We have launched the new Spitzer Space Telescope web site in beta at http://spitzer.caltech.edu. Let us know what you think! Send feedback to help@spitzer.caltech.edu
Frame Frame Frame Frame Frame
Frame Frame Frame Frame Frame
Frame Frame
NASA Spitzer Space Telescope • Jet Propulsion Laboratory
• California Institute of Technology
• Vision for Space Exploration
Frame Frame
Frame Frame Frame Frame Frame
Frame Frame Frame Frame Frame
Frame Frame Spitzer Newsroom Frame Frame
Frame Frame Frame Frame Frame
Frame Frame
 
Press Releases
 
— Chronological
 
— By Subject
 
— Outside Institutions
 
 
What's Happening Archive
 
 
Visuals
 
— Image Use Policy
 
 
Update Notifications
 
— Mailing List
 
— RSS Feed (XML)
 
 
References
 
— Fast Facts
 
— Press Kit (.pdf)
 
— Fact Sheet (.pdf)
 
— Field Guides
 
— Glossary
 
 
Media Contacts
 

Spitzer Exposes Our Galaxy's Deepest Secrets

GLIMPSE
New star cluster found by GLIMPSE
Credit: NASA/JPL-Caltech/E. Mercer (Boston University)

Written by Linda Vu, Spitzer Science Center
December 12, 2005

Astronomers have at last found inner light! Only, they didn't find it through the typical Earthly methods of meditation, exercise and therapy. Instead, the light was discovered inside our Milky Way galaxy after hours of deep self-reflection with NASA's Spitzer Space Telescope.

The astronomers, who are members of the Galactic Legacy Infrared Mid-Plane Survey Extraordinaire (GLIMPSE) team, used Spitzer's heat-seeking infrared eyes to gaze at the dust-drenched plane of our galaxy. When they did this, the galaxy's obscuring clouds of gas and dust became transparent, revealing approximately 100 new star clusters, each containing tens to hundreds of stars.

According to lead investigator Emily Mercer, a graduate student at Boston University, Mass., the new clusters will tell astronomers a great deal about the structure of the Milky Way and star formation within the galaxy.

"These little guys were quite hard to find," said Mercer. "The discovery required sophisticated computer sifting of GLIMPSE data and careful inspection of the Spitzer images."

In the past, our galaxy wasn't so quick to give up its stellar secrets. Because we sit inside its flat, spiral disk, most of the galaxy appears as a thick blurry band of light that stretches across the sky. Many of the stars in this galactic plane cannot be detected with visible-light or ultraviolet telescopes. That's because the cool clouds of dust and gas that hover around the galaxy's center and make up galactic spiral arms block their starlight from our view.

Two-thirds of the new star clusters were discovered through a computer method developed by Mercer and her advisor, Dr. Dan Clemens, also of Boston University. They used an algorithm to automatically sift through the GLIMPSE data for clusters. The rest were found using the traditional method of visually scrutinizing images for star clusters.

Mercer also found that there are nearly twice as many star clusters in the southern galactic plane, the portion of the galactic plane visible from the Earth's southern hemisphere, as in the northern galactic plane. She suspects that this observation may help astronomers map the location of the Milky Way's spiral arms.

"Emily has done a great job," says Clemens. "Her computer method for finding clusters has proved to be the most successful automated effort to date."

Both Clemens and Mercer are members of the multi-institutional GLIMPSE team, which is led by Dr. Edward Churchwell of the University of Wisconsin, Madison. The group was selected to survey the galactic plane with Spitzer's infrared array camera in November 2000 as part of Spitzer's Legacy program. So far, more than 30 million stars in the inner Milky Way have already been catalogued by GLIMPSE, and the team expects to identify more than 50 million stars by the end of the project.

"By making the galactic plane transparent, Spitzer opens a new door for astronomers to study the Milky Way," says Churchwell. "Some of the most interesting science likely to come out of this project will be serendipitous discoveries, which will open up entirely new avenues of inquiry."



The Spitzer Space Telescope is a NASA mission managed by the Jet Propulsion Laboratory. This website is maintained by the Spitzer Science Center, located on the campus of the California Institute of Technology and part of NASA's Infrared Processing and Analysis Center. Privacy Policy

Frame Frame
Frame Frame Frame Frame Frame
Frame Frame Frame Frame Frame