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Dioscuri

(Encyclopedia)Dioscuri: see Castor and Pollux. ...

gamma-ray astronomy

(Encyclopedia)gamma-ray astronomy, study of astronomical objects by analysis of the most energetic electromagnetic radiation they emit. Gamma rays are shorter in wavelength and hence more energetic than X rays (see...

X-ray astronomy

(Encyclopedia)X-ray astronomy, study of celestial objects by means of the X rays they emit, in the wavelength range from 0.01 to 10 nanometers. X-ray astronomy dates to 1949 with the discovery that the sun emits X ...

Polydeuces

(Encyclopedia)Polydeuces pŏlˌĭdo͞oˈsēs [key]: see Castor and Pollux. ...

Gemini

(Encyclopedia)Gemini jĕmˈənī, –nē [key] [Lat.,=the twins], northern constellation lying on the ecliptic (the sun's apparent path through the heavens) between Taurus and Cancer, N of Canis Minor; it is one of...

In

(Encyclopedia)In, symbol for the element indium. ...

National Radio Astronomy Observatory

(Encyclopedia)National Radio Astronomy Observatory (NRAO), federal observatory for radio astronomy, founded in 1956 and operated under contract with the National Science Foundation by Associated Universities, Inc.,...

Nuffield Radio Astronomy Laboratories

(Encyclopedia)Nuffield Radio Astronomy Laboratories: see Jodrell Bank Observatory. ...

cesium

(Encyclopedia)cesium sēˈzēəm [key] [Lat.,=bluish gray], a metallic chemical element; symbol Cs; at. no. 55; at. wt. 132.90545; m.p. 28.4℃; b.p. 669.3℃; sp. gr. 1.873 at 20℃; valence +1. Cesium is a ductil...

Helen

(Encyclopedia)Helen, in Greek mythology, the most beautiful of women; daughter of Leda and Zeus, and sister of Castor and Pollux and Clytemnestra. While still a young girl Helen was abducted to Attica by Theseus an...