J004457+4123 (Sharov 21): not a remarkable nova in M 31 but a background quasar with a spectacular UV flare

H. Meusinger; M. Henze; K. Birkle; W. Pietsch; B. Williams; D. Hatzidimitriou; R. Nesci; H. Mandel; S. Ertel; A. Hinze; T. Berthold

doi:10.1051/0004-6361/200913526

Free Access

Issue		A&A Volume 512, March-April 2010


Article Number		A1
Number of page(s)		14
Section		Extragalactic astronomy
DOI		https://doi.org/10.1051/0004-6361/200913526
Published online		17 March 2010

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