AAS 203rd Meeting, January 2004
Session 96 GALEX I: The Mission and Early Type Galaxies
Oral, Wednesday, January 7, 2004, 10:00-11:30am, Centennial III

[Previous] | [Session 96] | [Next]

[96.07] GALEX Wide-field Ultraviolet Imaging of NGC~5128 (Centaurus-A)

S.G. Neff (NASA/GSFC), D. Schiminovich, C. D. Martin (CIT), GALEX Science Team

We present new wide-field ultraviolet (UV) observations of the nearby active galaxy NGC~5128 (Centaurus A). The GALEX images provide 3\farcs5 - 5\farcs5 resolution over a 1.2 degree field, in two broad bands (1350-1800Å\ and 1800-3000Å, centered at 1550Å\ and 2200Å).

We detect ultraviolet emission associated with the radio and X-ray jets in both bands, extending out to a distance of ~40kpc from the galaxy nucleus. We compare the radio, X-ray, and UV jets, and discuss the feasibility of jet-induced star formation. We show how the UV emission relates to the optical filaments, HI and CO clouds, stellar shells, X-ray arcs, and young star chains previously reported by other authors.

In the central region of NGC~5128, we detect UV emission from young super-star-clusters and associated ionized gas located along the near edge and on the upper surface of the dusty warped disk. All of the UV emission in the galaxy appears to result from intense star formation in the disk; none appears to be associated with the old stellar population of the main galaxy body, and no UV emission from the AGN is detected. We estimate the numbers and ages of the massive young stars present, and the associated ionized gas masses.

Finally, we compare Cen-A to high redshift radio galaxies which were much more numerous in the earlier universe.

The GALEX satellite is a NASA Small Explorer, launched in April 2003. We gratefully acknowledge NASA's support for construction, operation, and science analysis for the GALEX mission.

[Previous] | [Session 96] | [Next]

Bulletin of the American Astronomical Society, 35#5
© 2003. The American Astronomical Soceity.