A newly discovered celestial body appears to be the largest object that scientists have found in the solar system since their detection of Pluto in 1930. Designated 2002 LM60, it’s unofficially known as Quaoar (pronounced Kwa-whar) after a Native American god.

Residing in the Kuiper belt, the reservoir of comets and other frozen bodies beyond the orbit of Neptune, Quaoar measures 1,300 kilometers in diameter, more than half the width of Pluto. Along with the finding of several other Kuiper belt behemoths over the past 2 years, the discovery suggests the region may harbor even larger bodies.

Michael E. Brown and Chadwick A. Trujillo of the California Institute of Technology in Pasadena reported Quaoar’s discovery this week at the annual meeting of the American Astronomical Society’s Division for Planetary Sciences in Birmingham, Ala.

Brown and Trujillo found Quaoar on an image taken June 4 with a 48-inch telescope at Palomar Observatory near Escondido, Calif. Looking through archival images recorded at Palomar, the scientists also identified Quaoar in images from 1982, 1996, 2000, and 2001. Because they could trace the path of the body over a 20-year period, the astronomers were able to determine Quaoar’s orbit and distance from Earth. The researchers then made further observations with two other detectors, including the Hubble Space Telescope.

Quaoar orbits the sun every 288 years in a near-perfect circle inclined by 7.9 degrees relative to the plane in which every planet but Pluto travels. Many astronomers now assert that Pluto is itself a Kuiper belt object that got knocked into a highly inclined elliptical orbit that crosses the orbit of Neptune (SN: 6/9/01, p. 360: Available to subscribers at http://www.sciencenews.org/20010609/bob8.asp.). With several large objects now known to belong to the Kuiper belt, Pluto’s size no longer makes the body an oddity in the belt.

“Quaoar definitely hurts the case for Pluto being a planet,” Brown says.

Some astronomers had calculated that another Kuiper belt object, now known as Ixion (SN: 7/21/01, p. 41: Available to subscribers at http://www.sciencenews.org/20010721/note10.asp.), is almost as big as Quaoar. But that result is highly uncertain, says Ixion codiscoverer Robert L. Millis, director of the Lowell Observatory in Flagstaff, Ariz. Ixion hasn’t been observed with a telescope, such as Hubble, that could measure its size directly or with a submillimeter telescope, which determines the object’s temperature, information that can be used to calculate size. Quaoar, however, was observed with both Hubble and a submillimeter telescope.

Two other recently discovered Kuiper belt objects, also observed with submillimeter telescopes, each have a diameter of about 900 km.

“It would seem quite likely that there are a few Pluto-sized objects, maybe even Mars-sized objects” that lie farther out than Quaoar in the Kuiper belt, says Brian G. Marsden of the Harvard-Smithsonian Center for Astrophysics in Cambridge, Mass.

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An article written by two LSU researchers about their breakthrough discovery in the field of physics was published in the Jan. 11 issue of Nature magazine – one of the world’s most prestigious scientific journals.

The article, titled “Quantum metallicity in a two-dimensional insulator,” detailed significant new findings by professor Philip W. Adams and postdoctoral researcher Vladimir Y. Butko of the LSU Department of Physics and Astronomy.

The pair have been working to find out why metals stop being good conductors of electricity after reaching a certain thinness. Adams said many scientists have been trying to research this question by vaporizing metals and allowing the vapors to settle on other surfaces as a thin film. Then, they try to test the film for conductivity. However, he said studies have been problematic because the vapors of most metals fall in droplets, creating a film that is granular, making testing difficult and inaccurate.

But Adams and Butko found that vaporized beryllium makes a smooth film that is perfect for testing the effects of thinness. They found that ultra-thin beryllium films do not conduct electricity very well, mainly because the electrons in the material do not flow well. However, when they applied a magnetic field to the film, its resistance to conductivity dramatically decreased. The more the researchers increased the magnetic field, the more the beryllium’s resistance fell, until finally, the resistance stabilized at what is known to physicists as the “quantum resistance.”

The researchers said that when a magnetic field was applied, the metal film always found its way back to the same resistance. They believe that all metals react the same way and that this behavior was never previously observed because the granular films of other metals were so difficult to test. The key to this theory is that beryllium is not even magnetic, so the fact that a magnetic field would so drastically change the conductivity of that metal is a great surprise.

Adams said this discovery is significant because it shows that there is a universal standard for limiting a metal film’s resistance to conductivity and that the standard is based on the behavior of electrons in metals when exposed to magnetic fields. Adams said these findings are important enough to be included in textbooks in the future.

Adams, who has been a member of the LSU faculty since 1988, said the discovery has gained much attention for his postdoctoral researcher. He said that Butko, who is also a faculty member at the Ioffe Physical Technical Institute in St. Petersburg, Russia, has received numerous offers of employment since the article was published in Nature. He has been offered postdoctoral research positions at Cornell University and the University of Chicago and is interviewing for faculty positions at several research universities in the U.S.

Published weekly in London, Nature contains only a handful of research articles and letters in each issue. It covers all areas of science, with only a couple of items dealing with physics and materials science each week. Several LSU researchers have been published in Nature in the past year, including associate professor John DiTusa, also of the Department of Physics and Astronomy.

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