Portal:Astronomy

Portal topics: Activities; Culture; Geography; Health; History; Mathematics; Nature; People; Philosophy; Religion; Society; Technology; Random portal

The Astronomy Portal

Introduction

Astronomy (from Ancient Greek ἀστρονομία (astronomía) '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 - load new batch

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

Image 1Babylonian tablet in the British Museum recording Halley's comet in 164 BC. (from History of astronomy)
Image 2An assembly in Estonia to observe meteors (from Observational astronomy)
Image 3The Nebra sky disk, Germany, 1800-1600 BC (from History of astronomy)
Image 4History 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 5The Crab Nebula as seen in various wavelengths (from Observational astronomy)
Image 6Ultra HD photography taken at La Silla Observatory. (from Observational astronomy)
Image 7An 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)
$Image 850 cm refracting telescope at Nice Observatory. (from Observational astronomy)$

Image 850 cm refracting telescope at Nice Observatory. (from Observational astronomy)
Image 9"El Caracol" observatory temple at Chichen Itza, Mexico. (from History of astronomy)
Image 10One of the rolls of amateur astronomy groups is outreach programs bringing astronomy to the general public (from Amateur astronomy)
Image 11The Northern Hemisphere page from Johann Bayer's 1661 edition of Uranometria - the first atlas to have star charts covering the entire celestial sphere (from History of astronomy)
Image 12Sir Patrick Moore was one of the world's leading popularisers of astronomy. (from Amateur astronomy)
Image 13Map of the Milky Way Galaxy with the constellations that cross the galactic plane in each direction and the known prominent components annotated including main arms, spurs, bar, nucleus/bulge, notable nebulae and globular clusters. (from History of astronomy)
Image 14Portrait 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 15Historical Jantar Mantar observatory in Jaipur, India. (from History of astronomy)
Image 16Calendrical functions of the Berlin Gold Hat c. 1000 BC (from History of astronomy)
Image 17An amateur astrophotography setup with an automated guide system connected to a laptop. (from Observational astronomy)
Image 18Comparison of CMB (Cosmic microwave background) results from satellites COBE, WMAP and Planck documenting a progress in 1989–2013. (from History of astronomy)
Image 19Sunset at the equinox from the prehistoric site of Pizzo Vento at Fondachelli Fantina, Sicily (from History of astronomy)
Image 20The main platform at La Silla hosts a huge range of telescopes with which astronomers can explore the Universe. (from Observational astronomy)
Image 21One 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 22The Astronomer, 1668, by Johannes Vermeer (from Astronomer)
Image 23Historical accuracy of atomic clocks from NIST. (from Theoretical astronomy)
Image 24Places like Paranal Observatory offer crystal clear skies for observing astronomical objects with or without instruments. (from Amateur astronomy)
Image 25Hubble Space Telescope (from History of astronomy)
Image 26The Antikythera Mechanism was an analog computer from 150–100 BC designed to calculate the positions of astronomical objects. (from History of astronomy)
Image 279th-century diagram of the positions of the seven planets on 18 March 816, from the Leiden Aratea. (from History of astronomy)
Image 28Amateur astronomer recording observations of the sun. (from Amateur astronomy)
Image 29Segment of the astronomical ceiling of Senenmut's Tomb (circa 1479–1458 BCE), depicting constellations, protective deities, and twenty-four segmented wheels for the hours of the day and the months of the year. (from History of astronomy)
Image 30Southern Hemisphere (from History of astronomy)
Image 31Arabic astrolabe from 1079-80 AD (from History of astronomy)
Image 32Mayall telescope at Kitt Peak National Observatory (from Observational astronomy)
Image 33ALMA is the world's most powerful telescope for studying the Universe at submillimeter and millimeter wavelengths. (from Observational astronomy)

Refresh with new selections below (purge)

Featured article - show another

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

Portrait of Kepler by an unknown artist in 1620.

Johannes Kepler (/ˈkɛplər/; German: [joˈhanəs ˈkɛplɐ, -nɛs -] (listen); 27 December 1571 – 15 November 1630) was a German astronomer, mathematician, astrologer, natural philosopher and writer on music. He is a key figure in the 17th-century Scientific Revolution, best known for his laws of planetary motion, and his books Astronomia nova, Harmonice Mundi, and Epitome Astronomiae Copernicanae. These works also provided one of the foundations for Newton's theory of universal gravitation.

Kepler was a mathematics teacher at a seminary school in Graz, where he became an associate of Prince Hans Ulrich von Eggenberg. Later he became an assistant to the astronomer Tycho Brahe in Prague, and eventually the imperial mathematician to Emperor Rudolf II and his two successors Matthias and Ferdinand II. He also taught mathematics in Linz, and was an adviser to General Wallenstein.

Additionally, he did fundamental work in the field of optics, invented an improved version of the refracting (or Keplerian) telescope, and was mentioned in the telescopic discoveries of his contemporary Galileo Galilei. He was a corresponding member of the Accademia dei Lincei in Rome. (Full article...)

List of featured articles

edit

Did you know - show different entries

... that the asteroid 2011 XC2 missed the Earth by less than 1 lunar distance on 3 December 2011?
... that the mass-luminosity relation, first derived by Arthur Eddington in 1924, helps astronomers find the distances to binary star systems?
... that the planetary nebula Abell 39 is unusually spherical, yet its central star is offset from the center?
... that data from Mariner 10 led to the discovery of Mercury's magnetic field in 1974?
... that the Toronto Magnetic Observatory had to be moved as the University of Toronto's electric lighting was interfering with observations?

More Did you know facts

More Did you know (auto generated)

... that the producers of The Jet Propelled Couch hired "Miss Color TV", Vampira, and several Miss Americas to portray attractive creatures inhabiting an imaginary planet?
... that in 1948 and 1952, nuclear physicist Leslie Shepherd published scientific papers on the use of nuclear technology for interplanetary and interstellar space travel?
... that The City in the Middle of the Night, a 2019 climate-fiction novel by Charlie Jane Anders, is set on a tidally locked planet?
... that Nandivada Rathnasree, who ran Delhi's planetarium, proposed that astronomers could be taught using India's stone-built observatories?
... that it took five years of observations to find the planet orbiting the star HD 175167?
... that pushbacks of migrants in the Aegean Sea have been described as "a human rights violation that encapsulates a will to eliminate a person's presence on the face of the planet"?

edit

WikiProjects

WikiProject Astronomy	WikiProject Solar System



WikiProject Cosmology	WikiProject Spaceflight

edit

Selected image - show another

Credit: NASA / ESA / Hubble Heritage Team (STScI/AURA)

Messier 82, also known as NGC 3034, Cigar Galaxy, and M82, is the prototype starburst galaxy about 12 million light-years away in the constellation Ursa Major. The starburst galaxy is five times more luminous than the whole Milky Way, and one hundred times more luminous than our galaxy's center. This mosaic image, taken by the Hubble Space Telescope, is the sharpest wide-angle view ever obtained of Messier 82.

More selected pictures

Read more

edit

Astronomy News

9 August 2022 – Discoveries of exoplanets: Radio astronomers have discovered a newborn, Jupiter-size exoplanet orbiting the star AS 209, using the Atacama Large Millimeter Array telescope in Chile. (Space.com)
26 April 2022 –: In the morning, the Moon, Jupiter, and Venus are seen aligning with each other. (Space.com)
4 April 2022 – Discoveries of exoplanets: Astronomers announce the discovery of K2-2016-BLG-0005Lb, an exoplanet that is said to resemble Jupiter. The discovery was made using the now-retired Kepler space telescope. (ScienceAlert)
30 March 2022 –: The Hubble Space Telescope observes the most distant single star ever. The star, named Earendel by astronomers, is 28 billion light-years away. It is the farthest detection of a star, dating back 900 million years after the Big Bang. This discovery surpasses Hubble's record from 2018, when it discovered a star that existed when the universe was roughly four billion years old. (CNN)
21 March 2022 – Discoveries of exoplanets: NASA announces that they have discovered their 5000th exoplanet since 1992, when astronomers Aleksander Wolszczan and Dale Frail announced the discovery of two exoplanets orbiting PSR B1257+12. (Science News)

edit

August anniversaries

4 August 2007 – The Phoenix Mars Lander is launched from Cape Canaveral, carrying science instruments to analyze soil samples of the Martian northern polar region
6 August 2012 – The Mars rover Curiosity lands on the Red Planet as part of NASA's Mars Science Laboratory mission
7 August 1996 – Announcement of possible microfossils found in ALH84001 Martian Meteorite
20 August 1977 – Voyager 2 space probe is launched by NASA to study the outer planets and interstellar space beyond the Sun's heliosphere
21 August 2017 – NASA.gov conducts a broadcast of the total solar eclipse with more than 50 million views of the live broadcast, and almost 31 million unique views on Facebook before and after the eclipse
24 August 2006 – The International Astronomical Union votes to approve a new definition of "planet" that excludes Pluto
25 August 2003 – The Spitzer Space Telescope (SIRTF) is launched, dedicated to infrared astronomy
27 August 1962 – Mariner 2 launches on a journey to Venus, and is the first robotic space probe to conduct a successful planetary encounter
31 August 1913 – Bernard Lovell, a British physicist and radio astronomer is born