31 relations: Apparent magnitude, Aquila (constellation), Astronomical unit, Bayer designation, Bright Star Catalogue, Catalogues of Fundamental Stars, Celestial equator, Constellation, CSIRO, Double star, Durchmusterung, Effective temperature, Flamsteed designation, Gliese Catalogue of Nearby Stars, Henry Draper Catalogue, Hipparcos, Jupiter mass, Light-year, McDonald Observatory, Metallicity, Minute and second of arc, New Catalogue of Suspected Variable Stars, NGC 188, Parallax, Smithsonian Astrophysical Observatory Star Catalog, Star, Star catalogue, Stellar atmosphere, Stellar classification, Subgiant, Variable star.
The apparent magnitude of a celestial object is a number that is a measure of its brightness as seen by an observer on Earth.
Aquila is a constellation on the celestial equator.
The astronomical unit (symbol: au, ua, or AU) is a unit of length, roughly the distance from Earth to the Sun.
A Bayer designation is a stellar designation in which a specific star is identified by a Greek letter, followed by the genitive form of its parent constellation's Latin name.
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.
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.
The celestial equator is the great circle of the imaginary celestial sphere on the same plane as the equator of Earth.
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 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.
The Commonwealth Scientific and Industrial Research Organisation (CSIRO) is an independent Australian federal government agency responsible for scientific research.
In observational astronomy, a double star or visual double is a pair of stars that appear close to each other in the sky as seen from Earth when viewed through an optical telescope.
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.
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.
A Flamsteed designation is a combination of a number and constellation name that uniquely identifies most naked eye stars in the modern constellations visible from southern England.
The Gliese Catalogue of Nearby Stars is a modern star catalogue of stars located within 25 parsecs (81.54 ly) of the Earth.
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.
Hipparcos was a scientific satellite of the European Space Agency (ESA), launched in 1989 and operated until 1993.
Jupiter mass, also called Jovian mass is the unit of mass equal to the total mass of the planet Jupiter.
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 McDonald Observatory is an astronomical observatory located near the unincorporated community of Fort Davis in Jeff Davis County, Texas, United States.
In astronomy, metallicity is used to describe the abundance of elements present in an object that are heavier than hydrogen or helium.
A minute of arc, arcminute (arcmin), arc minute, or minute arc is a unit of angular measurement equal to of one degree.
The New Catalogue of Suspected Variable Stars (NSV) is a star catalogue containing 14,811 stars which, although suspected to be variable, were not given variable star designations prior to 1980.
NGC 188 is an open cluster in the constellation Cepheus.
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.
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.
The Smithsonian Astrophysical Observatory Star Catalog is an astrometric star catalogue.
A star is type of astronomical object consisting of a luminous spheroid of plasma held together by its own gravity.
A star catalogue (Commonwealth English) or star catalog (American English), is an astronomical catalogue that lists stars.
The stellar atmosphere is the outer region of the volume of a star, lying above the stellar core, radiation zone and convection zone.
In astronomy, stellar classification is the classification of stars based on their spectral characteristics.
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.
A variable star is a star whose brightness as seen from Earth (its apparent magnitude) fluctuates.
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.