Antoranz Canales, PedroBarrio Uña, Juan AbelContreras González, José LuisFonseca González, María VictoriaMiranda Pantoja, José MiguelNieto Castaño, Daniel2023-06-202023-06-202008-06-270036-807510.1126/science.1157087https://hdl.handle.net/20.500.14352/50832© American Association for the Advancement of Science. We thank the Instituto de Astrofisica de Canarias for the excellent working conditions at the Observatorio del Roque de los Muchachos in La Palma, Canary Islands. The support of the German Bundesministerium für Bildung und Forschung and Max-Planck Gesellschaft, the Italian Istituto Nazionale di Fisica Nucleare (INFN) and Spanish Centro de nvestigación Científica y Technologia is gratefully acknowledged. This work was also supported by ETH (research grant TH 34/043) and the Polish MNil (grant 1P03D01028).The atmospheric Cherenkov gamma- ray telescope MAGIC, designed for a low- energy threshold, has detected very- high- energy gamma rays from a giant flare of the distant Quasi- Stellar Radio Source ( in short: radio quasar) 3C 279, at a distance of more than 5 billion light- years ( a redshift of 0.536). No quasar has been observed previously in very- high- energy gamma radiation, and this is also the most distant object detected emitting gamma rays above 50 gigaelectron volts. Because high- energy gamma rays may be stopped by interacting with the diffuse background light in the universe, the observations by MAGIC imply a low amount for such light, consistent with that known from galaxy counts.engjournal articlehttp://dx.doi.org/10.1126/science.1157087http://www.sciencemag.orghttp://arxiv.org/abs/0807.2822open access537539.1Extragalactic Background LightTelescopeRadiation3C-279Counts.Electrónica (Física)ElectricidadFísica nuclear2202.03 Electricidad2207 Física Atómica y Nuclear