Astronomers spot most distant galaxies
The giant cities of stars appear as they were when the universe was just 500 million years old – little more than the blink of an eye since the Big Bang that created the cosmos. Their discovery will be announced today at a conference in London by Professor Richard Ellis, from the California Institute of Technology.
The galaxies were discovered with one of the most powerful telescopes in the world, the Keck II instrument on Hawaii, which acts as a 10-metre-wide eye on the sky. But they are so faint that they needed a natural “magnifying glass” deep in space to make them visible from Earth.
The light from the distant galaxies was magnified using a phenomenon called gravitational lensing. In other words, massive clusters of other galaxies lying between them and us warped and enhanced the light just like the lens on a telescope.
Professor Ellis said: “Gravitational lensing is the magnification of distant sources by foreground structures. By looking through carefully-selected clusters, we have located six star-forming galaxies seen at unprecedented distances, corresponding to a time when the Universe was only 500 million years old, or less than four per cent of its present age.”
Space observatory Spitzer has also been looking back to the early days of the universe, detecting light from the earliest objects within it.
Astronomers are now building telescopes on the ground and to fly in space to peer even further back to a time when the very first stars began to shine.
Photo: The picture shows how the six faint galaxies were revealed on the edge of giant clusters of galaxies closer to Earth.