A coalition of the cosmos came together to give us the best view yet of distant colliding galaxies. Astronomers used telescopes on Earth and in space along with the gravity of distant galaxies to capture the image.
The colliding galaxies known as H-ATLAS J142935.3-002836 is so far away, light was first emitting from the object when the universe was just half its current age.
How did astronomers manage to capture such a distant object? They used an effect called gravitational lensing. Light bends around distant objects such as galaxies and works pretty much like a magnifying glass.
The above image shows what looks like two disc-shaped galaxies colliding with each other. The diagonal Milky-Way looking band overlaid on top is actually a galaxy closer to us doing the gravitational lensing. Check out the diagram below to see exactly how gravitational lensing works.
“These chance alignments are quite rare and tend to be hard to identify,” Hugo Messias, the lead author of a study on the colliding galaxies, said in a press release. “But, recent studies have shown that by observing at far-infrared and millimetre wavelengths we can find these cases much more efficiently.”
Capturing the above image took a massive effort from several telescopes. These included the Hubble and Spitzer telescopes in space along with the ALMA in Chile, the Keck Observatory in Hawaii and the Very Large Array in New Mexico.
“With the combined power of Hubble and these other telescopes we have been able to locate this very fortunate alignment, take advantage of the foreground galaxy’s lensing effects and characterize the properties of this distant merger and the extreme starburst within it,” said co-author Rob Ivison of the European Southern Observatory.
Image credits: NASA/ESA/ESO/W. M. Keck Observatory/M. Kornmesser