Research Article

Detection of the Intrinsic Size of Sagittarius A* Through Closure Amplitude Imaging

See allHide authors and affiliations

Science  30 Apr 2004:
Vol. 304, Issue 5671, pp. 704-708
DOI: 10.1126/science.1094023

You are currently viewing the abstract.

View Full Text

Log in to view the full text

Log in through your institution

Log in through your institution

Abstract

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 Math. These observations place a lower limit to the mass density of Sagittarius A* of 1.4 × 104 solar masses per cubic astronomical unit.

View Full Text