The new study by scientists at the Universities of Warwick and Cambridge, analyzed the dust and debris surrounding the white dwarf star GD 61 170 light-years away. Scientists believe the discovery of the remnants of a rocky world with huge amounts of water is the first time they have found these basic ingredients for life in one place outside the solar system.
Using observations obtained with the Hubble Space Telescope and the large telescopes of the W. M. Keck Observatory, they found an excess of oxygen-a chemical signature that indicates that the debris had once been part of a bigger body originally composed of 26 percent water by mass.
By contrast, only approximately 0.023 percent of the Earth's mass is water.
The researchers suggest it is most likely that the water detected around the white dwarf GD 61 came from a minor planet at least 90 km in diameter but potentially much bigger, that once orbited the parent star before it became a white dwarf. In its former life, GD 61 was a star somewhat bigger than our Sun, and host to a planetary system, researchers said.
vidence for water outside our solar system has previously been found in the atmosphere of gas giants, but this study marks the first time it has been pinpointed in a rocky body, making it of significant interest in our understanding of the formation and evolution ofhabitable planets and life.
We know from our own solar system that the dwarf planet Ceres contains ice buried beneath an outer crust, and the researchers draw a parallel between the two bodies. Scientists believe that bodies like Ceres were the source of the bulk of our own water on Earth.
"The finding of water in a large asteroid means the building blocks of habitable planets existed-and maybe still exist-in the GD 61 system, and likely also around substantial number of similar parent stars," Lead author Jay Farihi, from Cambridge's Institute of Astronomy, said.
The study is published in the journal Science.
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