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3C 454.3
3C 454.3 is a blazar (a type of quasar with a jet oriented toward Earth) located away from the galactic plane. It is one of the brightest gamma ray sources in the sky, and is one of the most luminous astronomical object ever observed, with a maximum absolute magnitude of -31.4. It has the brightest blazar gamma ray flare recorded, twice as bright as the Vela Pulsar in the Milky Way galaxy. It also flares at radio and visible wavelengths – in red light, the blazar brightened by more than 2.5 times to magnitude 13.7 – and it is very bright at high radio frequencies. It appears in Pegasus, near Alpha Pegasi (Markab). It has been known to occasionally outburst, brightening to a peak apparent magnitude of 13.4 in June 2014. History In July and August 2007, the gamma-ray blazar 3C 454.3 flared to near-historic levels, only two years after its record-breaking 2005 optical flare. Luckily, Spitzer Space Telescope and Chandra X-ray Observatory were already scheduled for simultan ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Third Cambridge Catalogue Of Radio Sources
The Third Cambridge Catalogue of Radio Sources (3C) is an astronomical catalogue of celestial radio sources detected originally at 159 MHz, and subsequently at 178 MHz. History 3C The catalogue was published in 1959 by members of the Radio Astronomy Group of the University of Cambridge. Entries in the catalogue are identified by the prefix "3C" followed by the entry number, with a space - for example, 3C 273. The catalogue was produced using the Cambridge Interferometer on the west side of Cambridge. The interferometer had previously been used for the Second Cambridge Catalogue of Radio Sources (2C) survey, published in 1955. 3CR The catalogue was subsequently revised by Bennett in 1962 using observations at 178 MHz, and for many years '3CR' was considered as the definitive listing of the brighter radio sources in the Northern Hemisphere. The revision resulted in a number of sources being deleted from the catalogue (as being below the flux limit of 9 Jy or as no ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |