Matches in DBpedia 2016-04 for { <http://dbpedia.org/resource/Cassiopeia_A> ?p ?o }
- Cassiopeia_A abstract "Cassiopeia A (Cas A) is a supernova remnant (SNR) in the constellation Cassiopeia and the brightest extrasolar radio source in the sky at frequencies above 1 GHz. The supernova occurred approximately 11,000 light-years (3.4 kpc) away within the Milky Way. The expanding cloud of material left over from the supernova now appears approximately 10 light-years (3 pc) across from Earth's perspective. In wavelengths of visible light, it has been seen with amateur telescopes down to 234mm (9.25 in) with filters.It is believed that first light from the stellar explosion reached Earth approximately 300 years ago but there are no historical records of any sightings of the supernova that created the remnant, probably due to interstellar dust absorbing optical wavelength radiation before it reached Earth (although it is possible that it was recorded as a sixth magnitude star 3 Cassiopeiae by John Flamsteed on August 16, 1680). Possible explanations lean toward the idea that the source star was unusually massive and had previously ejected much of its outer layers. These outer layers would have cloaked the star and re-absorbed much of the light released as the inner star collapsed.Cas A was among the first discrete astronomical radio sources found. Its discovery was reported in 1948 by Martin Ryle and Francis Graham-Smith, astronomers at Cambridge, based on observations with the Long Michelson Interferometer. The optical component was first identified in 1950.In 2013, it was reported that phosphorus had been detected in Cassiopeia A, which confirmed that this element is produced in supernovae, with the Phosphorus-Iron ratio up to 100 times higher in material from the supernova remnant than in the Milky Way in general.Cas A is 3C461 in the Third Cambridge Catalogue of Radio Sources and G111.7-2.1 in the Green Catalog of Supernova Remnants.".
- Cassiopeia_A thumbnail Cassiopeia_A_Spitzer_Crop.jpg?width=300.
- Cassiopeia_A wikiPageExternalLink 7814351.stm.
- Cassiopeia_A wikiPageID "1996903".
- Cassiopeia_A wikiPageLength "13425".
- Cassiopeia_A wikiPageOutDegree "63".
- Cassiopeia_A wikiPageRevisionID "699202715".
- Cassiopeia_A wikiPageWikiLink 3_Cassiopeiae.
- Cassiopeia_A wikiPageWikiLink Aerobee.
- Cassiopeia_A wikiPageWikiLink Astronomer_Royal.
- Cassiopeia_A wikiPageWikiLink Astronomical_radio_source.
- Cassiopeia_A wikiPageWikiLink BBC_News.
- Cassiopeia_A wikiPageWikiLink Black_hole.
- Cassiopeia_A wikiPageWikiLink Cassiopeia_(constellation).
- Cassiopeia_A wikiPageWikiLink Category:1947_in_science.
- Cassiopeia_A wikiPageWikiLink Category:3C_objects.
- Cassiopeia_A wikiPageWikiLink Category:Astronomical_objects_discovered_in_1680.
- Cassiopeia_A wikiPageWikiLink Category:Astronomical_objects_discovered_in_1947.
- Cassiopeia_A wikiPageWikiLink Category:Cassiopeia_(constellation).
- Cassiopeia_A wikiPageWikiLink Category:Milky_Way.
- Cassiopeia_A wikiPageWikiLink Category:Supernova_remnants.
- Cassiopeia_A wikiPageWikiLink Chandra_X-ray_Observatory.
- Cassiopeia_A wikiPageWikiLink Charles_II_of_England.
- Cassiopeia_A wikiPageWikiLink Constellation.
- Cassiopeia_A wikiPageWikiLink Cosmic_dust.
- Cassiopeia_A wikiPageWikiLink Cygnus_A.
- Cassiopeia_A wikiPageWikiLink Declination.
- Cassiopeia_A wikiPageWikiLink Fahrenheit.
- Cassiopeia_A wikiPageWikiLink Francis_Graham-Smith.
- Cassiopeia_A wikiPageWikiLink Green_Catalogue_of_Supernova_Remnants.
- Cassiopeia_A wikiPageWikiLink Hertz.
- Cassiopeia_A wikiPageWikiLink Hubble_Space_Telescope.
- Cassiopeia_A wikiPageWikiLink Iosif_Shklovsky.
- Cassiopeia_A wikiPageWikiLink Jansky.
- Cassiopeia_A wikiPageWikiLink John_Flamsteed.
- Cassiopeia_A wikiPageWikiLink Kelvin.
- Cassiopeia_A wikiPageWikiLink Light_echo.
- Cassiopeia_A wikiPageWikiLink List_of_supernova_remnants.
- Cassiopeia_A wikiPageWikiLink Long_Michelson_Interferometer.
- Cassiopeia_A wikiPageWikiLink Martin_Ryle.
- Cassiopeia_A wikiPageWikiLink Milky_Way.
- Cassiopeia_A wikiPageWikiLink Minute_and_second_of_arc.
- Cassiopeia_A wikiPageWikiLink Neutron_star.
- Cassiopeia_A wikiPageWikiLink Phosphorus.
- Cassiopeia_A wikiPageWikiLink Red_supergiant.
- Cassiopeia_A wikiPageWikiLink Right_ascension.
- Cassiopeia_A wikiPageWikiLink Sounding_rocket.
- Cassiopeia_A wikiPageWikiLink Spitzer_Space_Telescope.
- Cassiopeia_A wikiPageWikiLink Star.
- Cassiopeia_A wikiPageWikiLink Supernova.
- Cassiopeia_A wikiPageWikiLink Supernova_remnant.
- Cassiopeia_A wikiPageWikiLink Third_Cambridge_Catalogue_of_Radio_Sources.
- Cassiopeia_A wikiPageWikiLink University_of_Cambridge.
- Cassiopeia_A wikiPageWikiLink William_Ashworth_(historian).
- Cassiopeia_A wikiPageWikiLink File:Cassiopeia_A_Spitzer_Crop.jpg.
- Cassiopeia_A wikiPageWikiLink File:Heic0609.jpg.
- Cassiopeia_A wikiPageWikiLinkText "Cas A".
- Cassiopeia_A wikiPageWikiLinkText "Cassieopeia A supernova remnant".
- Cassiopeia_A wikiPageWikiLinkText "Cassiopeia A".
- Cassiopeia_A bV "Unknown".
- Cassiopeia_A caption "A false color image composited of data from three sources. Red is infrared data from the Spitzer Space Telescope, orange is visible data from the Hubble Space Telescope, and blue and green are data from the Chandra X-ray Observatory. The cyan dot just off-center is the remnant of the star's core.".
- Cassiopeia_A constellation Cassiopeia_(constellation).
- Cassiopeia_A dec "+58° 48′".
- Cassiopeia_A discovery "1947".
- Cassiopeia_A epoch "J2000".
- Cassiopeia_A gal "G111.7-2.1".
- Cassiopeia_A host Milky_Way.
- Cassiopeia_A magV "6".
- Cassiopeia_A name "Cassiopeia A".
- Cassiopeia_A notes "Strongest radio source beyond our solar system".
- Cassiopeia_A progenitor "Unknown".
- Cassiopeia_A progenitorType "Unknown".
- Cassiopeia_A ra "84206.0".
- Cassiopeia_A sizeV "5".
- Cassiopeia_A snrtype "Shell".
- Cassiopeia_A type Supernova.
- Cassiopeia_A wikiPageUsesTemplate Template:Commons_category.
- Cassiopeia_A wikiPageUsesTemplate Template:Convert.
- Cassiopeia_A wikiPageUsesTemplate Template:DEC.
- Cassiopeia_A wikiPageUsesTemplate Template:Dec.
- Cassiopeia_A wikiPageUsesTemplate Template:RA.
- Cassiopeia_A wikiPageUsesTemplate Template:Reflist.
- Cassiopeia_A wikiPageUsesTemplate Template:Supernova.
- Cassiopeia_A subject Category:1947_in_science.
- Cassiopeia_A subject Category:3C_objects.
- Cassiopeia_A subject Category:Astronomical_objects_discovered_in_1680.
- Cassiopeia_A subject Category:Astronomical_objects_discovered_in_1947.
- Cassiopeia_A subject Category:Cassiopeia_(constellation).
- Cassiopeia_A subject Category:Milky_Way.
- Cassiopeia_A subject Category:Supernova_remnants.
- Cassiopeia_A hypernym Remnant.
- Cassiopeia_A type Event.
- Cassiopeia_A type Place.
- Cassiopeia_A type Event.
- Cassiopeia_A type Object.
- Cassiopeia_A type Remnant.
- Cassiopeia_A type Survey.
- Cassiopeia_A comment "Cassiopeia A (Cas A) is a supernova remnant (SNR) in the constellation Cassiopeia and the brightest extrasolar radio source in the sky at frequencies above 1 GHz. The supernova occurred approximately 11,000 light-years (3.4 kpc) away within the Milky Way. The expanding cloud of material left over from the supernova now appears approximately 10 light-years (3 pc) across from Earth's perspective.".
- Cassiopeia_A label "Cassiopeia A".
- Cassiopeia_A sameAs Q618273.