This new image from the Gemini South telescope in Chile captures a pair of galaxies locked in a graceful waltz that will eventually bring the two crashing together.

The telescope was aimed at these galaxies at the suggestion of a group of Australian students at the Sydney Girls High School Astronomy Club, who won a Gemini-sponsored contest searching for beautiful and scientifically useful images of the cosmos.

These galaxies are "more than just a pretty picture," the students wrote. The main galaxy, NGC 6872, is one of the largest barred spiral galaxies known, extending 700,000 light-years from tip to tip. Astronomers think the galaxy was stretched by the gravitational pull of its smaller companion, spiral galaxy IC 4970 (right).

Over the next few hundreds of millions of years, NGC 6872's spiral arms will collapse back into the galaxy's center, and IC 4970 will be swallowed up by its larger neighbor. Such cannibalism is common among galaxies. Our own Milky Way is in the process of devouring several of its smaller companions, and will eventually smash into and merge with the nearby spiral galaxy Andromeda.

Galactic collisions often trigger a burst of new star formation. The extended fingers of NGC 6872's spiral arms already display the blue light of young star clusters. The winning high schoolers suggested exploring these young stellar neighborhoods with color images from Gemini.

"If enough color data is obtained in the image it may reveal easily accessible information about the different populations of stars, star formation, relative rate of star formation due to the interaction, and the extent of dust and gas present in these galaxies," the students wrote.

When viewers consider this image "in contrast to their daily life," the students added, "there is a significant possibility of a new awareness or perception of the age and scale of the universe, and their part in it."

Image: Sydney Girls High School Astronomy Club, Travis Rector (University of Alaska, Anchorage), Ángel López-Sánchez (Australian Astronomical Observatory/Macquarie University), and the Australian Gemini Office.

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