Stars forced to relocate near the Southern Fish

Mar 03, 2009
The three pictured galaxies -- NGC 7173 (middle left), NCG 7174 (middle right) and NGC 7176 (lower right) -- are part of the Hickson Compact Group 90, named after astronomer Paul Hickson, who first catalogued these small clusters of galaxies in the 1980s. NGC 7173 and NGC 7176 appear to be smooth, normal elliptical galaxies without much gas and dust. In stark contrast, NGC 7174 is a mangled spiral galaxy, barely clinging to independent existence as it is ripped apart by its close neighbors. The strong tidal interaction surging through the galaxies has dragged a significant number of stars away from their home galaxies. These stars are now spread out, forming a tenuous luminous component in the galaxy group. Credit: NASA, ESA and R. Sharples (University of Durham, U.K.)

About 100 million light-years away, in the constellation of Piscis Austrinus (the Southern Fish), three galaxies are playing a game of gravitational give-and-take that might ultimately lead to their merger into one enormous entity.

A new image from the Advanced Camera for Surveys on the NASA/ESA Hubble Space Telescope allows astronomers to view the movement of gases from galaxy to galaxy, revealing the intricate interplay among them.

The three pictured galaxies — NGC 7173 (middle left), NCG 7174 (middle right) and NGC 7176 (lower right) — are part of the Hickson Compact Group 90, named after astronomer Paul Hickson, who first catalogued these small clusters of galaxies in the 1980s. NGC 7173 and NGC 7176 appear to be smooth, normal elliptical galaxies without much gas and dust.

In stark contrast, NGC 7174 is a mangled spiral galaxy, barely clinging to independent existence as it is ripped apart by its close neighbours. The strong tidal interaction surging through the galaxies has dragged a significant number of stars away from their home galaxies. These stars are now spread out, forming a tenuous luminous component in the galaxy group.

Ultimately, astronomers believe that the stars in NGC 7174 will be redistributed into a giant 'island universe', tens to hundreds of times as massive as our own Milky Way.

Source: ESA/Hubble Information Centre

Explore further: How baryon acoustic oscillation reveals the expansion of the universe

add to favorites email to friend print save as pdf

Related Stories

Violent origins of disc galaxies probed by ALMA

18 hours ago

For decades scientists have believed that galaxy mergers usually result in the formation of elliptical galaxies. Now, for the the first time, researchers using the Atacama Large Millimeter/sub-millimeter ...

Astronomers unveil secrets of giant elliptical galaxies

Sep 12, 2014

New findings of how giant elliptical galaxies move have been discovered by an international team of astronomers using the newly installed Multi Unit Spectroscopic Explorer (MUSE) at the European Southern Observatory's (ESO) ...

Recommended for you

The Great Cold Spot in the cosmic microwave background

Sep 19, 2014

The cosmic microwave background (CMB) is the thermal afterglow of the primordial fireball we call the big bang. One of the striking features of the CMB is how remarkably uniform it is. Still, there are some ...

Mystery of rare five-hour space explosion explained

Sep 17, 2014

Next week in St. Petersburg, Russia, scientists on an international team that includes Penn State University astronomers will present a paper that provides a simple explanation for mysterious ultra-long gamma-ray ...

User comments : 0