Matches in DBpedia 2015-10 for { <http://dbpedia.org/resource/BY_Draconis> ?p ?o }
- BY_Draconis abstract "BY Draconis is a multi-star system in the constellation Draco. It consists of at least three components. Components A and B form a close binary star system with a short orbital period of only 5.98 days. These may be pre-main sequence objects that are still in the process of collapsing. Their individual spectroscopic classifications are dK5e and dK7e. They form the prototype of a class of variable stars known as BY Draconis variables.The third component (C) is, by comparison, widely separated from the A-B pair by an angular distance of 17 arcseconds, which corresponds to 260 AU at the estimated distance of this star system—where an AU is the average distance from the Earth to the Sun. Component C is an M5 class red dwarf star. There may be a fourth component to the system, orbiting with a 114 day period, but this has not been visually confirmed.The variability of BY Draconis is caused by activity in the stellar photosphere called starspots, which are comparable to sunspots on the Sun, in combination with rapid rotation that changes the viewing angle of the activity relative to the observer. This variation has an average periodicity of 3.8285 days, but the brightness also changes over the course of several years—depending on the level of surface activity. Most observers believe that the primary star (A) is responsible for the variability as the secondary produces only a third of the total luminosity from the system. However, the spots may occur on both stars. Unlike the Sun, these spots may occur in the polar regions of the stars.".
- BY_Draconis wikiPageExternalLink BY_Draconis_star.html.
- BY_Draconis wikiPageID "16996815".
- BY_Draconis wikiPageLength "4830".
- BY_Draconis wikiPageOutDegree "32".
- BY_Draconis wikiPageRevisionID "635305727".
- BY_Draconis wikiPageWikiLink Angular_distance.
- BY_Draconis wikiPageWikiLink Arcsecond.
- BY_Draconis wikiPageWikiLink Astronomical_Unit.
- BY_Draconis wikiPageWikiLink Astronomical_unit.
- BY_Draconis wikiPageWikiLink BY_Draconis_variable.
- BY_Draconis wikiPageWikiLink Binary_star.
- BY_Draconis wikiPageWikiLink Bonner_Durchmusterung.
- BY_Draconis wikiPageWikiLink Category:BY_Draconis_variables.
- BY_Draconis wikiPageWikiLink Category:Draco_(constellation).
- BY_Draconis wikiPageWikiLink Category:Henry_Draper_Catalogue_objects.
- BY_Draconis wikiPageWikiLink Category:K-type_main-sequence_stars.
- BY_Draconis wikiPageWikiLink Category:Objects_named_with_variable_star_designations.
- BY_Draconis wikiPageWikiLink Constellation.
- BY_Draconis wikiPageWikiLink Draco_(constellation).
- BY_Draconis wikiPageWikiLink Durchmusterung.
- BY_Draconis wikiPageWikiLink Earth.
- BY_Draconis wikiPageWikiLink Gliese-Jahreiss_catalogue.
- BY_Draconis wikiPageWikiLink Gliese_Catalogue_of_Nearby_Stars.
- BY_Draconis wikiPageWikiLink Henry_Draper_Catalogue.
- BY_Draconis wikiPageWikiLink Henry_Draper_catalogue.
- BY_Draconis wikiPageWikiLink Hipparcos.
- BY_Draconis wikiPageWikiLink Hipparcos_catalogue.
- BY_Draconis wikiPageWikiLink Luyten_Two-Tenths_catalogue.
- BY_Draconis wikiPageWikiLink Main_sequence.
- BY_Draconis wikiPageWikiLink Minute_and_second_of_arc.
- BY_Draconis wikiPageWikiLink Orbital_period.
- BY_Draconis wikiPageWikiLink Photosphere.
- BY_Draconis wikiPageWikiLink Red_dwarf.
- BY_Draconis wikiPageWikiLink Smithsonian_Astrophysical_Observatory.
- BY_Draconis wikiPageWikiLink Spectral_classification.
- BY_Draconis wikiPageWikiLink Spectroscopy.
- BY_Draconis wikiPageWikiLink Star_catalogue.
- BY_Draconis wikiPageWikiLink Starspot.
- BY_Draconis wikiPageWikiLink Stellar_classification.
- BY_Draconis wikiPageWikiLink Stellar_rotation.
- BY_Draconis wikiPageWikiLink Sun.
- BY_Draconis wikiPageWikiLink Sunspot.
- BY_Draconis wikiPageWikiLink Variable_star.
- BY_Draconis wikiPageWikiLinkText "BY Dra".
- BY_Draconis wikiPageWikiLinkText "BY Draconis Type".
- BY_Draconis wikiPageWikiLinkText "BY Draconis".
- BY_Draconis appmagV "8.07".
- BY_Draconis axis "4.4".
- BY_Draconis bV "+1.19".
- BY_Draconis class "K6Ve".
- BY_Draconis constell Draco_(constellation).
- BY_Draconis eccentricity "0.298".
- BY_Draconis epoch "J2000".
- BY_Draconis hasPhotoCollection BY_Draconis.
- BY_Draconis inclination "151.8".
- BY_Draconis name "BY Dra B".
- BY_Draconis pError "0.73".
- BY_Draconis parallax "60.9".
- BY_Draconis period "0.01637".
- BY_Draconis propMoDec "−324.90".
- BY_Draconis propMoRa "186.62".
- BY_Draconis radialV "−27±5".
- BY_Draconis uB "+0.99".
- BY_Draconis variable BY_Draconis_variable.
- BY_Draconis wikiPageUsesTemplate Template:Cite_web.
- BY_Draconis wikiPageUsesTemplate Template:Reflist.
- BY_Draconis wikiPageUsesTemplate Template:Starbox_astrometry.
- BY_Draconis wikiPageUsesTemplate Template:Starbox_begin.
- BY_Draconis wikiPageUsesTemplate Template:Starbox_catalog.
- BY_Draconis wikiPageUsesTemplate Template:Starbox_character.
- BY_Draconis wikiPageUsesTemplate Template:Starbox_end.
- BY_Draconis wikiPageUsesTemplate Template:Starbox_observe.
- BY_Draconis wikiPageUsesTemplate Template:Starbox_visbin.
- BY_Draconis wikiPageUsesTemplate Template:Stars_of_Draco.
- BY_Draconis subject Category:BY_Draconis_variables.
- BY_Draconis subject Category:Draco_(constellation).
- BY_Draconis subject Category:Henry_Draper_Catalogue_objects.
- BY_Draconis subject Category:K-type_main-sequence_stars.
- BY_Draconis subject Category:Objects_named_with_variable_star_designations.
- BY_Draconis hypernym System.
- BY_Draconis type CelestialBody.
- BY_Draconis type Place.
- BY_Draconis type Star.
- BY_Draconis type Variable.
- BY_Draconis type Location.
- BY_Draconis type Place.
- BY_Draconis type Thing.
- BY_Draconis comment "BY Draconis is a multi-star system in the constellation Draco. It consists of at least three components. Components A and B form a close binary star system with a short orbital period of only 5.98 days. These may be pre-main sequence objects that are still in the process of collapsing. Their individual spectroscopic classifications are dK5e and dK7e.".
- BY_Draconis label "BY Draconis".
- BY_Draconis sameAs BY_Draconis.
- BY_Draconis sameAs BY_Draconis.
- BY_Draconis sameAs بیوای_اژدها.
- BY_Draconis sameAs りゅう座BY星.
- BY_Draconis sameAs m.0414zwc.
- BY_Draconis sameAs BY_Дракона.
- BY_Draconis sameAs Q2660608.
- BY_Draconis sameAs Q2660608.
- BY_Draconis sameAs 天龍座BY.
- BY_Draconis wasDerivedFrom BY_Draconis?oldid=635305727.