Resolved magnetic-field structure and variability near the event horizon of Sagittarius A*

  title={Resolved magnetic-field structure and variability near the event horizon of Sagittarius A*},
  author={Michael D. Johnson and Vincent L. Fish and Sheperd S. Doeleman and Daniel P. Marrone and Richard L. Plambeck and J. F. C. Wardle and Kazunori Akiyama and Keiichi Asada and Christopher Beaudoin and Lindy L. Blackburn and Raymond Blundell and Geoffrey C. Bower and Christiaan D. Brinkerink and Avery E. Broderick and Roger J. Cappallo and Andrew A. Chael and Geoffrey B. Crew and Jason Dexter and Matt Dexter and Robert W. Freund and Per Friberg and Roman Gold and Mark A. Gurwell and Paul T. P. Ho and Mareki Honma and Makoto Inoue and Michael Kosowsky and Thomas P. Krichbaum and James W. Lamb and Abraham Loeb and Ru-Sen Lu and David Macmahon and Jonathan C. McKinney and James M. Moran and Ramesh Narayan and Rurik A. Primiani and Dimitrios Psaltis and Alan E. E. Rogers and Katherine A. Rosenfeld and Jason SooHoo and Remo P. J. Tilanus and Michael Titus and Laura Vertatschitsch and Jonathan Weintroub and Melvyn C. H. Wright and K. H. Young and J. Anton Zensus and Lucy M Ziurys},
  pages={1242 - 1245}
Magnetic fields near the event horizon Astronomers have long sought to examine a black hole's event horizon—the boundary around the black hole within which nothing can escape. Johnson et al. used sophisticated interferometry techniques to combine data from millimeter-wavelength telescopes around the world. They measured polarization just outside the event horizon of Sgr A*, the supermassive black hole at the center of our galaxy, the Milky Way. The polarization is a signature of ordered… 

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