Thursday, April 15, 1999 Published at 10:03 GMT 11:03 UK
Hubble spies most distant object
The galaxy was imaged in December 1997
The most distant known object in the Universe has been discovered by the Hubble Space Telescope.
It is a galaxy of stars. The light from this galaxy started its journey to Earth when the Universe was extremely young - just a 20th of its current age of about 13 billion years old.
Professor Kenneth Lanzetta and colleagues from the State University of New York at Stony Brook, New York, made the observation using an instrument on Hubble called the Space Telescope Imaging Spectrograph. This has the ability to study the light from very faint objects.
In technical terms, the galaxy has what is called a "redshift" of z = 6.68. The term redshift refers to the shifting of light to lower frequencies - the shift being greater with distance.
Shifted into the infrared
This is a consequence of the Doppler effect - as the Universe expands, progressively more distant objects appear to be moving faster and faster away from us.
The galaxy reported by Lanzetta and colleagues is so far away that ultraviolet light is shifted into the visible spectrum, and visible light is shifted into the infrared.
This latter factor makes distant galaxies very hard to see, because of the absorption of hydrogen clouds in space along the line of sight.
"The thing we've found most surprising about this particular galaxy is that it is unusually bright," Professor Lanzetta told the BBC.
"That seems to indicate to us is that the early Universe was an active place where galaxies were forming stars at a very high rate and this seems to point in the direction where galaxies were formed early and formed more vigorously than we'd previously believed."
"It basically bears most directly on the scenarios of how the galaxies that we see and know about us today came into being."
Hubble obtained the data in December 1997, but the analysis has only now been reported in the journal Nature.
Professor Lanzetta said there would undoubtedly be further discoveries of objects even further away in space than the galaxy just identified.
"We happen to have identified the galaxy that, so far, is the most distant galaxy known. But this galaxy is by no means unique. We found it in a tiny patch of sky and if we found one there must be many, many more."
He said the technology available to astronomers would gradually improve and this would allow us to see even earlier epochs.