Scientists for the first time have detected water vapor in a shadowy, dusty disk around a young star, NASA said in a statement.
The data suggests the disk, that is poised to develop into a solar system, contains great quantities of water. This is evidence of the possibility of there being many water-covered planets like Earth in the universe. The discovery was made by the European Space Agency's Herschel Space Observatory.
It's not the first time astronomers have found warm water vapor in planet-forming disks close to a star. Those discoveries did not, however, find evidence for vast quantities of water extending out into the cooler, far reaches of disks where comets take shape, until now. The more water in disks for icy comets to form, the greater the chances that large amounts eventually will reach new planets through impacts.
"Our observations of this cold vapor indicate enough water exists in the disk to fill thousands of Earth oceans," astronomer Michiel Hogerheijde of Leiden Observatory in The Netherlands said. Hogerheijde is the lead author of a paper describing these findings in the Oct. 21 issue of the journal Science.
The star is called TW Hydrae. It's 10 million years old and is about 175 light-years away from Earth, in the constellation Hydra. The frigid watery mist detected by Hogerheijde and his team is thought to originate from ice-coated grains of dust near the disk's surface. Ultraviolet light from the star causes some water molecules to break free of this ice, creating a thin layer of gas with a light signature detected by Herschel's Heterodyne Instrument for the Far-Infrared, or HIFI.
TW Hydrae is an orange dwarf star, somewhat smaller and cooler than our yellow-white sun. The dusty disk that encircles the star has a size nearly 200 times the distance between Earth and the sun. Over the next few million years, astronomers believe matter within the disk will collide and grow into planets, asteroids and other heavenly bodies. Dust and ice particles will assemble as comets.
Tell us in the comments if you think this is evidence of many water-covered planets in the universe.