The discovery suggests that galaxies formed earlier than was once thought, as quasars are often associated with galaxies. Astronomers say the light emitted from the quasar was emitted just a billion years after the birth of the universe.

"Because we believe quasars are located in the cores of galaxies, this tells us an upper limit to the earliest time the galaxies formed," said Stephen Kent, head of the experimental astrophysics group at Fermi National Accelerator Laboratory, which participates in the SDSS. "As we discover quasars further away we now have evidence of galaxies forming earlier in the universe."

Objects moving away from the observer emit light whose wavelength is shifted toward the red end of the spectrum. An intensely strong red light signals that the object is moving away very quickly. The newly discovered quasar has a very high red shift, meaning that the light it emits has a wavelength that corresponds to the color red.

Astronomers extrapolate that objects moving away at high speed have been travelling at that accelerated speed since the birth of the universe and are thus very far away.

The Sloan Digital Sky Survey will continue searching the sky for distant objects. In all, it will survey a quarter of the night sky and investigate 200 million celestial objects.

SDSS is a project jointly conducted by the University of Chicago, Fermilab, the Institute for Advanced Study, and several other universities and government research agencies. NASA partially funds the project.

Xiohui Fan, an astronomer for the Sky Survey, spotted the quasar in observations made in March 2000.