Overview of the scientific field of astronomy
Mauna Kea in Hawaii is one of the world's premier observatory sites. Pictured is the W. M. Keck Observatory , an optical interferometer .The following outline is provided as an overview of and topical guide to astronomy:
Astronomy – studies the universe beyond Earth, including its formation and development , and the evolution, physics , chemistry , meteorology , and motion of celestial objects (such as galaxies , planets , etc.) and phenomena that originate outside the atmosphere of Earth (such as the cosmic background radiation ). Astronomy also intersects with biology, as astrobiology , studying potential life throughout the universe.
Nature of astronomy Astronomy can be described as all the following:
An academic discipline : one with academic departments, curricula and degrees; national and international societies; and specialized journals. A scientific field (a branch of science ) – widely recognized category of specialized expertise within science, and typically embodies it A hobby or part-time pursuit for the satisfaction of personal curiosity or appreciation of beauty , the latter especially including astrophotography .
Branches of astronomy Astrobiology – studies the advent and evolution of biological systems in the universe.Astrophysics – branch of astronomy that deals with the physics of the universe, including the physical properties of celestial objects, as well as their interactions and behavior.[1] [2] Among the objects studied are galaxies, stars , planets, exoplanets , the interstellar medium and the cosmic microwave background ; and the properties examined include luminosity , density , temperature , and chemical composition. The subdisciplines of theoretical astrophysics are:Compact objects – this subdiscipline studies very dense matter in white dwarfs and neutron stars and their effects on environments including accretion .Physical cosmology – origin and evolution of the universe as a whole. The study of cosmology is theoretical astrophysics at its largest scale.Quantum cosmology - the study of cosmology through the use of quantum field theory to explain phenomena general relativity cannot due to limitations in its framework.Computational astrophysics – The study of astrophysics using computational methods and tools to develop computational models.Galactic astronomy – deals with the structure and components of our Galaxy and of other galaxies.High energy astrophysics – studies phenomena occurring at high energies including active galactic nuclei , supernovae , gamma-ray bursts , quasars , and shocks . Interstellar astrophysics – study of the interstellar medium , intergalactic medium and dust. Extragalactic astronomy – study of objects (mainly galaxies) outside our Galaxy, including galaxy formation and evolution .Stellar astronomy – concerned with Star formation , physical properties, main sequence life span, variability , stellar evolution and extinction.Plasma astrophysics – studies properties of plasma in outer space.Relativistic astrophysics – studies effects of special relativity and general relativity in astrophysical contexts including gravitational waves , gravitational lensing and black holes .Solar physics – Sun and its interaction with the remainder of the Solar System and interstellar space.Planetary Science – study of planets, moons, and planetary systems.Astronomy divided by general technique used for astronomical research:Astrometry – study of the position of objects in the sky and their changes of position. Defines the system of coordinates used and the kinematics of objects in our Galaxy.Observational astronomy – practice of observing celestial objects by using telescopes and other astronomical apparatus. It is concerned with recording data. The subdisciplines of observational astronomy are generally made by the specifications of the detectors, specifically the ranges of wavelengths observed:Photometry – study of how bright celestial objects are when passed through different filtersSpectroscopy – study of the spectra of astronomical objects Other disciplines that may be considered part of astronomy:
History of astronomy
Basic astronomical phenomena
Astronomical objects Astronomical object
Solar System
Sun
Planets
Small Solar System bodies
Exoplanets Exoplanet (also known as extrasolar planets) – planet outside the Solar System. A total of 4,341 such planets have been identified as of 28 Jan 2021.Super-Earth – exoplanet with a mass higher than Earth's, but substantially below those of the Solar System's ice giants .Mini-Neptune – also known as a gas dwarf or transitional planet. A planet up to 10 Earth masses, but less massive than Uranus and Neptune.Super-Jupiter – an exoplanet more massive than Jupiter .Sub-Earth – an exoplanet "substantially less massive" than Earth and Venus .Circumbinary planet – an exoplanet that orbits two stars.Hot Jupiter – an exoplanet whose characteristics are similar to Jupiter, but that have high surface temperatures because they orbit very close to their parent stars, whereas Jupiter orbits its parent star (the Sun) at 5.2 AU (780×106 km), causing low surface temperatures.Hot Neptune – an exoplanet in an orbit close to its star (normally less than one astronomical unit away), with a mass similar to that of Uranus or Neptune.Pulsar planet – a planet that orbits a pulsar or a rapidly rotating neutron star.Rogue planet (also known as an interstellar planet) – a planetary-mass object that orbits the galaxy directly.
Stars and stellar objects
Stars
Variable stars
Supernovae Supernova
Classes Related Structure Progenitors Remnants Discovery Notable Research
Black holes Artist's representation of a black hole. Black hole
Types Size Formation Properties Models Issues Metrics Related
Constellations
The 88 modern constellations
Constellation history The 48 constellations listed by Ptolemy after 150 AD
The 41 additional constellations added in the 16th and 17th centuries
Obsolete constellations including Ptolemy's Argo Navis
Clusters and nebulae
Galaxies
Cosmology
Space exploration See: Outline of space exploration
Organizations
Public sector space agencies Space agencies
Africa
North Africa
Sub-Saharan
North America
South America
Asia
East Asia
Southeast Asia
South Asia
Southwest Asia
Central Asia
Europe
Oceania
World 1 Preceded by the Soviet space program
Books and publications
Astronomers
See also
References ^ "astrophysics". Merriam-Webster, Incorporated. Retrieved 2011-05-22 . ^ "Stern kaufen". Retrieved 15 September 2012 .
External links Astronomy Guide For reviews on astronomy products, how-to's and current events. Astronomy Net Resources, forums (from 1995), articles on Astronomy. International Year of Astronomy 2009 IYA2009 Main website Cosmic Journey: A History of Scientific Cosmology from the American Institute of Physics Astronomy Picture of the Day Southern Hemisphere Astronomy Sky & Telescope publishers Astronomy Magazine Latest astronomy news in 11 languages Universe Today for astronomy and space-related news Celestia Motherlode Educational site for Astronomical journeys through space Search Engine for Astronomy Hubblesite.org – home of NASA's Hubble Space Telescope Astronomy – A History – G. Forbes – 1909 (eLibrary Project – eLib Text) (historical) Prof. Sir Harry Kroto, NL, Astrophysical Chemistry Lecture Series. 8 Freeview Lectures provided by the Vega Science Trust. Core books and core journals in Astronomy, from the Smithsonian/NASA Astrophysics Data System