Nasa's Hubble Telescope shows images of 13 billion-year-old galaxies

The Hubble Space Telescope has peered back to a chaotic time 13.2 billion years ago when never-before-seen galaxies were tiny, bright blue and full of stars bursting to life all over the place.

Thanks to some complex physics tricks, Nasa's ageing telescope is just starting to see the universe at its infancy in living colour and detail.

Images released by the US space agency on Tuesday show galaxies that are 20 times fainter than those pictured before. They are from a new campaign to have the 23-year-old Hubble gaze much earlier and farther away than it was designed to see.

"I like to call it cosmic dawn," Hubble astronomer Jennifer Lotz said at the American Astronomical Society convention in Washington.

"It's when the lights are coming on."

It was a time when star formation was ramping up, and it was far more hectic than now.

"Imagine if you went back 500 million years after the big bang and looked around in the sky," astronomer Garth Illingworth of the University of California Santa Cruz said. "Galaxies are closer. They're smaller. They're bright blue and they're everywhere ...They are probably blobby, small, nothing like our Milky Way."