|
|
Research ArticlesDetection of the Intrinsic Size of Sagittarius A* Through Closure Amplitude Imaging
We have detected the intrinsic size of Sagittarius A*, the Galactic center radio source associated with a supermassive black hole, showing that the short-wavelength radio emission arises from very near the event horizon of the black hole. Radio observations with the Very Long Baseline Array show that the source has a size of 24 ± 2 Schwarzschild radii at 7-millimeter wavelength. In one of eight 7-millimeter epochs, we also detected an increase in the intrinsic size of
1 Astronomy Department and Radio Astronomy Laboratory, University of California, Berkeley, CA 94720, USA. . These observations place a lower limit to the mass density of Sagittarius A* of 1.4 x 104 solar masses per cubic astronomical unit.
2 Radio Observatory Westerbork, ASTRON, Post Office Box 2, 7990 AA Dwingeloo, Netherlands. 3 Astronomy Department, University of Nijmegen, Postbus 9010, 6500 GL Nijmegen, Netherlands. 4 Max Planck Institut für Radioastronomie, Auf dem Hügel 69, D-53121 Bonn, Germany. 5 Department of Astronomy, Columbia University, Mail Code 5246, 550 West 120th Street, New York, NY 10027, USA. 6 Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, MS 78, Cambridge, MA 02138, USA. 7 National Radio Astronomy Observatory, Array Operations Center, Post Office Box O, Socorro, NM 87801, USA. * To whom correspondence should be addressed. E-mail: gbower{at}astro.berkeley.edu
The editors suggest the following Related Resources on Science sites:In Science Magazine
|
Science. ISSN 0036-8075 (print), 1095-9203 (online)
News | Science Journals | Careers | Blogs and Communities | Multimedia | Collections | Help | Site Map | RSS
Subscribe | Feedback | Privacy / Legal | About Us | Advertise With Us | Contact Us
© 2004 American Association for the Advancement of Science. All Rights Reserved.
AAAS is a partner of HINARI, AGORA, PatientInform, CrossRef, and COUNTER.
You have reached the bottom of the page. Back to top