Editor's Summary
28 April 2005
Flares back in fashion
On 27 December last year, SGR1806−20, a soft 
-ray repeater in Sagittarius, released a giant flare that has been called the brightest explosion ever recorded. SGRs are X-ray stars that sporadically emit low-energy -ray bursts. They are thought to be magnetars: neutron stars with observable emissions powered by magnetic dissipation. Five papers in this issue report initial and follow-up observations of this event. The data are remarkable: for instance in a fifth of a second, the flare released as much energy as the Sun radiates in a quarter of a million years. Such power can be explained by catastrophic global crust failure and magnetic reconnection on a magnetar. Releasing a hundred times the energy of the only two previous SGR giant flares, this may have been a once-in-a-lifetime event for astronomers, and for the star itself.
News and Views: Astrophysics: A certain flare
Giant flashes from soft -ray repeaters are spectacular but rare events — only three have ever been observed in our Galaxy. The suspicion is that we have been missing some from farther afield.
Davide Lazzati
doi: 10.1038/4341075a
Article: An exceptionally bright flare from SGR 1806−20 and the origins of short-duration 
-ray bursts
K. Hurley, S. E. Boggs, D. M. Smith, R. C. Duncan, R. Lin, A. Zoglauer, S. Krucker, G. Hurford, H. Hudson, C. Wigger, W. Hajdas, C. Thompson, I. Mitrofanov, A. Sanin, W. Boynton, C. Fellows, A. von Kienlin, G. Lichti, A. Rau and T. Cline
doi: 10.1038/nature03519
Abstract | Full Text | PDF (274K) | Supplementary information
Letter: An expanding radio nebula produced by a giant flare from the magnetar SGR 1806−20
B. M. Gaensler, C. Kouveliotou, J. D. Gelfand, G. B. Taylor, D. Eichler, R. A. M. J. Wijers, J. Granot, E. Ramirez-Ruiz, Y. E. Lyubarsky, R. W. Hunstead, D. Campbell-Wilson, A. J. van der Horst, M. A. McLaughlin, R. P. Fender, M. A. Garrett, K. J. Newton-McGee, D. M. Palmer, N. Gehrels and P. M. Woods
doi: 10.1038/nature03498
First paragraph | Full Text | PDF (255K) | Supplementary information
Letter: A giant -ray flare from the magnetar SGR 1806−20
D. M. Palmer, S. Barthelmy, N. Gehrels, R. M. Kippen, T. Cayton, C. Kouveliotou, D. Eichler, R. A. M. J. Wijers, P. M. Woods, J. Granot, Y. E. Lyubarsky, E. Ramirez-Ruiz, L. Barbier, M. Chester, J. Cummings, E. E. Fenimore, M. H. Finger, B. M. Gaensler, D. Hullinger, H. Krimm, C. B. Markwardt, J. A. Nousek, A. Parsons, S. Patel, T. Sakamoto, G. Sato, M. Suzuki and J. Tueller
doi: 10.1038/nature03525
First paragraph | Full Text | PDF (214K) | Supplementary information
Letter: Repeated injections of energy in the first 600 ms of the giant flare of SGR 1806−20
Toshio Terasawa, Yasuyuki T. Tanaka, Yasuhiro Takei, Nobuyuki Kawai, Atsumasa Yoshida, Ken'ichi Nomoto, Ichiro Yoshikawa, Yoshifumi Saito, Yasumasa Kasaba, Takeshi Takashima, Toshifumi Mukai, Hirotomo Noda, Toshio Murakami, Kyoko Watanabe, Yasushi Muraki, Takaaki Yokoyama and Masahiro Hoshino
doi: 10.1038/nature03573
First paragraph | Full Text | PDF (174K)
Letter: Detection of a radio counterpart to the 27 December 2004 giant flare from SGR 1806−20
P. B. Cameron, P. Chandra, A. Ray, S. R. Kulkarni, D. A. Frail, M. H. Wieringa, E. Nakar, E. S. Phinney, Atsushi Miyazaki, Masato Tsuboi, Sachiko Okumura, N. Kawai, K. M. Menten and F. Bertoldi
doi: 10.1038/nature03605
First paragraph | Full Text | PDF (217K) | Supplementary information
