57 relations: A-type main-sequence star, Algol, B(e) star, Balmer series, Beta Scorpii, Blue giant, Blue supergiant star, Bright Star Catalogue, Cambridge University Press, Chemically peculiar star, CNO cycle, Convection zone, Corona, Effective temperature, Electromagnetic radiation, Eta Aurigae, Eta Ursae Majoris, Forbidden mechanism, Helium, Herbig Ae/Be star, HIP 78530 b, Hydrogen, Hydrogen spectral series, Ionization, Kappa Andromedae b, Kelvin, Main sequence, Omega Fornacis, Omega Scorpii, Perturbation theory (quantum mechanics), Princeton University Press, Publications of the Astronomical Society of the Pacific, Quantum mechanics, Regulus, Rho Aurigae, SIMBAD, Solar mass, Solar radius, Spectral line, Star, Star count, Stellar classification, Stellar mass, Stellar rotation, Stellar wind, Subdwarf B star, Subgiant, Sun, Supergiant star, Surface gravity, ..., Tau Scorpii, Thermonuclear fusion, Upsilon Orionis, 18 Tauri, 22 Scorpii, 29 Persei, 42 Orionis. Expand index (7 more) » « Shrink index
An A-type main-sequence star (A V) or A dwarf star is a main-sequence (hydrogen-burning) star of spectral type A and luminosity class V. These stars have spectra which are defined by strong hydrogen Balmer absorption lines.
Algol, designated Beta Persei (β Persei, abbreviated Beta Per, β Per), known colloquially as the Demon Star, is a bright multiple star in the constellation of Perseus and one of the first non-nova variable stars to be discovered.
A B star, frequently called a B-type star, is a B-type star with distinctive forbidden neutral or low ionisation emission lines in its spectrum.
The Balmer series or Balmer lines in atomic physics, is the designation of one of a set of six named series describing the spectral line emissions of the hydrogen atom.
Beta Scorpii (β Scorpii, abbreviated Beta Sco, β Sco) is a multiple star system in the southern zodiac constellation of Scorpius.
In astronomy, a blue giant is a hot star with a luminosity class of III (giant) or II (bright giant).
Blue supergiant stars are hot luminous stars, referred to scientifically as OB supergiants.
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.
Cambridge University Press (CUP) is the publishing business of the University of Cambridge.
In astrophysics, chemically peculiar stars (CP stars) are stars with distinctly unusual metal abundances, at least in their surface layers.
The CNO cycle (for carbon–nitrogen–oxygen) is one of the two known sets of fusion reactions by which stars convert hydrogen to helium, the other being the proton–proton chain reaction.
Christmas is an annual festival commemorating the birth of Jesus Christ,Martindale, Cyril Charles.
The Christmas season, also called the festive season, or the holiday season (mainly in the U.S. and Canada; often simply called the holidays),, is an annually recurring period recognized in many Western and Western-influenced countries that is generally considered to run from late November to early January.
Christmas Eve is the evening or entire day before Christmas Day, the festival commemorating the birth of Jesus.
Christmas traditions vary from country to country.
A convection zone, convective zone or convective region of a star is a layer which is unstable to convection.
A corona (Latin, 'crown') is an aura of plasma that surrounds the Sun and other stars.
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.
In physics, electromagnetic radiation (EM radiation or EMR) refers to the waves (or their quanta, photons) of the electromagnetic field, propagating (radiating) through space-time, carrying electromagnetic radiant energy.
Eta Aurigae (η Aurigae, abbreviated Eta Aur, η Aur), also named Haedus, is a star in the northern constellation of Auriga.
Eta Ursae Majoris (η Ursae Majoris, abbreviated Eta UMa, η UMa), also named Alkaid, is a star in the constellation of Ursa Major.
In spectroscopy, a forbidden mechanism (forbidden transition or forbidden line) is a spectral line associated with absorption or emission of light by atomic nuclei, atoms, or molecules which undergo a transition that is not allowed by a particular selection rule but is allowed if the approximation associated with that rule is not made.
Helium (from lit) is a chemical element with symbol He and atomic number 2.
A Herbig Ae/Be star (HAeBe) is a pre-main-sequence star – a young (V. Mannings & A. Sargent (2000) High-resolution studies of gas and dust around young intermediate-mass stars: II. observations of an additional sample of Herbig Ae/Be systems. Astrophysical Journal, vol. 529, p. 391 Hydrogen and calcium emission lines are observed in their spectra. They are 2-8 Solar mass objects, still existing in the star formation (gravitational contraction) stage and approaching the main sequence (i.e. they are not burning hydrogen in their center). In the Hertzsprung–Russell diagram these stars are located to the right of the main sequence. They are named after the American astronomer George Herbig, who first distinguished them from other stars in 1960. The original Herbig criteria were.
HIP 78530 b is an object that is either a planet or a brown dwarf in the orbit of the star HIP 78530.
Hydrogen is a chemical element with symbol H and atomic number 1.
The emission spectrum of atomic hydrogen is divided into a number of spectral series, with wavelengths given by the Rydberg formula.
Ionization or ionisation, is the process by which an atom or a molecule acquires a negative or positive charge by gaining or losing electrons to form ions, often in conjunction with other chemical changes.
Kappa Andromedae b is a substellar object and massive planet or brown dwarf orbiting Kappa Andromedae, a star in the Andromeda constellation, about 170 light years away.
The Kelvin scale is an absolute thermodynamic temperature scale using as its null point absolute zero, the temperature at which all thermal motion ceases in the classical description of thermodynamics.
In astronomy, the main sequence is a continuous and distinctive band of stars that appear on plots of stellar color versus brightness.
New Year is the time or day at which a new calendar year begins and the calendar's year count increments by one.
New Year's Day, also called simply New Year's or New Year, is observed on January 1, the first day of the year on the modern Gregorian calendar as well as the Julian calendar.
In the Gregorian calendar, New Year's Eve (also known as Old Year's Day or Saint Sylvester's Day in many countries), the last day of the year, is on 31 December which is the seventh day of Christmastide.
Omega Fornacis, Latinized from ω Fornacis, is a chemically peculiar class B9.5V (blue main-sequence) star in the constellation Fornax.
There are two stars with the Bayer designation ω Scorpii (omega Scorpii).
In quantum mechanics, perturbation theory is a set of approximation schemes directly related to mathematical perturbation for describing a complicated quantum system in terms of a simpler one.
Princeton University Press is an independent publisher with close connections to Princeton University.
Publications of the Astronomical Society of the Pacific (often abbreviated as PASP in references and literature) is a monthly peer-reviewed scientific journal managed by the Astronomical Society of the Pacific.
Quantum mechanics (QM; also known as quantum physics, quantum theory, the wave mechanical model, or matrix mechanics), including quantum field theory, is a fundamental theory in physics which describes nature at the smallest scales of energy levels of atoms and subatomic particles.
Regulus, also designated Alpha Leonis (α Leonis, abbreviated Alpha Leo, α Leo), is the brightest star in the constellation of Leo and one of the brightest stars in the night sky, lying approximately 79 light years from the Sun.
Rho Aurigae (ρ Aur, ρ Aurigae) is the Bayer designation for a binary star system in the northern constellation of Auriga.
SIMBAD (the Set of Identifications, Measurements, and Bibliography for Astronomical Data) is an astronomical database of objects beyond the Solar System.
The solar mass is a standard unit of mass in astronomy, equal to approximately.
Solar radius is a unit of distance used to express the size of stars in astronomy.
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.
A star is type of astronomical object consisting of a luminous spheroid of plasma held together by its own gravity.
Star counts are bookkeeping surveys of stars and the statistical and geometrical methods used to correct the survey data for bias.
In astronomy, stellar classification is the classification of stars based on their spectral characteristics.
Stellar mass is a phrase that is used by astronomers to describe the mass of a star.
Stellar rotation is the angular motion of a star about its axis.
A stellar wind is a flow of gas ejected from the upper atmosphere of a star.
A B-type subdwarf (sdB) is a kind of subdwarf star with spectral type B. They differ from the typical subdwarf by being much hotter and brighter.
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.
The Sun is the star at the center of the Solar System.
Supergiants are among the most massive and most luminous stars.
The surface gravity, g, of an astronomical or other object is the gravitational acceleration experienced at its surface.
Tau Scorpii (τ Sco, τ Scorpii) is a star in the southern zodiac constellation of Scorpius.
Thermonuclear fusion is a way to achieve nuclear fusion by using extremely high temperatures.
Upsilon Orionis (υ Ori, υ Orionis) is a star in the constellation Orion.
18 Tauri (18 Tau) is a blue main-sequence star in the constellation Taurus.
2018 has been designated as the third International Year of the Reef by the International Coral Reef Initiative.
2019 (MMXIX) will be a common year starting on Tuesday of the Gregorian calendar, the 2019th year of the Common Era (CE) and Anno Domini (AD) designations, the 19th year of the 3rd millennium, the 19th year of the 21st century, and the 10th and last year of the 2010s decade.
22 Scorpii (i Scorpii) is a single star in the southern zodiac constellation of Scorpius.
29 Persei (29 Per) is a class B3V (blue main-sequence) star in the constellation Perseus.
42 Orionis is a class B1V (blue main-sequence) star in the constellation Orion.