The Astronomy Portal
(from Astronomy Greek: ἀστρονομία, literally meaning the science that studies the laws of the stars) is a natural science that studies celestial objects and phenomena. It uses mathematics, physics, and chemistry in order to explain their origin and evolution. Objects of interest include planets, moons, stars, nebulae, galaxies, and comets. Relevant phenomena include supernova explosions, gamma ray bursts, quasars, blazars, pulsars, and cosmic microwave background radiation. More generally, astronomy studies everything that originates beyond Earth's atmosphere. Cosmology is a branch of astronomy that studies the universe as a whole.
Astronomy is one of the oldest natural sciences. The early civilizations in
recorded history made methodical observations of the night sky. These include the Babylonians, Greeks, Indians, Egyptians, Chinese, Maya, and many ancient indigenous peoples of the Americas. In the past, astronomy included disciplines as diverse as astrometry, celestial navigation, observational astronomy, and the making of calendars. Nowadays, professional astronomy is often said to be the same as astrophysics.
Professional astronomy is split into
observational and theoretical branches. Observational astronomy is focused on acquiring data from observations of astronomical objects. This data is then analyzed using basic principles of physics. Theoretical astronomy is oriented toward the development of computer or analytical models to describe astronomical objects and phenomena. These two fields complement each other. Theoretical astronomy seeks to explain observational results and observations are used to confirm theoretical results.
Astronomy is one of the few sciences in which amateurs play an
active role. This is especially true for the discovery and observation of transient events. Amateur astronomers have helped with many important discoveries, such as finding new comets. ( )
Full article... General images -
The following are images from various astronomy-related articles on Wikipedia.
Calendrical functions of the
9th-century diagram of the positions of the
An amateur astrophotography setup with an automated guide system connected to a laptop. (from
One of the Oldest Observatories in
50 cm refracting telescope at
who became Head of the Mathematical Board and Director of the Observatory of the Chinese emperor in 1669 (from
Portrait of the Flemish astronomer
Cat's Paw Nebula
created combining the work of professional and amateur astronomers. The image is the combination of the 2.2-metre MPG/ESO telescope of the La Silla Observatory in Chile and a 0.4-meter amateur telescope. (from
An image of the
Ultra HD photography taken at
Historical accuracy of atomic clocks from
is the world's most powerful telescope for studying the Universe at submillimeter and millimeter wavelengths. (from
"El Caracol" observatory temple at
Did you know -
More Did you know (auto generated) WikiProjects Selected image -
Credit: English Wikipedia en:user:Friendlystar
NGC 2371-2 is a dual lobed planetary nebula located in the constellation Gemini. At 13th magnitude, this nebula is well within the limits of most amateur telescopes.
More selected pictures
Astronomy News January anniversaries
1 January 1925 – Astronomer
Edwin Hubble formally presents his discovery of galaxies outside the Milky Way at a meeting of the American Astronomical Society 1 January 1952 – The
Kyiv Planetarium opens in Kyiv, Ukraine 3 January 1888 – The 91-centimeter
refracting telescope at Lick Observatory, the world's largest telescope from 1888 to 1897, sees its first light 3 January 1999 – The
Mars Polar Lander is launched by NASA to study the soil and climate of Planum Australe, a region near the south pole on Mars 4 January 2004 – The
Mars rover lands, three weeks ahead of twin rover Spirit , and begins exploring the Red Planet Opportunity 14 January 2005 – The probe
lands on Huygens Titan, a moon of Saturn, in the first successful landing in the outer Solar System 26 January 1949 – Hale telescope, which introduced several innovations to telescope construction and was the world's largest telescope for nearly 30 years, has its first light
UT unless otherwise specified.
1 January, 23:00 Moon at perigee
2 January, 18:33 New moon
3 January, 20:56 Peak of Quadrantids meteor shower
4 January, 00:59 Earth at perihelion
7 January, 10:59 Mercury at greatest eastern elongation
9 January, 00:50 Venus at inferior conjunction
14 January, 09:27 Moon at apogee
17 January, 23:48 Full moon
23 January, 10:25 Mercury at inferior conjunction
30 January, 07:09 Moon at perigee
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