Observational astronomy Reference Libraries

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2014-01-12 00:00:00

Image Caption: NGC 4414, a typical spiral galaxy in the constellation Coma Berenices, is about 56,000 light-years in diameter and approximately 60 million light-years distant. Credit: NASA/ESA/Wikipedia What is Astrophysics? For much of the modern age the term Astrophysics has been used synonymously with Astronomy. This interchange is so common that many textbooks even offer the two as...

Radio Telescope
2010-10-08 17:45:24

Radio telescopes, used in tracking and collecting data from satellites and space probes, are a form of directional radio antenna used in radio astronomy. They operate on the radio frequency portion of the electromagnetic spectrum where they detect radio sources. Radio telescopes are large parabolic antennas used singly or in an array and are located far from major centers of population in...

2010-09-24 17:50:57

A telescope, designed to aid the observation of remote objects, collects some form of electromagnetic radiation (such as visible light). The Netherlands developed the first known practical telescope in the 17th century. The term "telescope" was termed in order to describe Galileo's instruments in 1611. However, Galileo was not the inventor of the telescope. It was Hans Lippershey, Zacharias...

2014-01-12 00:00:00

Sample Entry: Astronomy is the scientific study of stars, planets, comets, galaxies, and other phenomena that occur outside Earth's atmosphere (e.g. cosmic radiation). Astronomy deals with the evolution, physics, chemical makeup, meteorology, and motion of celestial objects, and also the formation of the universe. The word Astronomy comes from the Greek words astron (meaning "star") and...

Webb Thomas William
2009-04-28 11:47:36

The Reverend Thomas William Webb (December 14, 1807 "“ May 19, 1885) was a British astronomer and faithful clergyman. The lone son of a clergyman, the Rev. John Webb was raised and educated by his father in absence of his mother who died in Webb's early childhood. He travelled to Oxford to attend Magdalen College. Soon after, he was ordained a minister by the Anglican Church in 1829. In...

2004-10-19 04:45:44

Sky -- Although almost everyone have seen it, sky is hard to be defined precisely. Generally, sky is the space seen when one looks upward from the surface of a planet. Some people define sky as the denser gaseous zone of a planet's atmosphere. Clouds, rainbows and weather all occur amongst a planet's sky. In astronomy, the sky is divided into many regions, called constellations. The...

2004-10-19 04:45:44

Scintillation -- Scintillation is a generic term for rapid variations in apparent position, brightness, or color of a distant luminous object viewed through the atmosphere. If the object lies outside the earth's atmosphere, as in the case of stars and planets, the phenomenon is termed astronomical scintillation; if the luminous source lies within the atmosphere, the phenomenon is termed...

X-Ray Astronomy
2004-10-19 04:45:44

X-Ray Astronomy -- Although the more energetic X-rays (E > 30 keV) can penetrate the air at least for distances of a few meters (they would never have been detected and medical X-ray machines would not work if this was not the case) the Earth's atmosphere is thick enough that virtually none are able to penetrate from outer space all the way to the Earth's surface. X-rays in the 0.5 - 5 keV...

Very Large Telescope
2004-10-19 04:45:43

Very Large Telescope -- The Very Large Telescope (VLT) consist of four optical telescopes that have 8.4 meter aperture. The VLT is a project of the European Southern Observatory organization. It is located at the Paranal Observatory on Cerro Paranal, a 2,635-m high mountain in the Atacama desert in northern Chile. The VLT consists of a cluster four of large telescopes, and an...

Very Large Array
2004-10-19 04:45:43

Very Large Array -- The Very Large Array, one of the world's premier astronomical radio observatories, consists of 27 radio antennas in a Y-shaped configuration on the Plains of San Agustin fifty miles west of Socorro, New Mexico. Each antenna is 25 meters (82 feet) in diameter. The data from the antennas is combined electronically to give the resolution of an antenna 36km (22 miles)...

Word of the Day
  • Licking.
  • Hence Running along or over a surface, as if in the act of licking; flowing over or along; lapping or bathing; softly bright; gleaming.
This word comes the Latin 'lambere,' to lick.