion as stars do. . They report their work in the Nov. 30 Nature and the Dec. 1 Science. On Nov. 17, Kulkarni's team used the Hubble Space Telescope Hubble Space Telescope (HST), the first large optical orbiting observatory. Built from 1978 to 1990 at a cost of $1.5 billion, the HST (named for astronomer E. P. Hubble) was expected to provide the clearest view yet obtained of the universe. to further view the object (SN: 11/25/95, p.358). In this Hubble image, the bright spot outside the glare from GL229 is the brown dwarf candidate, now called GL229B. The GL229B spectra indicate methane, which cannot survive at the surface temperatures of even the coolest stars. GL229B must therefore have a mass far less than 8 percent of the mass of the sun, the minimum needed to constitute a true star. "[T]here seems little question that it . . . bridges the gap between low-mass stars and Jupiter [the largest known planet]," comments theorist Frances Allard of Wichita State University Wichita State University (WSU) is an American state-supported university located in the city of Wichita, Kansas. WSU is one of six state universities governed by the Kansas Board of Regents. The current President is Dr. Donald Beggs. in Kansas. |
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