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Hubble captures epic view of three galaxies merging into one

This week’s image from the Hubble Space Telescope shows no less than three galaxies that are in the process of merging to become one, called IC 2431. Located 681 million light-years away in the constellation of Cancer, this object shows what can happen when galaxies collide and merge into each other.

The enormous gravitational forces of such a merger pull the galaxies into elongated shapes, though the process isn’t entirely destructive — there is also plentiful star formation happening in parts of the merger, with new stars being born amid the chaos. Some of the most active areas may be right in the middle of the merger, though this can’t be seen in the image as a thick cloud of dust obscures the center.

A mass of dust and bright swirls of stars in this image are the distant galaxy merger IC 243.
The mass of dust and bright swirls of stars in this image are the distant galaxy merger IC 2431, which lies 681 million light-years from Earth in the constellation Cancer. The NASA/ESA Hubble Space Telescope has captured what appears to be a triple galaxy merger in progress, as well as a tumultuous mixture of star formation and tidal distortions caused by the gravitational interactions of this galactic trio. A thick cloud of dust obscures the center of this image – though light from a background galaxy is piercing its outer extremities. ESA/Hubble & NASA, W. Keel, Dark Energy Survey, Department of Energy, Fermilab, Dark Energy Survey Camera, (DECam), Cerro Tololo Inter-American Observatory, NoirLab/National Science Foundation/AURA, Sloan Digital Sky Survey; Acknowledgment: J. Schmidt

A notable fact about this object is that it was investigated using one of the earliest and biggest citizen science projects in astronomy. The Galaxy Zoo project, beginning in 2007, is now on its 15th version and has brought together members of the public to help identify and classify galaxies, mergers, and supernovas.

“The original Galaxy Zoo project was the largest galaxy census ever carried out and relied on crowdsourcing time from more than 100,000 volunteers to classify 900,000 unexamined galaxies,” Hubble scientists write. “The project achieved what would have been years of work for a professional astronomer in only 175 days and has led to a steady stream of similar astronomical citizen science projects. Later Galaxy Zoo projects have included the largest ever studies of galaxy mergers and tidal dwarf galaxies, as well as the discovery of entirely new types of compact star-forming galaxies.”

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Georgina Torbet
Georgina is the Digital Trends space writer, covering human space exploration, planetary science, and cosmology. She…
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