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The UBV Photoelectric Photometry Catalogue, or UBV M, is the star brightness catalogue that complies to the UBV photometric system developed by astronomer Harold Johnson. Evolution of the UBV Photoelectric Photometry Catalogue
Apparent magnitude (m) is a measure of the brightness of a star, astronomical object or other celestial objects like artificial satellites. Its value depends on its intrinsic luminosity , its distance, and any extinction of the object's light caused by interstellar dust along the line of sight to the observer.
The Strömgren photometric system, abbreviated also as uvbyβ or simply uvby, and sometimes referred as Strömgren - Crawford photometric system, is a four-colour medium-passband photometric system plus Hβ (H-beta) filters for determining magnitudes and obtaining spectral classification of stars.
The Bortle dark-sky scale (usually referred to as simply the Bortle scale) is a nine-level numeric scale that measures the night sky's brightness of a particular location. It quantifies the astronomical observability of celestial objects and the interference caused by light pollution .
A number of free computer programs are available for synthetic aperture photometry and PSF-fitting photometry. SExtractor [37] and Aperture Photometry Tool [38] are popular examples for aperture photometry. The former is geared towards reduction of large scale galaxy-survey data, and the latter has a graphical user interface (GUI) suitable for ...
Sky Quality Meter model SQM-L. A sky quality meter (SQM) is an instrument used to measure the luminance of the night sky, more specifically the Night Sky Brightness (NSB) at the zenith, with a bandwidth ranging from 390 nm to 600 nm. [1]
when either the occulting or occulted body are double, e.g. a double star or double asteroid, then a step light curve is observed. when the occulted body is large, e.g. a star like Antares, then the transitions are gradual. when the occulting body has an atmosphere, e.g. the moon Titan [8]
The bolometric correction scale is set by the absolute magnitude of the Sun and an adopted (arbitrary) absolute bolometric magnitude for the Sun.Hence, while the absolute magnitude of the Sun in different filters is a physical and not arbitrary quantity, the absolute bolometric magnitude of the Sun is arbitrary, and so the zero-point of the bolometric correction scale that follows from it.