Arp 274, NGC 5679
The Hubble images were created from HST data from proposals 11994: M. Livio (STScI), Z. Levay, L. Frattare, K. Noll, M. Mutchler, and W. Januszewski (Hubble Heritage Team/STScI).
F450W (B), F606W (V), F673N (redshifted H-alpha), and F814W (I)
The image is a composite of separate exposures made by the WFPC2 instrument on the Hubble Space Telescope. Three filters were used to sample broad wavelength ranges. One filter was used to sample narrowband emission. The color results from assigning different hues (colors) to each monochromatic image. In this case, the assigned colors are:
Red: F673N (redshifted H-alpha) + F814W (I)
Green: F606W (V)
Blue: F450W (B)