25 relations: American Association of Variable Star Observers, Be star, Binary star, Boss General Catalogue, British Astronomical Association, Cepheus (constellation), Cepheus OB1, Constellation, Durchmusterung, General Catalogue of Variable Stars, Guide Star Catalog, Henry Draper Catalogue, Hipparcos, IRAS, PPM Star Catalogue, Semiregular variable star, Smithsonian Astrophysical Observatory Star Catalog, Speckle imaging, Spectral line, Stellar association, Supergiant star, USNO CCD Astrograph Catalog, Variable star, Variable star designation, 2MASS.
Since its founding in 1911, the American Association of Variable Star Observers (AAVSO) has coordinated, collected, evaluated, analyzed, published, and archived variable star observations made largely by amateur astronomers and makes the records available to professional astronomers, researchers, and educators.
Be Stars are a heterogeneous set of stars with B spectral types and emission lines.
A binary star is a star system consisting of two stars orbiting around their common barycenter.
Boss General Catalogue (GC, sometimes General Catalogue) is an astronomical catalogue containing 33,342 stars.
The British Astronomical Association (BAA) was formed in 1890 as a national body to support the UK's amateur astronomers.
Cepheus is a constellation in the northern sky, which is named after Cepheus (a King in the Greek mythology).
Cepheus OB1 is an OB association around the cluster NGC 7380.
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.
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 General Catalogue of Variable Stars (GCVS) is a list of variable stars.
The Guide Star Catalog (GSC), also known as the Hubble Space Telescope, Guide Catalog (HSTGC), is a star catalog compiled to support the Hubble Space Telescope with targeting off-axis stars.
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.
The Infrared Astronomical Satellite (IRAS) was the first-ever space telescope to perform a survey of the entire night sky at infrared wavelengths.
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.
The PPM Star Catalogue (Positions and Proper Motions Star Catalogue) is the successor of the SAO Catalogue.
Semiregular variable stars are giants or supergiants of intermediate and late spectral type showing considerable periodicity in their light changes, accompanied or sometimes interrupted by various irregularities.
The Smithsonian Astrophysical Observatory Star Catalog is an astrometric star catalogue.
Image:Zeta_bootis_short_exposure.png|Typical short-exposure image of a binary star (Zeta Bootis in this case) as seen through atmospheric seeing.
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 stellar association is a very loose star cluster, looser than both open clusters and globular clusters.
Supergiants are among the most massive and most luminous stars.
The USNO CCD Astrograph Catalog (UCAC) is an astrometric star catalog of the United States Naval Observatory.
A variable star is a star whose brightness as seen from Earth (its apparent magnitude) fluctuates.
Variable stars are designated using a variation on the Bayer designation format of an identifying label (as described below) combined with the Latin genitive of the name of the constellation in which the star lies.
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.
The Two Micron All-Sky Survey, or 2MASS, was an astronomical survey of the whole sky in the infrared spectrum and one of the most ambitious such projects.