Amateur astronomy is a hobby where participants enjoy observing or imaging celestial objects in the sky using the unaided eye, binoculars, or telescopes. Even though scientific research may not be their primary goal, some amateur astronomers make contributions in doing citizen science, such as by monitoring variable stars, double stars, sunspots, or occultations of stars by the Moon or asteroids, or by discovering transient astronomical events, such as comets, galactic novae or supernovae in other galaxies.
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.
Flexible Image Transport System (FITS) is an open standard defining a digital file format useful for storage, transmission and processing of data: formatted as multi-dimensional arrays, or tables. FITS is the most commonly used digital file format in astronomy. The FITS standard was designed specifically for astronomical data, and includes provisions such as describing photometric and spatial calibration information, together with image origin metadata.
The SAO/NASA Astrophysics Data System (ADS) is an online database of over 16 million papers developed by the National Aeronautics and Space Administration (NASA) on astronomy and physics. Abstracts are freely available for most articles, and fully scanned articles may be available in Graphics Interchange Format (GIF) and Portable Document Format (PDF). Hosted papers may be from peer reviewed and/or non-peer-reviewed sources. ADS is managed by the Smithsonian Astrophysical Observatory.
IRAF is a collection of software written at the National Optical Astronomy Observatory (NOAO) geared towards the reduction of astronomical images and spectra in pixel array form. This is primarily data taken from imaging array detectors such as CCDs. It is available for all major operating systems for mainframes and desktop computers. IRAF was designed cross-platform, supporting VMS and UNIX-like operating systems. Use on Microsoft Windows was made possible by Cygwin in earlier versions, and can be today done with the Windows Subsystem for Linux. Today, it is primarily used on macOS and Linux.
Leiden Observatory is an astronomical institute of Leiden University, in the Netherlands. Established in 1633 to house the quadrant of Rudolph Snellius, it is the oldest operating university observatory in the world, with the only older still existing observatory being the Vatican Observatory.
The Digitized Sky Survey (DSS) is a digitized version of several photographic astronomical surveys of the night sky, produced by the Space Telescope Science Institute between 1983 and 2006.
The Center for Astrophysics | Harvard & Smithsonian (CfA), previously known as the Harvard–Smithsonian Center for Astrophysics, is an astrophysics research institute jointly operated by the Harvard College Observatory and Smithsonian Astrophysical Observatory. Founded in 1973 and headquartered in Cambridge, Massachusetts, United States, the CfA leads a broad program of research in astronomy, astrophysics, Earth and space sciences, as well as science education. The CfA either leads or participates in the development and operations of more than fifteen ground- and space-based astronomical research observatories across the electromagnetic spectrum, including the forthcoming Giant Magellan Telescope (GMT) and the Chandra X-ray Observatory, one of NASA's Great Observatories.
The Starlink Project, referred to by users as Starlink and by developers as simply The Project, was a UK astronomical computing project which supplied general-purpose data reduction software. Until the late 1990s, it also supplied computing hardware and system administration personnel to UK astronomical institutes. In the former respect, it was analogous to the US IRAF project.
Paolo Padovani is an Italian astronomer working at the European Southern Observatory, specializing in the study of Active galactic nuclei including the study of quasars and blazars, evolution and multifrequency studies and extragalactic backgrounds. In 2004 he and several other astronomers discovered 30 supermassive blackholes at the European Astrophysical Virtual Observatory using pioneering techniques.
ELODIE was an echelle spectrograph installed on the 1.93m reflector at the Observatoire de Haute-Provence in south-eastern France. Its optical instrumentation was developed by André Baranne from the Marseille Observatory. The purpose of the instrument was extrasolar planet detection by the radial velocity method.
The International Virtual Observatory Alliance (IVOA) is a worldwide scientific organisation formed in June 2002. Its mission is to facilitate international coordination and collaboration necessary for enabling global and integrated access to data gathered by astronomical observatories. An information system allowing such an access is called a virtual observatory. The main task of the organisation so far has focused on defining standards to ensure interoperability of the different virtual observatory projects already existing or in development.
The Centre de Données astronomiques de Strasbourg is a data centre which collects and distributes astronomical information . It was established in 1972 under the name Centre de Données Stellaires by the National Institute of Astronomy and Geophysics (INAG). The on-line services currently provided by the CDS include:
The VizieR Catalogue Service is an astronomical catalog service provided by Centre de données astronomiques de Strasbourg. The origin of the service dates back to 1993, when it was founded by the European Space Agency as the European Space Information System (ESIS) Catalogue Browser. Initially intended to serve the space science community, the ESIS project pre-dates the World Wide Web as a network database allowing uniform to a heterogeneous set of catalogues and data.
Astroinformatics is an interdisciplinary field of study involving the combination of astronomy, data science, machine learning, informatics, and information/communications technologies. The field is closely related to astrostatistics.
Astronomy Visualization Metadata (AVM) is a standard for tagging digital astronomical images stored in formats such as JPEG, GIF, PNG and TIFF. The AVM standard extends the concept of Extensible Metadata Platform (XMP) headers to include useful astronomical information about the subject of the image as well as the telescope used to take the image. This ensures that relevant information is transferred with the image when it is shared with others. AVM could be considered analogous to the FITS headers associated with raw astronomical data files.
Time-domain astronomy is the study of how astronomical objects change with time. Though the study may be said to begin with Galileo's Letters on Sunspots, the term now refers especially to variable objects beyond the Solar System. Changes over time may be due to movements or changes in the object itself. Common targets included are supernovae, pulsating stars, novas, flare stars, blazars and active galactic nuclei. Visible light time domain studies include OGLE, HAT-South, PanSTARRS, SkyMapper, ASAS, WASP, CRTS, and in a near future the LSST at the Vera C. Rubin Observatory.
Astropy is a collection of software packages written in the Python programming language and designed for use in astronomy. The software is a single, free, core package for astronomical utilities due to the increasingly widespread usage of Python by astronomers, and to foster interoperability between various extant Python astronomy packages. Astropy is included in several large Python distributions; it is part of package managers for Linux and macOS, the Anaconda Python Distribution, Enthought Canopy and Ureka.
Aperture Photometry Tool (APT) is software with a graphical user interface for computing aperture photometry on astronomical imagery. Image overlays, graphical representations, statistics, models, options and controls for aperture-photometry calculations are brought together into a single package. The software also can be used as a FITS-image viewer. APT is executed on desktop and laptop computers, and is free of charge under a license that limits its use to astronomical research and education. The software may be downloaded from its official website, and requires the Java Virtual Machine to be installed on the user's computer.
Astronomical Data Query Language (ADQL) is a language for astronomical data query based on SQL 92.
