Outline 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 natural science – one that seeks to elucidate the rules that govern the natural world using empirical and scientific methods.
    • A branch or field of space science
• A hobby or part-time pursuit for the satisfaction of personal curiosity or appreciation of beauty, the latter especially including astrophotography.

• 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] 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.
  • 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.
  • Atmospheric science – study of atmospheres and weather.
  • Exoplanetology – various planets outside of the Solar System
  • Planetary formation – formation of planets and moons in the context of the formation and evolution of the Solar System.
  • Planetary rings – dynamics, stability, and composition of planetary rings
  • Magnetospheres – magnetic fields of planets and moons
  • Planetary surfaces – surface geology of planets and moons
  • Planetary interiors – interior composition of planets and moons
  • Small Solar System bodies – smallest gravitationally bound bodies, including asteroids, comets, and Kuiper belt objects.
• 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:
    • Radio astronomy – Above 300 µm
    • Submillimetre astronomy – 200 µm to 1 mm
    • Infrared astronomy – 0.7–350 µm
    • Optical astronomy – 380–750 nm
    • Ultraviolet astronomy – 10–320 nm
    • X-ray astronomy – 0.01–10 nm
    • Gamma-ray astronomy – Below 0.01 nm
    • Cosmic ray astronomy – Cosmic rays, including plasma
    • Neutrino astronomy – Neutrinos
    • Gravitational wave astronomy – Gravitons
  • Photometry – study of how bright celestial objects are when passed through different filters
  • Spectroscopy – study of the spectra of astronomical objects
• Other disciplines that may be considered part of astronomy:
  • Archaeoastronomy
  • Astrochemistry

Astronomical object

Black holes

Artist's representation of a black hole.

Black hole

• Types
  • Schwarzschild metric
  • Rotating black hole
  • Charged black hole
  • Virtual black hole
• Size
  • Micro black hole
  • Extremal black hole (Black hole electron)
  • Stellar black hole
  • Intermediate-mass black hole
  • Supermassive black hole
  • Quasar
    • Active galactic nucleus
    • Blazar
• Formation
  • Stellar evolution
  • Gravitational collapse
  • Neutron star (Template:neutron star)
  • Compact star
    • Quark star
    • Exotic star
  • Tolman–Oppenheimer–Volkoff limit
  • White dwarf (Template:white dwarf)
  • Supernova (Template:supernovae)
  • Hypernova
  • Gamma-ray burst
• Properties
  • Black hole thermodynamics
  • Schwarzschild radius
  • M-sigma relation
  • Event horizon
  • Quasi-periodic oscillation
  • Photon sphere
  • Ergosphere
  • Hawking radiation
  • Penrose process
  • Bondi accretion
  • Spaghettification
  • Gravitational lens
• Models
  • Gravitational singularity (Penrose–Hawking singularity theorems)
  • Primordial black hole
  • Gravastar
  • Dark star
  • Dark energy star
  • Black star
  • Magnetospheric eternally collapsing object
  • Fuzzball
  • White hole
  • Naked singularity
  • Ring singularity
  • Immirzi parameter
  • Membrane paradigm
  • Kugelblitz
  • Wormhole
  • Quasistar
• Issues
  • No-hair theorem
  • Black hole information paradox
  • Cosmic censorship hypothesis
  • Nonsingular black hole models
  • Holographic principle
  • Black hole complementarity
• Metrics
  • Schwarzschild metric
  • Kerr metric
  • Reissner–Nordström
  • Kerr–Newman
• Related
  • List of black holes
  • Timeline of black hole physics
  • Rossi X-ray Timing Explorer
  • Hypercompact stellar system

• 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