Columbia Encyclopedia

(Encyclopedia) grain, in agriculture, term referring to the caryopsis, or dry fruit, of a cereal grass. The term is also applied to the seedlike fruits of buckwheat and of certain other plants and is used collective...

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

(Encyclopedia) ultraviolet astronomy, study of celestial objects by means of the ultraviolet radiation they emit, in the wavelength range from about 90 to about 350 nanometers. Ultraviolet (UV) line spectrum measure...

(Encyclopedia) ring, in astronomy, relatively thin band of rocks and dust and ice particles that orbit around a planet in the planet's equatorial plane. All four of the giant planets in the solar system—Jupiter, S...

(Encyclopedia) Pluto, in astronomy, a dwarf planet and the first Kuiper belt, or transneptunian, object (see comet) to be discovered (1930) by astronomers. Pluto has an elliptical orbit usually lying beyond that of ...

(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 ...

(Encyclopedia) Mars, in astronomy, 4th planet from the sun, with an orbit next in order beyond that of the earth. Mars has two natural satellites, discovered by Asaph Hall in 1877. The innermost of these, Phobos...

(Encyclopedia) Piazzi, Giuseppe jo͞ozĕpˈpā pyätˈtsē [key], 1746–1826, Italian astronomer, a Theatine priest from 1769. He became (1781) professor of mathematics at the Univ. of Palermo, supervised construct...

(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.,...

(Encyclopedia) Demeter dĭmēˈtər [key], in Greek religion and mythology, goddess of harvest and fertility; daughter of Kronos and Rhea. She was the mother of Persephone by Zeus. When Pluto abducted Persephone, De...