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29 relations: Angular diameter, Apparent magnitude, Astronomical spectroscopy, Birkhäuser, Bright Star Catalogue, Catalogues of Fundamental Stars, Constellation, Cyanogen, Dredge-up, Durchmusterung, Effective temperature, Giant star, Henry Draper Catalogue, Hipparcos, Hydra (constellation), Limb darkening, Metallicity, Minute and second of arc, Monthly Notices of the Royal Astronomical Society, Nuclear fusion, Parallax, Solar mass, Solar radius, Spectral line, Star, Stellar classification, Stellar evolution, Stellar rotation, Subgiant.
Angular diameter
The angular diameter, angular size, apparent diameter, or apparent size is an angular measurement describing how large a sphere or circle appears from a given point of view.
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Apparent magnitude
The apparent magnitude of a celestial object is a number that is a measure of its brightness as seen by an observer on Earth.
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Astronomical spectroscopy
Astronomical spectroscopy is the study of astronomy using the techniques of spectroscopy to measure the spectrum of electromagnetic radiation, including visible light and radio, which radiates from stars and other celestial objects.
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Birkhäuser
Birkhäuser is a former Swiss publisher founded in 1879 by Emil Birkhäuser.
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Bright Star Catalogue
The Bright Star Catalogue, also known as the Yale Catalogue of Bright Stars or Yale Bright Star Catalogue, is a star catalogue that lists all stars of stellar magnitude 6.5 or brighter, which is roughly every star visible to the naked eye from Earth.
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Catalogues of Fundamental Stars
The Catalogue of Fundamental Stars is a series of six astrometric catalogues of high precision positional data for a small selection of stars to define a celestial reference frame, which is a standard coordinate system for measuring positions of stars.
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Constellation
A constellation is a group of stars that are considered to form imaginary outlines or meaningful patterns on the celestial sphere, typically representing animals, mythological people or gods, mythological creatures, or manufactured devices.
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Cyanogen
Cyanogen is the chemical compound with the formula (CN)2.
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Dredge-up
A dredge-up is a period in the evolution of a star where a surface convection zone extends down to the layers where material has undergone nuclear fusion.
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Durchmusterung
In astronomy, Durchmusterung or Bonner Durchmusterung (BD), is the comprehensive astrometric star catalogue of the whole sky, compiled by the Bonn Observatory (Germany) from 1859 to 1903.
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Effective temperature
The effective temperature of a body such as a star or planet is the temperature of a black body that would emit the same total amount of electromagnetic radiation.
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Giant star
A giant star is a star with substantially larger radius and luminosity than a main-sequence (or dwarf) star of the same surface temperature.
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Henry Draper Catalogue
The Henry Draper Catalogue (HD) is an astronomical star catalogue published between 1918 and 1924, giving spectroscopic classifications for 225,300 stars; it was later expanded by the Henry Draper Extension (HDE), published between 1925 and 1936, which gave classifications for 46,850 more stars, and by the Henry Draper Extension Charts (HDEC), published from 1937 to 1949 in the form of charts, which gave classifications for 86,933 more stars.
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Hipparcos
Hipparcos was a scientific satellite of the European Space Agency (ESA), launched in 1989 and operated until 1993.
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Hydra (constellation)
Hydra is the largest of the 88 modern constellations, measuring 1303 square degrees.
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Limb darkening
Limb darkening is an optical effect seen in stars (including the Sun), where the center part of the disk appears brighter than the edge or limb of the image.
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Metallicity
In astronomy, metallicity is used to describe the abundance of elements present in an object that are heavier than hydrogen or helium.
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Minute and second of arc
A minute of arc, arcminute (arcmin), arc minute, or minute arc is a unit of angular measurement equal to of one degree.
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Monthly Notices of the Royal Astronomical Society
Monthly Notices of the Royal Astronomical Society (MNRAS) is a peer-reviewed scientific journal covering research in astronomy and astrophysics.
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Nuclear fusion
In nuclear physics, nuclear fusion is a reaction in which two or more atomic nuclei come close enough to form one or more different atomic nuclei and subatomic particles (neutrons or protons).
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Parallax
Parallax is a displacement or difference in the apparent position of an object viewed along two different lines of sight, and is measured by the angle or semi-angle of inclination between those two lines.
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Solar mass
The solar mass is a standard unit of mass in astronomy, equal to approximately.
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Solar radius
Solar radius is a unit of distance used to express the size of stars in astronomy.
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Spectral line
A spectral line is a dark or bright line in an otherwise uniform and continuous spectrum, resulting from emission or absorption of light in a narrow frequency range, compared with the nearby frequencies.
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Star
A star is type of astronomical object consisting of a luminous spheroid of plasma held together by its own gravity.
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Stellar classification
In astronomy, stellar classification is the classification of stars based on their spectral characteristics.
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Stellar evolution
Stellar evolution is the process by which a star changes over the course of time.
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Stellar rotation
Stellar rotation is the angular motion of a star about its axis.
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Subgiant
A subgiant is a star that is brighter than a normal main-sequence star of the same spectral class, but not as bright as true giant stars.
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References
[1] https://en.wikipedia.org/wiki/Pi_Hydrae
