The two spectacular interacting galaxies making up the pair known as Arp-Madore 608-333 seem to float side by side in this stunning image from the Hubble Space Telescope. Although they appear serene and unperturbed in this image, the two are subtly warping one another through a mutual gravitational interaction that is disrupting and distorting both galaxies. This drawn-out galactic interaction was captured by Hubble’s Advanced Camera for Surveys (ACS).
The interacting galaxies in Arp-Madore 608-333 were observed as part of an effort by astronomers to compile an archive of interesting targets for more detailed future study with Hubble, ground-based telescopes, and the NASA/ESA/CSA James Webb Space Telescope. Researchers scoured existing astronomical catalogs for a list of targets spread throughout the night sky to build up this archive. By so doing, they hoped to include cosmic objects that had already been identified as interesting and that would be easy for Hubble to observe no matter which direction it was pointing.
It is a drawn-out, competitive and difficult process to decide how to award NASA/ESA Hubble Space Telescope observing time, which is allocated so as to use every last second of Hubble time available. However, there is a small but persistent fraction of time — roughly 2–3% — that goes unused as Hubble turns to point at new targets. Snapshot programs, such as the one which captured Arp-Madore 608-333, exist to fill this gap and take advantage of any available moments between longer observations. As well as creating captivating images such as this, these snapshot programs enable scientists to gather as much astronomical data as possible with Hubble.