SourceEpochImageVisibility
1923+210
1997JAN11 2 GHz , 8 GHz 2 GHz , 8 GHz
1999APR15 2 GHz+ , 8 GHz+ 2 GHz+ , 8 GHz+
2001MAY09 2 GHz+ , 8 GHz+ 2 GHz+ , 8 GHz+
2004JUL14 2 GHz , 8 GHz 2 GHz , 8 GHz
2006JUL11 2 GHz+ , 8 GHz+ 2 GHz+ , 8 GHz+
2007AUG01 2 GHz+ , 8 GHz+ 2 GHz+ , 8 GHz+
2008JAN23 2 GHz+ , 8 GHz+ 2 GHz+ , 8 GHz+
2008MAY14 2 GHz+ , 8 GHz+ 2 GHz+ , 8 GHz+
2008SEP03 2 GHz+ , 8 GHz+ 2 GHz+ , 8 GHz+
A "+" after the frequency indicates VLBA+ observations.