28 relations: Andromeda Galaxy, Asymptotic giant branch, Caldwell catalogue, Cassiopeia (constellation), Constellation, David Dunlap Observatory Catalogue, Dwarf spheroidal galaxy, Epoch (astronomy), H I region, Interstellar medium, John Herschel, Light-year, List of Andromeda's satellite galaxies, Local Group, Los Angeles, Metallicity, Monthly Notices of the Royal Astronomical Society, Mount Wilson (California), New General Catalogue, NGC 185, Parsec, Principal Galaxies Catalogue, Satellite galaxy, Second, Telescope, Tip of the red-giant branch, Uppsala General Catalogue, Walter Baade.
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.
The asymptotic giant branch (AGB) is a region of the Hertzsprung–Russell diagram populated by evolved cool luminous stars.
The Caldwell Catalogue is an astronomical catalogue of 109 star clusters, nebulae, and galaxies for observation by amateur astronomers.
Cassiopeia is a constellation in the northern sky, named after the vain queen Cassiopeia in Greek mythology, who boasted about her unrivalled beauty.
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.
David Dunlap Observatory Catalogue, known as the DDO or A Catalogue of Dwarf Galaxies, is a catalogue of dwarf galaxies that was published in 1959 (and later expanded in 1966) by Sidney van den Bergh.
A dwarf spheroidal galaxy (dSph) is a term in astronomy applied to small, low-luminosity galaxies with very little dust and an older stellar population.
In astronomy, an epoch is a moment in time used as a reference point for some time-varying astronomical quantity, such as the celestial coordinates or elliptical orbital elements of a celestial body, because these are subject to perturbations and vary with time.
An HI region or H I region (read H one) is a cloud in the interstellar medium composed of neutral atomic hydrogen (HI), in addition to the local abundance of helium and other elements.
In astronomy, the interstellar medium (ISM) is the matter and radiation that exists in the space between the star systems in a galaxy.
Sir John Frederick William Herschel, 1st Baronet (7 March 1792 – 11 May 1871) was an English polymath, mathematician, astronomer, chemist, inventor, experimental photographer who invented the blueprint, and did botanical work.
The light-year is a unit of length used to express astronomical distances and measures about 9.5 trillion kilometres or 5.9 trillion miles.
The Andromeda Galaxy (M31) has satellite galaxies just like the Milky Way.
The Local Group is the galaxy group that includes the Milky Way.
Los Angeles (Spanish for "The Angels";; officially: the City of Los Angeles; colloquially: by its initials L.A.) is the second-most populous city in the United States, after New York City.
In astronomy, metallicity is used to describe the abundance of elements present in an object that are heavier than hydrogen or helium.
Monthly Notices of the Royal Astronomical Society (MNRAS) is a peer-reviewed scientific journal covering research in astronomy and astrophysics.
Mount Wilson is a peak in the San Gabriel Mountains, located within the San Gabriel Mountains National Monument and Angeles National Forest in Los Angeles County, California.
The New General Catalogue of Nebulae and Clusters of Stars (abbreviated as NGC) is a catalogue of deep-sky objects compiled by John Louis Emil Dreyer in 1888.
NGC 185 (also known as Caldwell 18) is a dwarf spheroidal galaxy located 2.08 million light-years from Earth, appearing in the constellation Cassiopeia.
The parsec (symbol: pc) is a unit of length used to measure large distances to astronomical objects outside the Solar System.
The Catalogue of Principal Galaxies (PGC) is an astronomical catalog published in 1989 that lists B1950 and J2000 equatorial coordinates and cross-identifications for 73,197 galaxies.
A satellite galaxy is a smaller companion galaxy that travels on bound orbits within the gravitational potential of a more massive and luminous host galaxy (also known as the primary galaxy).
The second is the SI base unit of time, commonly understood and historically defined as 1/86,400 of a day – this factor derived from the division of the day first into 24 hours, then to 60 minutes and finally to 60 seconds each.
A telescope is an optical instrument that aids in the observation of remote objects by collecting electromagnetic radiation (such as visible light).
Tip of the red-giant branch (TRGB) is a primary distance indicator used in astronomy.
The Uppsala General Catalogue of Galaxies (UGC) is a catalogue of 12,921 galaxies visible from the northern hemisphere.
Wilhelm Heinrich Walter Baade (March 24, 1893 – June 25, 1960) was a German astronomer who worked in the United States from 1931 to 1959.