14 relations: A-type main-sequence star, Apparent magnitude, Bright Star Catalogue, Constellation, Double star, Equuleus, Hipparcos, Kilometre, Light-year, List of stars in Equuleus, Orbit, Second, Sun, Year.
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.
The apparent magnitude (m) of a celestial object is a measure of its brightness as seen by an observer on Earth, adjusted to the value it would have in the absence of the atmosphere.
New!!: HD 199942 and Apparent magnitude ·
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.
New!!: HD 199942 and Bright Star Catalogue ·
In modern astronomy, a constellation is a specific area of the celestial sphere as defined by the International Astronomical Union (IAU).
New!!: HD 199942 and Constellation ·
In observational astronomy, a double star is a pair of stars that appear close to each other in the sky as seen from Earth when viewed through an optical telescope.
New!!: HD 199942 and Double star ·
Equuleus is a constellation.
New!!: HD 199942 and Equuleus ·
Hipparcos was a scientific satellite of the European Space Agency (ESA), launched in 1989 and operated until 1993.
New!!: HD 199942 and Hipparcos ·
The kilometre (International spelling as used by the International Bureau of Weights and Measures; SI symbol: km; or) or kilometer (American spelling) is a unit of length in the metric system, equal to one thousand metres (kilo- being the SI prefix for). It is now the measurement unit used officially for expressing distances between geographical places on land in most of the world; notable exceptions are the United States and the United Kingdom where the statute mile is the official unit used.
New!!: HD 199942 and Kilometre ·
A light-year (abbreviation: ly), sometimes written light year, is a unit of length used informally to express astronomical distances.
New!!: HD 199942 and Light-year ·
This is the list of notable stars in the constellation Equuleus, sorted by decreasing brightness.
In physics, an orbit is the gravitationally curved path of an object around a point in space, for example the orbit of a planet around the center of a star system, such as the Solar System.
New!!: HD 199942 and Orbit ·
The second (symbol: s) (abbreviated s or sec) is the base unit of time in the International System of Units (SI).
New!!: HD 199942 and Second ·
The Sun (in Greek: Helios, in Latin: Sol) is the star at the center of the Solar System and is by far the most important source of energy for life on Earth.
New!!: HD 199942 and Sun ·
A year is the orbital period of the Earth moving in its orbit around the Sun.
New!!: HD 199942 and Year ·