Colliding galaxies make love, not war

Oct 17, 2006
Colliding Galaxies Make Love, Not War
This Hubble image of the Antennae galaxies is the sharpest yet of this merging pair of galaxies. As the two galaxies smash together, billions of stars are born, mostly in groups and clusters of stars. The brightest and most compact of these are called super star clusters. Credit: Credit: NASA, ESA, and B. Whitmore (Space Telescope Science Institute). Acknowledgement: James Long (ESA/Hubble).

A new Hubble image of the Antennae galaxies is the sharpest yet of this merging pair of galaxies. As the two galaxies smash together, billions of stars are born, mostly in groups and clusters of stars. The brightest and most compact of these are called super star clusters.

The Universe is an all-action arena for some of the largest, most slowly evolving dramas known to mankind. A new picture taken by the Advanced Camera for Surveys (ACS), onboard the NASA/ESA Hubble Space Telescope, shows the "best ever" view of the Antennae galaxies - seemingly a violent clash between a pair of once isolated galaxies, but in reality a fertile marriage. As the two galaxies interact, billions of stars are born, mostly in groups and clusters of stars. The brightest and most compact of these are called super star clusters.

The two spiral galaxies started to fuse together about 500 million years ago making the Antenna galaxies the nearest and youngest example of a pair of colliding galaxies. Nearly half of the faint objects in the Antennae are young clusters containing tens of thousands of stars. The orange blobs to the left and right of image centre are the two cores of the original galaxies and consist mainly of old stars criss-crossed by filaments of dark brown dust. The two galaxies are dotted with brilliant blue star-forming regions surrounded by pink hydrogen gas.

The image allows astronomers to better distinguish between the stars and super star clusters created in the collision of two spiral galaxies. The observations show that only about 10% of the newly formed super star clusters in the Antennae will live to see their ten millionth birthday. The vast majority of the super star clusters formed during this interaction will disperse, with the individual stars becoming part of the smooth background of the galaxy. It is however believed that about a hundred of the most massive clusters will survive to form regular globular clusters, similar to the globular clusters found in our own Milky Way galaxy.

The Antennae galaxies take their name from the long antenna-like "arms" extending far out from the nuclei of the two galaxies, best seen by ground-based telescopes. These "tidal tails" were formed during the initial encounter of the galaxies some 500 million years ago. The give us a preview of what may happen when our Milky Way galaxy likely collides with the neighbouring Andromeda Galaxy about 6 billion years from now.

Source: ESA/Hubble Information Centre

Explore further: Planck helps to understand the macrostructure of the universe

Related Stories

Far from home: Wayward cluster is both tiny and distant

Mar 03, 2015

Like the lost little puppy that wanders too far from home, astronomers have found an unusually small and distant group of stars that seems oddly out of place. The cluster, made of only a handful of stars, ...

Stars found forming at Milky Way's outer edge

Feb 27, 2015

Brazilian astronomers said Friday they had found two star clusters forming in a remote part of our Milky Way galaxy where such a thing was previously thought impossible.

The Milky Way's new companion galaxies

Mar 18, 2015

When we think of cosmology, we often imagine the largest telescopes peering into the deepest space, collecting the feeble light from exploding stars or the first galaxies.

Recommended for you

Image: The tumultuous heart of the Large Magellanic Cloud

21 hours ago

A scene of jagged fiery peaks, turbulent magma-like clouds and fiercely hot bursts of bright light. Although this may be reminiscent of a raging fire or the heart of a volcano, it actually shows a cold cosmic ...

Rocky planets may orbit many double stars

Mar 30, 2015

Luke Skywalker's home in "Star Wars" is the desert planet Tatooine, with twin sunsets because it orbits two stars. So far, only uninhabitable gas-giant planets have been identified circling such binary stars, ...

Is the universe finite or infinite?

Mar 27, 2015

Two possiblities exist: either the Universe is finite and has a size, or it's infinite and goes on forever. Both possibilities have mind-bending implications.

User comments : 0

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.