Previous abstract Next abstract

Session 61 - New Views of the Magellanic Clouds.
Display session, Wednesday, June 12
Great Hall,

[61.12] NGC 4449: The Dr. Jekyll/Mr. Hyde of Magellanic Irregular Galaxies

E. M. Wilcots (U. Wisconsin), D. Hunter (Lowell Obs.), J. S. Gallagher (U. Wisconsin), H. van Woerden (Kapteyn Astronomical Inst.)

NGC 4449 is a nearby galaxy that has long been considered to be representative of normal giant Magellanic irregulars with an unusually large, quiescent disk. We present a VLA mosaic of the extended HI disk around NGC 4449 that shatters this preconception. Our data show NGC 4449 to contain a bright central condensation of gas associated with the optical galaxy. A long stream of gas emanates from the southern end of this condensation and curves 3/4 of the way around the galaxy. We estimate the total length of this arc to be \sim80 kpc. Additionally, a second streamer emanates from the northern end of the central condensation. While the morphology of the gas suggests that it has been disturbed by an external perturbation, it is dynamically cold and in regular rotation about the center of NGC 4449.

Program listing for Wednesday