Astronomers report they have found water in a galaxy 11 billion light-years from Earth, the most distant water ever detected.
Until now, the farthest water ever found was glimpsed about 7 billion light-years from Earth. The new discovery suggests that water was common in galaxies in the early universe. We can see parts of such galaxies when we look at objects so distant that their light has taken billions of years to reach us.
Astronomers used the 100-meter radio telescope in Effelsberg, Germany, and the Very Large Array (VLA) in New Mexico to detect the chemical signature of water molecules in a galaxy called MG J0414+0534. The water molecules seem to be located in the galaxy's center, where a supermassive black hole called a quasar is spewing out tons of radiation as material falls into it. The water molecules lie in clouds of dust and gas that feed the black hole, and appear to be amplifying radio waves at a specific frequency, forming what's called a "maser," or the radio equivalent of a laser.
Though finding water in a distant galaxy doesn't tell us whether planets in that galaxy also have water, when searching for hints of life beyond Earth, it's always a good sign to find life's favorite molecule.
The galaxy is so far away, we see it as it was when the universe was roughly one-sixth its current age. At this distance, it would normally be too dim to see, if it weren't for the help of a cosmic magnifying glass called a gravitational lens. This trick of gravity, first predicted by Einstein, occurs when a massive foreground galaxy between Earth and a distant object bends the light of what lies behind it, creating multiple magnified images of the distant object so that we can see it.
"We were only able to discover this distant water with the help of the gravitational lens," Violette Impellizzeri, an astronomer at the Max-Planck Institute for Radioastronomy in Bonn, Germany, said in a press release. "This cosmic telescope reduced the amount of time needed to detect the water by a factor of about 1,000."
The finding, published Wednesday in the journal Nature, shows that the conditions necessary for water molecules to form and survive already existed only 2.5 billion years after the Big Bang.
"Because water masers arise close from the cores of galaxies, our result opens new interesting possibilities for studying supermassive black holes at a time when galaxies were forming," Impellizzeri said. "It will also generate further searches for water in other distant galaxies with the telescopes we have at our disposal today and with the next generation of radio telescopes; we now know water is out there."
Citation: "A gravitationally lensed water maser in the early Universe," C.M. Violette Impellizzeri, John P. McKean, Paola Castangia, Alan L. Roy, Christian Henkel, Andreas Brunthaler, & Olaf Wucknitz, 2008, Nature (18 December issue).
See Also:
- Water Vapor Confirmed on Alien Planet
- Water Found on the Moon
- Huge Buried Water Glaciers Discovered on Mars
Graphics: Milde Science Communication.
Background Image: HST Archive data, Inset: CFHT, J.-C.
Cuillandre, Coelum.
