Portal:Astronomy

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The Astronomy Portal

Introduction

Astronomy (from 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 outside 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 - load new batch

The following are images from various astronomy-related articles on Wikipedia.

Image 1Mayall telescope at Kitt Peak National Observatory (from Observational astronomy)
Image 2Sir Patrick Moore was one of the world's leading popularisers of astronomy. (from Amateur astronomy)
Image 3An image of the 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 Amateur astronomy)
Image 4Babylonian tablet in the British Museum recording Halley's comet in 164 BC. (from History of astronomy)
Image 5"El Caracol" observatory temple at Chichen Itza, Mexico. (from History of astronomy)
Image 6Historical Jantar Mantar observatory in Jaipur, India. (from History of astronomy)
Image 7Places like Paranal Observatory offer crystal clear skies for observing astronomical objects with or without instruments. (from Amateur astronomy)
Image 850 cm refracting telescope at Nice Observatory. (from Observational astronomy)
Image 9Telescope set up in Brooklyn Bridge Park for a public stargazing session (from Amateur astronomy)
Image 10History of the Universe – gravitational waves are hypothesized to arise from cosmic inflation, a faster-than-light expansion just after the Big Bang (from Physical cosmology)
Image 11An amateur astrophotography setup with an automated guide system connected to a laptop. (from Observational astronomy)
Image 12Chart from Senemut's tomb, 18th dynasty (from History of astronomy)
Image 13Comparison of CMB (Cosmic microwave background) results from satellites COBE, WMAP and Planck documenting a progress in 1989–2013. (from History of astronomy)
Image 14The main platform at La Silla hosts a huge range of telescopes with which astronomers can explore the Universe. (from Observational astronomy)
Image 159th-century diagram of the positions of the seven planets on 18 March 816, from the Leiden Aratea. (from History of astronomy)
Image 16Calendrical functions of the Berlin Gold Hat c. 1000 BC (from History of astronomy)
Image 17One of the Oldest Observatories in South America is the Quito Astronomical Observatory, founded in 1873 and located 12 minutes south of the Equator in Quito, Ecuador. The Quito Astronomical Observatory is the National Observatory of Ecuador and is located in the Historic Center of Quito and is managed by the National Polytechnic School. (from Observational astronomy)
Image 18Sunset at the equinox from the prehistoric site of Pizzo Vento at Fondachelli Fantina, Sicily (from History of astronomy)
Image 19The Nebra sky disk Germany 1600 BC (from History of astronomy)
Image 20The Antikythera Mechanism was an analog computer from 150–100 BC designed to calculate the positions of astronomical objects. (from History of astronomy)
Image 21Hubble Space Telescope. (from History of astronomy)
Image 22Ultra HD photography taken at La Silla Observatory. (from Observational astronomy)
Image 23The Astronomer, 1668, by Johannes Vermeer (from Astronomer)
Image 24Arabic astrolabe from 1208 AD (from History of astronomy)
Image 25Historical accuracy of atomic clocks from NIST. (from Theoretical astronomy)
Image 26ALMA is the world's most powerful telescope for studying the Universe at submillimeter and millimeter wavelengths. (from Observational astronomy)
Image 27Portrait of the Flemish astronomer Ferdinand Verbiest who became Head of the Mathematical Board and Director of the Observatory of the Chinese emperor in 1669 (from Astronomer)
Image 28An assembly in Estonia to observe meteors (from Observational astronomy)

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This is a Featured article, which represents some of the best content on English Wikipedia..

Eris, the largest known scattered-disc object (center), and its moon Dysnomia (left of object)

The scattered disc (or scattered disk) is a distant circumstellar disc in the Solar System that is sparsely populated by icy small solar system bodies, which are a subset of the broader family of trans-Neptunian objects. The scattered-disc objects (SDOs) have orbital eccentricities ranging as high as 0.8, inclinations as high as 40°, and perihelia greater than 30 astronomical units (4.5×10⁹ km; 2.8×10⁹ mi). These extreme orbits are thought to be the result of gravitational "scattering" by the gas giants, and the objects continue to be subject to perturbation by the planet Neptune.

Although the closest scattered-disc objects approach the Sun at about 30–35 AU, their orbits can extend well beyond 100 AU. This makes scattered objects among the coldest and most distant objects in the Solar System. The innermost portion of the scattered disc overlaps with a torus-shaped region of orbiting objects traditionally called the Kuiper belt, but its outer limits reach much farther away from the Sun and farther above and below the ecliptic than the Kuiper belt proper. (Full article...)

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Did you know - show different entries

... that 12th-century Muslim scientist Al-Khazini, who proposed a theory of gravitation long before Isaac Newton, was, in his early life, a slave of the Seljuq Turks?
... that Kepler-47c is a circumbinary planet orbiting in the habitable zone of Kepler-47, a binary star system?
... that two high school students used the automated telescope at Leuschner Observatory to record the earliest images of supernova SN 1994I?
... that the Kuiper crater in the Kuiper quadrangle, named after Dutch American astronomer Gerard Kuiper, has the highest albedo recorded on Mercury?
...that Mt. Olympus Mons on Mars is the highest peak in the solar system?

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WikiProjects

WikiProject Astronomy	WikiProject Solar System



WikiProject Cosmology	WikiProject Spaceflight

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Selected image - show another

Credit: User:Hewholooks

IC 405, also Sharpless 229 (Sh2-229), Caldwell 31 and The Flaming Star Nebula, is an emission/reflection nebula and a Caldwell object in the constellation Auriga, surrounding the bluish star AE Aurigae. It shines at magnitude +6.0. The nebula is about 5 light-years across. This is a white light image of the Flaming Star Nebula showing the "smoke" of reflection nebula.

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Astronomy News

26 May 2021 – May 2021 lunar eclipse: A total lunar eclipse occurs, the second-shortest of the 21st century, with totality lasting for only 14 minutes. Nicknamed the Super Flower Blood Moon, the eclipse was visible over the Pacific Ocean and Oceania, with South and East Asia seeing the eclipse at moonrise, and the Americas seeing the eclipse at moonset. (Space.com)
17 February 2021 – Discoveries of exoplanets: Astronomers announce the discovery of HD 110082 b, a sub-Neptune exoplanet that is three times larger than Earth and which orbits a relatively young star. (Phys.org)

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June anniversaries

2 June 1966 – Surveyor 1 lands on the moon, first US spacecraft to do so
3 June 1966 – Gemini 9 (Gemini Titan 9A) launch from Cape Canaveral, Florida
19 June 1976 – The Viking 1 orbiter arrives in Mars orbit
24 June 2004 – First private spaceflight, SpaceShipOne piloted by Mike Melvill
27 June 1966 – Galileo probe, flyby of Ganymede (Jupiter's largest moon)
30 June 2001 – The NASA Explorer mission, MAP (Microwave Anisotropy Probe), is launched to measure the temperature of cosmic background radiation (remnant heat from the Big Bang)

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Space-related Portals

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Astronomical events

All times UT unless otherwise specified.

8 June, 02:27	Moon at apogee
10 June, 10:42	New moon and annular solar eclipse
11 June, 01:06	Mercury at inferior conjunction
21 June, 03:32	Earth northern solstice
23 June, 09:58	Moon at perigee
24 June, 18:40	Full moon