Portal:Astronomy

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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 1Map 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 2One 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 3Babylonian tablet in the British Museum recording Halley's comet in 164 BC (from History of astronomy)
Image 4Sunset at the equinox from the prehistoric site of Pizzo Vento at Fondachelli Fantina, Sicily (from History of astronomy)
Image 5An amateur astrophotography setup with an automated guide system connected to a laptop. (from Observational astronomy)
Image 69th-century diagram of the positions of the seven planets on 18 March 816, from the Leiden Aratea (from History of astronomy)
Image 7The Astronomer, 1668, by Johannes Vermeer (from Astronomer)
Image 8An 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 9The Crab Nebula as seen in various wavelengths (from Observational astronomy)
Image 10Historical Jantar Mantar observatory in Jaipur, India (from History of astronomy)
Image 11An assembly in Estonia to observe meteors (from Observational astronomy)
Image 12Mayall telescope at Kitt Peak National Observatory (from Observational astronomy)
Image 13Hubble Space Telescope (from History of astronomy)
Image 14Historical accuracy of atomic clocks from NIST. (from Theoretical astronomy)
Image 15Segment 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 16Ultra HD photography taken at La Silla Observatory. (from Observational astronomy)
Image 17Amateur astronomer recording observations of the sun. (from Amateur astronomy)
Image 18The Antikythera Mechanism was an analog computer from 150–100 BC designed to calculate the positions of astronomical objects. (from History of astronomy)
Image 19Places like Paranal Observatory offer crystal clear skies for observing astronomical objects with or without instruments. (from Amateur astronomy)
Image 20ALMA is the world's most powerful telescope for studying the Universe at submillimeter and millimeter wavelengths. (from Observational astronomy)
Image 21Comparison of CMB (Cosmic microwave background) results from satellites COBE, WMAP and Planck documenting a progress in 1989–2013 (from History of astronomy)
Image 22Sir Patrick Moore was one of the world's leading popularisers of astronomy. (from Amateur astronomy)
Image 23The Nebra sky disk, Germany, 1800 - 1600 BC (from History of astronomy)
$Image 2450 cm refracting telescope at Nice Observatory. (from Observational astronomy)$

Image 2450 cm refracting telescope at Nice Observatory. (from Observational astronomy)
Image 25Portrait 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 26Calendrical functions of the Berlin Gold Hat c. 1000 BC (from History of astronomy)
Image 27Southern Hemisphere (from History of astronomy)
Image 28Arabic astrolabe from 1079-80 AD (from History of astronomy)
Image 29One of the rolls of amateur astronomy groups is outreach programs bringing astronomy to the general public (from Amateur astronomy)
Image 30The main platform at La Silla hosts a huge range of telescopes with which astronomers can explore the Universe. (from Observational astronomy)
Image 31History 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 32"El Caracol" observatory temple at Chichen Itza, Mexico (from History of astronomy)
Image 33The 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)

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

Herbig–Haro (HH) objects are bright patches of nebulosity associated with newborn stars. They are formed when narrow jets of partially ionised gas ejected by stars collide with nearby clouds of gas and dust at several hundred kilometres per second. Herbig–Haro objects are commonly found in star-forming regions, and several are often seen around a single star, aligned with its rotational axis. Most of them lie within about one parsec (3.26 light-years) of the source, although some have been observed several parsecs away. HH objects are transient phenomena that last around a few tens of thousands of years. They can change visibly over timescales of a few years as they move rapidly away from their parent star into the gas clouds of interstellar space (the interstellar medium or ISM). Hubble Space Telescope observations have revealed the complex evolution of HH objects over the period of a few years, as parts of the nebula fade while others brighten as they collide with the clumpy material of the interstellar medium.

First observed in the late 19th century by Sherburne Wesley Burnham, Herbig–Haro objects were recognised as a distinct type of emission nebula in the 1940s. The first astronomers to study them in detail were George Herbig and Guillermo Haro, after whom they have been named. Herbig and Haro were working independently on studies of star formation when they first analysed the objects, and recognised that they were a by-product of the star formation process. Although HH objects are a visible wavelength phenomena, many remain invisible at these wavelengths due to dust and gas, and can only be detected at infrared wavelengths. Such objects, when observed in near infrared, are called molecular hydrogen emission-line objects (MHOs). (Full article...)

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... that Caroline Moore was 14 years old when she discovered supernova 2008ha?
... that although Charles Messier discovered the galaxy M91 in 1781, it was added to his catalogue only two centuries later?
... that Beta Cassiopeiae is the brightest of the Delta Scuti variables in the sky?
... that the fall of the Neuschwanstein meteorite in 2002 was observed by the European Fireball Network and outdoor witnesses through most of Central Europe?
... that AG Pegasi has been described as the slowest nova ever recorded?

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... that by naming her album Planet Her, Doja Cat was "just trying to be cute" and was not promoting a feminist agenda nor a planet exclusively for women?
... 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 Mariner 1, the United States' first interplanetary probe, was lost in 1962 due to the miscoding of a single character in its software?
... 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 Nandivada Rathnasree, who ran Delhi's planetarium, proposed that astronomers could be taught using India's stone-built observatories?
... that NGC 4848, a spiral galaxy, lost most of its hydrogen gas as it passed through the Coma Cluster due to ram pressure?

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WikiProjects

WikiProject Astronomy	WikiProject Solar System



WikiProject Cosmology	WikiProject Spaceflight

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Credit: Michael S Adler

A total solar eclipse during totality, seen from outside Crowheart, Wyoming on 21 August, 2017. At this point during the solar eclipse, the photograph shows both the Sun's corona and the surface features of the new moon itself, illuminated by earthshine.

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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)

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September anniversaries

5 September 1977 – Space probe Voyager 1 is launched on a mission to study Jupiter and Saturn
8 September 1966 – The first episode of a new television science fiction series "Star Trek" is shown on NBC-TV
12 September 2013 – NASA announces that 19 days earlier, Voyager 1 had become the first man-made object to cross the heliopause and enter interstellar space
15 September 2017 – The Cassini spacecraft plunges into the atmosphere of Saturn, ending its 13-year tour of the ringed planet
21 September 1866 – Science fiction writer, H. G. (Herbert George) Wells is born, in England
23 September 1846 – The planet Neptune is discovered by Johann Gottfried Galle using mathematical equations from John Couch Adams and Urbain Le Verrier
29 September 1971 – The Orbiting Solar Observatory 7 satellite launches with the first x-ray observations of a beginning solar flare and of solar streamers

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Space-related Portals

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Astronomical events

All times UT unless otherwise specified.

7 September, 18:17	Moon at perigee
10 September, 09:59	Full moon
14 September, 22:59	Moon occults Uranus
16 September, 21:03	Neptune at opposition
19 September, 14:44	Moon at apogee
23 September, 01:04	Earth southward equinox
23 September, 06:47	Mercury at inferior conjunction
25 September, 21:54	New moon
26 September, 18:03	Jupiter at opposition