Galaxies Don Mask of Stars in New Spitzer Image

Apr 26, 2006
Galaxies Don Mask of Stars in New Spitzer Image
In this new false-colored image from NASA's Spitzer Space Telescope, the mysterious blue eyes are actually starlight from the cores of two merging galaxies, called NGC 2207 and IC 2163. The mask is the galaxies' dusty spiral arms. Image credit: NASA/JPL-Caltech/Vassar

A pair of dancing galaxies appears dressed for a cosmic masquerade in a new image from NASA's Spitzer Space Telescope. The infrared picture shows what looks like two icy blue eyes staring through an elaborate, swirling red mask. These "eyes" are actually the cores of two merging galaxies, called NGC 2207 and IC 2163, which recently met and began to twirl around each other.

The "mask" is made up of the galaxies' twisted spiral arms. Dotted along the arms, like strings of decorative pearls, are dusty clusters of newborn stars. This is the first time that clusters of this type, called "beads on a string" by astronomers, have been seen in NGC 2207 and IC 2163.

"This is the most elaborate case of beading we've seen in galaxies," said Dr. Debra Elmegreen of Vassar College in Poughkeepsie, N.Y. "They are evenly spaced and sized along the arms of both galaxies."

Elmegreen is lead author of a paper describing the Spitzer observations in the May 1 issue of the Astrophysical Journal.

Astronomers say the beads were formed when the galactic duo first met. "The galaxies shook each other, causing gas and dust to move around and collect into pockets dense enough to collapse gravitationally," said Dr. Kartik Sheth of NASA's Spitzer Science Center at the California Institute of Technology in Pasadena. Once this material condensed into thick bead-like clouds, stars of various sizes began to pop up within them.

Spitzer's infrared camera was able to see the dusty clouds for the first time because they glow with infrared light. The hot, young stars housed inside the clouds heat up the dust, which then radiates at infrared wavelengths. This dust is false-colored red in the image, while stars are represented in blue.

The Spitzer data also reveal an unusually bright bead adorning the left side of the "mask." This dazzling orb is so packed full of dusty materials that it accounts for five percent of the total infrared light coming from both galaxies. Elmegreen's team thinks the central stars in this dense cluster might have merged to become a black hole.

Visible-light images of the galaxies show stars located inside the beads, but the beads themselves are invisible. In those pictures, the galaxies look more like a set of owl-like eyes with "feathers" of scattered stars.

NGC 2207 and IC 2163 are located 140 million light-years away in the Canis Major constellation. The two galaxies will meld into one in about 500 million years, bringing their masquerade days to an end.

Other authors of this research include Bruce Elmegreen of IBM Watson Research Center, Yorktown Heights, N.Y., Michele Kaufman of Ohio State University, Columbus; Curt Struck of Iowa State, Ames; Magnus Thomasson of Onsala Space Observatory, Sweden; and Elias Brinks of the University of Hertfordshire, United Kingdom.

Source: Jet Propulsion Laboratory, by Whitney Clavin

Explore further: The weird ways fire behaves in space (w/ Video)

Related Stories

'Map spam' puts Google in awkward place

7 hours ago

Google was re-evaluating its user-edited online map system Friday after the latest embarrassing incident—an image of an Android mascot urinating on an Apple logo.

Team develops faster, higher quality 3-D camera

7 hours ago

When Microsoft released the Kinect for Xbox in November 2010, it transformed the video game industry. The most inexpensive 3-D camera to date, the Kinect bypassed the need for joysticks and controllers by ...

Recommended for you

The weird ways fire behaves in space (w/ Video)

18 minutes ago

Light a match on earth and you can expect the flame to shoot up in a tapering bulb. But light that match in space and you might not even recognize the small, blue orb at the tip. That's because fire behaves ...

Brian Schmidt discusses the fast-firing universe

1 hour ago

In 1998, a team led by a former Harvard graduate student shocked the astrophysics world by publishing results that said the expansion of the universe, believed to be gradually slowing, was instead accelerating.

Birth of a radio phoenix

3 hours ago

Abell 1033 is a cluster of over 350 galaxies located about 1.7 billion light-years away. Collisions between galaxies in clusters are common events, and each merger heats and shocks the nearby gas. The rapidly ...

Liquid crystal bubble OASIS in space

15 hours ago

No matter how beautiful or crystal clear the bubbling waters of an oasis may be, they seldom lead to technology breakthroughs. Yet, NASA's OASIS investigation's bubbles may lead to an ocean of new improvements ...

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.