Hubble camera detects farthest, oldest celestial bodies
UA scientists are using images captured by the Hubble telescope to decipher the history of the Milky Way and the universe.
The Hubble deep-space camera NICMOS has provided pictures of galaxies never seen before that may be more than 10 billion years old.
"The objects may be the farthest away and oldest that we have ever seen," said Rodger Thompson, a University of Arizona astronomy professor and principal investigator of the NICMOS team.
Studying those "early epic" galaxies may help researchers write a complete galactic history.
"Our only chance of understanding (galaxy formation) is to look back very far in time," said Dave Leckrone. a Hubble project researcher.
By looking at images from galaxies of sundry ages, astronomers can piece together a history of how the Milky Way may have come into existence.
"Hopefully we are seeing snapshots of how the Milky Way has formed," said Marcia Rieke, an investigator on the NICMOS team.
There are various theories describing how clouds of gas and dust coalesce into complex systems of stars and planets, Thompson said.
He and his team hope to use images of distant galaxies to figure out how the Milky Way and other galaxies formed. They can gauge age and distance of the galaxies through data from NICMOS.
Until the most recent NICMOS images were captured, there were two theories of galactic formation. One is that clouds of matter, with about 100 billion times the mass of the sun, come together and form stars. Others speculate the reverse - that galactic formation happens after irregularly shaped clouds of cosmic dust have already developed stars.
The Hubble camera has identified bright spots in galaxies previously thought to be odd dust clouds. The bright spots occur in places where new stars are being generated, Thompson said.
His next task will be to calculate the exact distance of the newfound galaxies by interpreting infrared data. As the universe expands and objects move away from Earth, they appear red. By studying that phenomenon, astronomers can date celestial objects by determining distance.
Thompson said some stars generated in early epic galaxies may be the first ever created in the universe. If those stars can be dated, they will give researchers some information about the age of the universe.
"We may be seeing them (first generation stars) right now in these early-epic galaxies," Thompson said, but added that scientists may not know until the Next Generation Telescope is launched in 2007.
Sarah Spivack can be reached via e-mail at Sarah.Spivack@wildcat.arizona.edu.