Portal:Astronomy

The Astronomy Portal

Introduction

Astronomy is a natural science that studies celestial objects and the phenomena that occur in the cosmos. It uses mathematics, physics, and chemistry in order to explain their origin and their overall evolution. Objects of interest include planets, moons, stars, nebulae, galaxies, meteoroids, asteroids, 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 Egyptians, Babylonians, Greeks, Indians, 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.

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 1Overview of types of observational astronomy by observed wavelengths and their observability. (from Observational astronomy)
Image 2Babylonian tablet in the British Museum recording Halley's Comet in 164 BC (from History of astronomy)
Image 3Southern Hemisphere (from History of astronomy)
Image 4Map 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 5The Hubble Space Telescope (from History of astronomy)
$Image 650 cm refracting telescope at Nice Observatory (from Observational astronomy)$

Image 650 cm refracting telescope at Nice Observatory (from Observational astronomy)
Image 7One 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 8Amateur astronomer recording observations of the sun. (from Amateur astronomy)
Image 9The Nebra sky disk, Germany, 1800–1600 BC (from History of astronomy)
Image 10Ultra HD photography taken at La Silla Observatory (from Observational astronomy)
Image 11An amateur astrophotography setup with an automated guide system connected to a laptop (from Observational astronomy)
Image 12The 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 13The inflationary theory as an augmentation to the Big Bang theory was first proposed by Alan Guth of MIT. Inflation solves the 'horizon problem' by making the early universe much more compact than was assumed in the standard model. Given such smaller size, causal contact (i.e., thermal communication) would have been possible among all regions of the early universe. The image was an adaptation from various generic charts depicting the growth of the size of the observable universe, for both the standard model and inflationary model respectively, of the Big Bang theory. (from Physical cosmology)
Image 14Mayall telescope at Kitt Peak National Observatory (from Observational astronomy)
Image 15Calendrical functions of the Berlin Gold Hat c. 1000 BC (from History of astronomy)
Image 16Arabic astrolabe from 1079 to 1080 AD (from History of astronomy)
Image 17An assembly in Estonia to observe meteors (from Observational astronomy)
Image 18A voting session is conducted in 2006 International Astronomical Union's general assembly for determining a new definition of a planet (from Astronomer)
Image 19Artist conception of the Big Bang cosmological model, the most widely accepted out of all in physical cosmology (neither time nor size to scale) (from Physical cosmology)
Image 20An example of a gravitational lens found in the DESI Legacy Surveys data. There are four sets of lensed images in DESI-090.9854-35.9683, corresponding to four distinct background galaxies—from the outermost giant red arc to the innermost bright blue arc, arranged in four concentric circles. All of them are gravitationally warped—or lensed—by the orange galaxy at the very center. Dark matter is expected to produce gravitational lensing also. (from Physical cosmology)
Image 21The Crab Nebula as seen in various wavelengths (from Observational astronomy)
Image 22An 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 23Sunset at the equinox from the prehistoric site of Pizzo Vento at Fondachelli Fantina, Sicily (from History of astronomy)
Image 24Comparison of CMB (Cosmic microwave background) results from satellites COBE, WMAP and Planck documenting a progress in 1989–2013 (from History of astronomy)
Image 25Historical accuracy of atomic clocks from NIST. (from Theoretical astronomy)
Image 26Sir Patrick Moore was one of the world's leading popularisers of astronomy. (from Amateur astronomy)
Image 27The main platform at La Silla hosts a huge range of telescopes with which astronomers can explore the Universe. (from Observational astronomy)
Image 28Portrait 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 29Historical Jantar Mantar observatory in Jaipur, India (from History of astronomy)
Image 30History of the Universe – gravitational waves are hypothesized to arise from cosmic inflation, a rapidly accelerated expansion just after the Big Bang (from Physical cosmology)
Image 319th-century diagram of the positions of the seven planets on 18 March 816, from the Leiden Aratea (from History of astronomy)
Image 32Places like Paranal Observatory offer crystal clear skies for observing astronomical objects with or without instruments. (from Amateur astronomy)
Image 33Segment of the astronomical ceiling of Senenmut's Tomb (circa 1479–1458 BC), 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 34The Oort cloud, one of the most successful theoretical models about the Solar System (from Theoretical astronomy)
Image 35"El Caracol" observatory temple at Chichen Itza, Mexico (from History of astronomy)
Image 36ALMA is the world's most powerful telescope for studying the Universe at submillimeter and millimeter wavelengths. (from Observational astronomy)
Image 37Amateur astronomy groups are often involved in outreach to introduce astronomy to the general public (from Amateur 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 by August Köhler, c. 1910, after 1620 original

Johannes Kepler (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, influencing among others Isaac Newton, providing one of the foundations for his theory of universal gravitation. The variety and impact of his work made Kepler one of the founders and fathers of modern astronomy, the scientific method, natural and modern science. He has been described as the "father of science fiction" for his novel Somnium.

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, being named the father of modern optics, in particular for his Astronomiae pars optica. He also invented an improved version of the refracting telescope, the Keplerian telescope, which became the foundation of the modern refracting telescope, while also improving on the telescope design by Galileo Galilei, who mentioned Kepler's discoveries in his work. He is also known for postulating the Kepler conjecture. (Full article...)

List of featured articles

edit

Did you know - show different entries

... that light echoes appear to exceed the speed of light due to simple interstellar illusions?
... that the Leo IV dwarf galaxy is one of the smallest satellites of the Milky Way?
... that a hydrocarbon lake on Saturn's moon Titan and an active volcano on Jupiter's moon Io are among the Solar System features named after deities from Māori mythology?
... that the Local Void is an empty region of space, devoid of matter, lying adjacent to our own Milky Way galaxy?
... that William Herschel's 40-foot telescope was the largest telescope in the world for 50 years?

More Did you know facts

More Did you know (auto generated)

... that examples of artificial planets in science fiction include Riverworld, the Well World, and the Death Star?
... that the Passive Seismic Experiment Package recorded one of the first instances of humans littering on another planetary body?
... that novelist Hal Clement created the planet Mesklin in 1953 based on the real-world suspected detection of an extrasolar planet?
... that a group of K-pop fans performed a dance with the goal of convincing a company to commit to 100% renewable energy?
... that in many works of fiction, the asteroid belt is the remnants of a destroyed planet?
... that King Gizzard & the Lizard Wizard's "cli-fi" thrash metal album addresses a mix of current ecological threats and attempts to find another planet to live on?

edit

WikiProjects

WikiProject Astronomy	WikiProject Solar System



WikiProject Cosmology	WikiProject Spaceflight

edit

Selected image - show another

Credit: NASA

Coronal loops are huge loops of magnetic field beginning and ending on the Sun's visible surface (photosphere) projecting into the solar atmosphere (corona). Image of typical coronal loops observed by TRACE.

More selected pictures

Read more

edit

Astronomy News

No recent news

edit

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 1996 – 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)

More anniversaries

edit

Space-related Portals

edit

Astronomical events

All times UT unless otherwise specified.

1 June, 01:59	Venus at greatest western elongation
7 June, 10:42	Moon at apogee
11 June, 07:44	Full moon
21 June, 02:42	Earth northern solstice
23 June, 04:43	Moon at perigee
24 June, 15:06	Jupiter at conjunction; occultation
25 June, 10:31	New moon
30 June, 01:05	Moon occults Mars