Mergers and Acquisitions

NGC 2207 is a pair of colliding spiral galaxies. Although individual stars are too far apart to collide, the material between them combines to create high-density pockets of gas. Those, in turn, gravitationally collapse, triggering a firestorm of star birth. This galaxy collision will go on for several millions of years, leaving the galaxies’ shapes completely altered.

This animation combines data from three satellite observatories. Optical: Hubble data shows trails of stars and gas trace out spiral arms, stretched by the tidal pull between the galaxies. Infrared: Spitzer data reveals the glow of warm dust; raw material for the creation of new stars and planets. X-ray: Chandra view reveals areas of active star formation and the birth of super star clusters.

Video Credit: STScI

A Galactic Merger

ngc2207Over next couple of billion years, these two spiral galaxies will end up in a complete galactic merger—the two galaxies will become a single, larger one. They’re about 150 million light-years away in the constellation of Canis Major (the Great Dog). The gravitational attraction of NGC 2207, the larger of the pair, is already stirring things up throughout its smaller partner, distorting IC 2163’s shape and throwing stars and gas into long streamers that extend over 100,000 light-years. However, most of the space between stars in a galaxy is empty. When these galaxies collide, almost none of the stars in them will crash into another star.

Image Credit: ESO

An X-Ray View (And Infrared Too)

ngc2207_chandraA few weeks ago, I posted a Hubble image of two merging galaxies, NGC 2207 and IC 2163. This composite image of those galaxies contains Chandra x-ray data in pink, optical light data from the Hubble in red, green, and blue (appearing as blue, white, orange, and brown), and infrared data from the Spitzer Space Telescope in red.

Image Credit: NASA