Cosmic survey yields surprise.When astronomers last year used a balloon-borne telescope to observe a small patch of sky in the far infrared, they were intent only on studying the faint microwave glow left over from the birth of the universe. But they now report that their 10-hour survey may have uncovered a puzzling new class of objects. Edward S. Cheng of NASA's Goddard Space Flight Center The Goddard Space Flight Center (GSFC) is a major NASA space research laboratory established on May 1, 1959 as NASA's first space flight center. GSFC employs approximately 10,000 civil servants and contractors, and is located approximately 6.5 miles northeast of Washington, D.C. in Greenbelt, Md., and his colleagues launched the far-infrared telescope to search for faint hot and cold spots in the cosmic microwave background Noun 1. cosmic microwave background - (cosmology) the cooled remnant of the hot big bang that fills the entire universe and can be observed today with an average temperature of about 2. . Such temperature fluctuations may signify primordial lumps that later gave rise to the present-day collection of galaxies and galaxy clusters This page lists some of the more interesting galaxy clusters and groups. Defining the limits of galaxy clusters is imprecise as many clusters are still forming. In particular, clusters close to the Milky Way tend to be classified as galaxy clusters even when they are much smaller . The team's experiment, known as the Medium-Scale Anisotropy anisotropy /an·isot·ro·py/ (an?i-sot´rah-pe) the quality of being anisotropic. anisotropy (an´āsôt´r Measurement (MSAM MSAM MetaFrame Secure Access Manager (Citrix) MSAM Medium Scale Anisotropy Measurement MSAM Microcomputer Spectrum Analysis Models MSAM Multi-Sequential Access Method MSAM Major System Acquisition Manual MSAM Microsoft Screen Access Model ), measured the temperature variation in the microwave background over patches of sky 0.5 degrees in diameter--the width of the full moon on the sky. MSAM found that the temperature varied by about one part in 100,000. But MSAM also detected two luminous, point-like sources of radiation that don't appear to be part of the microwave background. Moreover, the sources don't correspond to any objects compiled in well-known infrared and radio-wave catalogs, says Cheng. He adds that MSAM detected these puzzling emissions only at the two longest far-infrared wavelengths in the survey -- 1.1 and 1.8 millimeters. Cheng speculates that the sources might be distant, radio-quiet quasars Proper naming of quasars are by Catalogue Entry, Qxxxx±yy using B1950 coordinates, or QSO Jxxxx±yyyy using J2000 coordinates. This page lists quasars.
Electromagnetic energy of the frequency range corresponding to that used in radio communications, usually 10,000 cycles per second to 300 billion cycles per second. below a certain frequency or is surrounded by material that absorbs radio waves. "This is the beginning of a hunting expedition," he notes. Cheng says he's of two minds about the findings. On the one hand, they could represent the first celestial sources discovered by observing in the far infrared. On the other hand, if the sky is littered with such point-like sources, it will make the task of deciphering the structure of the microwave background at small angular scales far more difficult. |
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