Looking up into the sky is like being in a time machine. Light traveling from the most distant stars and galaxies can take billions of years to reach Earth, so we see them now as they were a long, long time ago. With new telescopes and cameras, astronomers are looking farther back into the dim past than ever.
Two groups of scientists have glimpsed some of the most distant galaxies yet, giving new insights into what the universe was like soon after the Big Bang. "We are seeing some of the first galaxies to be born," says Richard G. McMahon of the University of Cambridge in England.
McMahon’s team looked at images taken with a special camera on the Hubble Space Telescope. The pictures showed six extremely distant galaxies, one as far as 12.7 billion light-years away, the researchers report.
The other team, led by Yoshiaki Taniguchi of Tohoku University in Sendai, Japan, went to Mauna Kea in Hawaii to look through the Subaru telescope, which measures about 25 feet across. They identified 73 galaxies. One turned out to be the most distant galaxy ever seen, at 12.8 billion light-years from Earth, the team reports.
Both groups noticed that the distant galaxies were much dimmer and less dense than similar, closer galaxies. Some scientists speculate that, early on, the universe was filled with smaller galaxies that merged to build the large ones we know today.—E. Sohn
Cowen, Ron. 2003. Once upon a time in the cosmos: Using distant galaxies to study the early universe. Science News 163(April 12):227-228.