The Hubble telescope has captured some of the oldest galaxies yet seen in the universe using a new infared camera, according to scientists in Britain.

The camera newly installed on the telescope by Nasa astronauts has snapped the galaxies "which are likely to be the most distant ever seen," said the scientists who studied the images.

The galaxies date back to when the universe was still in its infancy, less than one billion years after the Big Bang, they said.

The Wide Field Camera 3 uses infrared light, which is invisible to the human eye, with wavelengths about twice as long as visible light.

The highly sensitive camera can detect starlight from distant objects - light that has been "stretched" by the expanding universe.

"The expansion of the universe causes the light from very distant galaxies to appear redder, so having a new camera on Hubble which is very sensitive in the infrared means we can identify galaxies at much greater distances than was previously possible," said Stephen Wilkins, a postdoctoral researcher in astrophysics at Oxford University. The images were taken in a region of space called the Ultra Deep Field which was first captured by the Hubble and studied by scientists five years ago.

"Hubble has now revisited the Ultra Deep Field which we first studied five years ago, taking infrared images which are more sensitive than anything obtained before," said Daniel Stark, a postdoctoral researcher at the Institute of Astronomy in Cambridge who was involved in the work.

"We can now look even further back in time, identifying galaxies when the universe was only five percent of its current age - within one billion years of the Big Bang," he said on Britain's Royal Astronomical Society website.

The new camera was installed in May by Nasa spacewalking astronauts as part of a mission to upgrade and repair the 19-year-old telescope.

Two teams from the University of Oxford and the University of Edinburgh are set to publish their analysis in the Monthly Notices of the Royal Astronomical Society.