IC 4970

IC 4970 is an unbarred lenticular galaxy of type SA0^- pec: in the constellation Pavo. It is 212 e6ly from Earth and is interacting with the barred spiral galaxy NGC 6872. It was discovered on 21 September 1900 by American astronomer DeLisle Stewart.

Interaction with NGC 6872


IC 4970 is located a few arcseconds away from the much larger barred spiral galaxy NGC 6872, and the two are known to be interacting with each other. Horrelou and Koribalski (2007) reported on a computer simulation used to determine how the two galaxies were interacting. The study concluded that IC 4970 approached NGC 6872 nearly along the plane of its spiral disk, making a closest approach approximately 130 million years ago resulting in the latter's current highly elongated shape.

An ultraviolet-to-infrared study by Eufrasio, et al. (2013), using data from GALEX, Spitzer, and other resources found that the interaction between the two galaxies appears to have triggered significant star formation in the northeastern arm of NGC 6872 beginning about 40 kpc from its nucleus. The same appears to have also occurred in the southwestern arm. A bright ultraviolet source was discovered at the end of the northeastern arm, around 90 kpc from the nucleus, which may be a tidal dwarf galaxy formed out of the interaction between IC 4970 and NGC 6872. The bright ultraviolet nature of this cluster indicates that it contains stars less than 200 million years old, which roughly coincides with the timeframe of the collision.