NASA: GALEX Pinpoints Largest Spiral Galaxy – NGC 6872

Added by GM on January 11, 2013.
Saved under Jim Donahue, Science

A team of astronomers from the United States, Chile and Brazil have concluded that spiral galaxy NGC 6872 is the largest known spiral galaxy ever discovered.

This determination is based on archival data gathered by NASA’s Galaxy Evolution Explorer Mission, GALEX.

NASA’s Galaxy Evolution Explorer Mission has been on loan to the California Institute of Technology, Caltech, since May 2012.

NASA and Caltech signed a Space Act Agreement on May 14, 2012, allowing the University to resume spacecraft operations and data management for the mission using private funds.

“NASA sees this as an opportunity to allow the public to continue reaping the benefits from this space asset that NASA developed using federal funding,” said Peter Hertz, NASA’s Astrophysics Division director at the agency’s headquarters in Washington. “This is an excellent example of a public/private partnership that will help further astronomy in the United States.”

For the past decade, GALEX had been a NASA managed mission, searching the Galactic heavens and cataloging hundreds of millions of galaxies spanning more than 10 billion years of cosmic time.

“This mission was full of surprises and now more surprises are sure to come,” said Chris Martin, who will remain the mission’s principal investigator at Caltech. “It already has scanned a large fraction of the sky, improving our understanding of how galaxies grow and evolve. The astronomy community will continue those studies, in addition to spending more time on stars closer to home in our own galaxy.”

In the data analyzed by the team of astronomers was called from this previous decade of NASA managed administration of GALEX, in addition to findings from scientists at Caltech.

Measuring tip to tip across its two outsized spiral arms, NGC 6872 spans more than 522,000 light years, making it more than 5 times the size of our own Milky Way galaxy.

“Without GALEX’s ability to detect the ultraviolet light of the youngest, hottest stars, we would never have recognized the full extent of this intriguing system,” said lead scientist Rafael Eufrasio, a research assistant at NASA’s Goddard space flight Center in Greenbelt, Maryland., and a doctoral student at Catholic University of America in Washington.

The astronomers findings were presented yesterday at the American Astronomical Society meeting in Long Beach, California.

Caltech began to manage and operate the Galaxy Evolution Explorer Mission in early spring of last year, and along with several other international research groups, continues the missions objectives, which include ultraviolet studies of the universe, cataloging of galaxies, keeping track of how stars and galaxies change over time and making deep observation of the stars being surveyed for orbiting planets discovered by NASA’s Kepler mission.

“We’re thrilled that the mission will continue on its path of discovery,” said Kerry Erickson, the mission’s project manager at NASA’s Jet Propulsion Laboratory in Pasadena, California. “The galaxy evolution Explorer is like the ‘little engine that could,’ forging ahead into unexplored territory.”

NASA’s agreement would Caltech allows it to maintain ownership and liability for GALEX, and Caltech will then decommission the spacecraft for NASA when it completes its science discoveries activities.

GALEX is expected to remain in orbit for 66 more years, and will burn up upon reentry into the Earth’s atmosphere.

For a slideshow of images taken by GALEX, follow this link.

Article by Jim Donahue