Mergers and Acquisitions


In this image, galaxy NGC 2799 appears to being pulled into the center of its neighbor NGC 2798. Interacting galaxies such as these may eventually merger or form a unique pairing. For now, stars from NGC 2799 seem to be falling into NGC 2798 almost like droplets of water.

Galactic mergers usually take place over time scales of several hundred million to a billion or more years. While one or both of the galaxies may cease to exist as an independent entity, the vast space between stars means that stellar collisions are unlikely, so the individual stars typically drift past each other. Our Milky Way is on track to merge with the Andromeda galaxy in four billion years or so.

Image Credit: NASA / ESA

A 3D View of a Galactic Merger


This animation shows a #D rendering of a gas halo observed by ESO’s Very Large Telescope superimposed over an older image of a galaxy merger obtained with ESO’s Atacama Large Millimeter Array. The halo of hydrogen gas is shown in blue, and the ALMA data is shown in orange. The halo is bound to the galaxy, which contains a quasar at its center. The gas in the halo provides the perfect food source for the supermassive black hole at the centre of the quasar.

The redshift on these objects is 6.2, meaning we see them as they were 12.8 billion years ago.

Video Credit: ESO