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.
Since its detection in 2014, the brown dwarf known as WISE 0855 has fascinated astronomers. Only 7.2 light-years from Earth, it is the coldest known object outside of our solar system. Now, a team led by astronomers has succeeded in obtaining strong evidence for the existence of clouds of water or water ice — the first such clouds detected outside our solar system.
This Hubble image is of the peculiar galaxy NGC 1487, lying about 30 million light-years away. We are witnessing the possible merger of several dwarf galaxies into a new single galaxy. Its appearance is dominated by large areas of bright blue stars, illuminating the patches of gas that gave them life. This burst of star formation may well have been triggered by the merger.
The gravitational dance between two galaxies in our local neighbourhood has led to intriguing visual features in both as witnessed in this new NASA/ESA Hubble Space Telescope image. The tiny NGC 1510 and its colossal neighbour NGC 1512 are at the beginning of a lengthy merger, a crucial process in galaxy evolution.