33 relations: Absolute magnitude, Andromeda Galaxy, Binary star, BL Herculis variable, Blazhko effect, Canada–France–Hawaii Telescope, Cepheid variable, Classical Cepheid variable, Cosmic distance ladder, Edward Charles Pickering, Gaia (spacecraft), Galaxy, Globular cluster, Horizontal branch, Hubble Space Telescope, Hubble's law, Instability strip, Jacobus Kapteyn, K band (infrared), Kappa mechanism, Kepler (spacecraft), Local Group, Red-giant branch, RR Lyrae, Solon Irving Bailey, Stellar classification, Stellar population, Sun, Type II Cepheid, Variable star, W Virginis variable, Walter Baade, Williamina Fleming.
Absolute magnitude is a measure of the luminosity of a celestial object, on a logarithmic astronomical magnitude scale.
The Andromeda Galaxy, also known as Messier 31, M31, or NGC 224, is a spiral galaxy approximately 780 kiloparsecs (2.5 million light-years) from Earth, and the nearest major galaxy to the Milky Way.
A binary star is a star system consisting of two stars orbiting around their common barycenter.
BL Herculis variables are a type of variable star with low luminosity and mass that have a period of less than eight days.
The Blazhko effect, which is sometimes called long-period modulation, is a variation in period and amplitude in RR Lyrae type variable stars.
The Canada–France–Hawaii Telescope (CFHT) is located near the summit of Mauna Kea mountain on Hawaii's Big Island at an altitude of 4,204 meters (13,793 feet), and is one of the observatories that comprise the Mauna Kea Observatories.
A Cepheid variable is a type of star that pulsates radially, varying in both diameter and temperature and producing changes in brightness with a well-defined stable period and amplitude.
Classical Cepheids (also known as Population I Cepheids, Type I Cepheids, or Delta Cephei variables) are a type of Cepheid variable star.
The cosmic distance ladder (also known as the extragalactic distance scale) is the succession of methods by which astronomers determine the distances to celestial objects.
Prof Edward Charles Pickering FRS(For) HFRSE (July 19, 1846 – February 3, 1919) was an American astronomer and physicist and the older brother to William Henry Pickering.
Gaia is a space observatory of the European Space Agency (ESA) designed for astrometry: measuring the positions and distances of stars with unprecedented precision.
A galaxy is a gravitationally bound system of stars, stellar remnants, interstellar gas, dust, and dark matter.
A globular cluster is a spherical collection of stars that orbits a galactic core as a satellite.
The horizontal branch (HB) is a stage of stellar evolution that immediately follows the red giant branch in stars whose masses are similar to the Sun's.
The Hubble Space Telescope (HST) is a space telescope that was launched into low Earth orbit in 1990 and remains in operation.
Hubble's law is the name for the observation in physical cosmology that.
The unqualified term instability strip usually refers to a region of the Hertzsprung–Russell diagram largely occupied by several related classes of pulsating variable stars: Delta Scuti variables, SX Phoenicis variables, and rapidly oscillating Ap stars (roAps) near the main sequence; RR Lyrae variables where it intersects the horizontal branch; and the Cepheid variables where it crosses the supergiants.
Prof Jacobus Cornelius Kapteyn FRS FRSE LLD (19 January 1851 – 18 June 1922) was a Dutch astronomer.
In infrared astronomy, the K band is an atmospheric transmission window centered on 2.2 μm (in the near-infrared 136 THz range).
The κ–mechanism is the driving mechanism behind the changes in luminosity of many types of pulsating variable stars.
Kepler is a space observatory launched by NASA to discover Earth-size planets orbiting other stars.
The Local Group is the galaxy group that includes the Milky Way.
The red-giant branch (RGB), sometimes called the first giant branch, is the portion of the giant branch before helium ignition occurs in the course of stellar evolution.
RR Lyrae is a variable star in the Lyra constellation, located near the border with the neighboring constellation of Cygnus.
Solon Irving Bailey (December 29, 1854 in Lisbon, New Hampshire – June 5, 1931 in Norwell, Massachusetts) was an American astronomer and discoverer of the main-belt asteroid 504 Cora, on June 30, 1902.
In astronomy, stellar classification is the classification of stars based on their spectral characteristics.
During 1944, Walter Baade categorized groups of stars within the Milky Way into bluer stars associated with the spiral arms and the general position of yellow stars near the central galactic bulge or within globular star clusters.
The Sun is the star at the center of the Solar System.
Type II Cepheids are variable stars which pulsate with periods typically between 1 and 50 days.
A variable star is a star whose brightness as seen from Earth (its apparent magnitude) fluctuates.
W Virginis variables are a subclass of Type II Cepheids which exhibit pulsation periods between 10–20 days,Wallerstein, G.,, Publications of the Astronomical Society of the Pacific, 114 p.689–699 (2002) and are of spectral class F6 – K2.
Wilhelm Heinrich Walter Baade (March 24, 1893 – June 25, 1960) was a German astronomer who worked in the United States from 1931 to 1959.
Williamina Paton Stevens Fleming (May 15, 1857 – May 21, 1911) was a Scottish-American astronomer.