[Previous] | [Session 86] | [Next]
S. Horiuchi, D.L. Meier, R.A. Preston (Jet Propulsion Laboratory)
We conducted a VSOP monitoring program of Centaurus A, the nearest active galaxy, extensively at 5 GHz and 1.6 GHz on several different time scales during mid 1999 - mid 2000 when the uv-coverage was optimal. Space-ground baseline fringes of Centaurus A were detected for the first time, although the signal to noise ratio became rapidly smaller as the space baseline length became larger than one Earth diameter. These observations produced images of the sub-parsec jet components with a resolution several times better than images in an ongoing extensive 8.4 GHz monitoring campaign and few times better than the 22 GHz studies. Owing its proximity, our Cen A space-VLBI images are some of the highest spatial resolution images ever made - 0.008 pc per beam – only comparable to the Junor et al. 43 GHz VLBI images of M87. High performance of ground array enabled us to image the Cen A counter jet at 5 GHz for the first time. We discuss the implication of the complex behavior of the sub-parsec jet flow, the environment of the central engine, and the possibility to test theoretical models for the differences between Fanaroff & Riley classes I and II.
We gratefully acknowledge the VSOP Project, which is led by the Japanese Institute of Space and Astronautical Science in cooperation with many organizations and radio telescopes around the world. S.H. acknowledges support through an NRC/NASA-JPL Research Associateship.
[Previous] | [Session 86] | [Next]
Bulletin of the American Astronomical Society, 34, #4
© 2002. The American Astronomical Soceity.