The first images have been revealed from a telescope that can map the sky much faster and deeper than any other.
The Vista (Visible and Infrared Survey Telescope for Astronomy) is dedicated to mapping the sky in infrared light.
Spectacular images, including some of the centre of our Milky Way, show, astronomers say, that the UK-designed telescope is working "extremely well".
It is based at the European Southern Observatory's (ESO) Paranal Observatory in Chile.
When the UK was first negotiating to join ESO, Vista became an in-kind payment towards its subscription.
It was formally handed over to ESO at a ceremony in Garching, Germany on 10 December 2009.
Now that the telescope is up and running, its surveys will help astronomers to understand the nature and origin of stars and galaxies.
Professor Jim Emerson from Queen Mary, University of London led a consortium of 18 UK universities that conceived and developed Vista.
He said he was looking forward to a rich harvest of science from the new telescope and told BBC News that Vista could be "all things to all astronomers".
"It's going to be like building an Ordnance Survey map of the Universe - that people can use to search for many different things," he said.
"It will survey the geography of the Universe and, with its incredible power, pick out the locations of interesting objects, which were unknown."
Vista's super-sensitive infrared camera could also help uncover the relationship between the structure of the Universe and the mysterious "dark energy" and "dark matter".
These strange phenomena cannot be investigated directly; their properties can only be inferred from the position and movement of other detectable celestial objects.
So a more detailed map of the sky could help scientists to learn more about them.
By detecting infrared light, the telescope is able to see through the dust that can obscure galaxies.
It will also pick up the faint glow of extremely distant objects - light that has been stretched into longer infrared wavelengths by the expansion of the Universe.
Vista also has a large field of view, and can cover wide areas of sky quickly - each of its images captures an area of sky about ten times as large as the full Moon.
Professor Emerson said: "History has shown us that the most exciting things that come out of projects like Vista are what you least expect, and I'm very excited to see what these will be."
The UK's Minister of State for Science and Innovation Lord Drayson, said: "This outstanding example of UK kit is revealing our Universe's deepest secrets. I eagerly await more images from Vista."