The interacting galaxy pair NGC 5394/5 was first observed by William Herschel in 1787 using his 20-foot-long telescope. Since then, the galaxies, also known collectively as the Heron Galaxy thanks to their gravitationally distorted appearance, have become familiar targets for amateurs and professionals alike. This spectacular view was captured by the Gemini North 8-metre telescope in Hawaii using the Gemini Multi-Object Spectrograph. The four-colour composite image is the result of a 42-minute exposure. Astronomers believe the two galaxies have collided at least once before and are still engaged in a gravitational tug-of-war that will take millions of years to play out. Galactic collisions trigger star formation, visible in this image as reddish concentrations scattered throughout the larger galaxy (NGC 5395) and in the extended arms of the smaller companion (NGC 5394). Also known as Arp 84, the galaxy pair is located some 160 million light years from Earth in the constellation Canes Venatici.
The placid appearance of NGC 4889 can fool the unsuspecting observer. But the elliptical galaxy, pictured here in front of hundreds of background galaxies, and deeply embedded within the Coma galaxy cluster in this new image from the NASA/ESA Hubble Space Telescope, harbours a dark secret. At its heart lurks one of the most massive black holes ever discovered.
This curious galaxy — known by the seemingly random jumble of letters and numbers 2MASX J16270254+4328340 — has been captured by the NASA/ESA Hubble Space Telescope dancing the crazed dance of a galactic merger. The galaxy has merged with another galaxy leaving a fine mist, made of millions of stars, spewing from it in long trails.