December 8, 2015

Galactic Gathering Gives Sparkling Light Display

NGC 2207 and IC 2163

This pair of spiral galaxies has been caught in a grazing encounter. NGC 2207 and IC 2163 have hosted three supernova explosions in the past 15 years and have produced one of the most bountiful collections of super-bright X-ray lights known. These special objects -- known as "ultraluminous X-ray sources" (ULXs) -- have been found using data from NASA's Chandra X-Ray Observatory.

This composite image of NGC 2207 and IC 2163 contains Chandra data in pink, optical-light data from NASA's Hubble Space Telescope visible-light data in blue, white, orange and brown, and infrared data from NASA's Spitzer Space Telescope in red.

Image Credit: NASA/CXC/SAO/STScI/JPL-Caltech
Explanation from:


  1. How do we know they are actually 'grazing'? The photo is in 2D and so how can we be sure they are not x amount of miles apart, one on 'top' of the other?