Distant interacting galaxies – located 23 million light-years away – bear an uncanny resemblance to a penguin guarding an egg.
February 01 | 2018
The “penguin” part of the pair was probably once a relatively normal-looking spiral galaxy, flattened like a pancake with smoothly symmetric spiral arms. Rich with newly-formed hot stars, seen in visible light as bluish filaments, its shape has now been twisted and distorted as it responds to the gravitational tugs of its neighbor. The “egg” of the pair is distinctly different with its greenish glow, which tells the story of a population of much older stars. The absence of glowing red dust features informs us that it has long since lost its reservoir of gas and dust from which new stars can form. Eventually these two galaxies will merge to form a single object, with their two populations of stars, gas and dust intermingling. This kind of merger was likely a significant step in the history of most large galaxies we see around us in the nearby universe, including our own Milky Way. Data from our Spitzer and Hubble (@NASAHubble) space telescopes have been combined to show these dramatic galaxies in light that spans the visible and infrared parts of the spectrum. Credit: NASA-ESA/STScI/AURA/JPL-Caltech