A team of astronomers has detected for the first time,around a nascent solar system, aextensive water vapor cloudcold enough for the formation of kites thatcould deposit oceans on dry planets. It lies within the planet-forming disk surrounding the star TW Hydrae, 176 light-years away in the constellation Hydra, and containsvolumes of water equivalent to thousands of the earth’s oceans. In fact, this star would be the center of the potential solar system closest to Earth. Details are published in the magazineScience.
Ted Bergin of the University of Michigan and his colleagues used the Heterodyne Instrument for Extreme Infrared (HIFI) from theHerschel Space Observatory, in orbit, to detect the chemical signal of the water. Scientists had previously found warm water vapor in the planet-forming disks closest to the central star. But, until now, no evidence has been found that the vast amounts of water extended to the colder and farthest regions of the disks, where comets and giant planets take shape. The more water is available in the disks for icy comets to form, the greater the chances that large amounts of water will reach new planets through impacts.
“The finding tells us thatthe materials that life needs are present in a system before planets are born“says Bergin.” We expected it to be so, but now we know that it is because we have detected it directly. I mean, we can see it. “
Other recent discoveries made with HIFI support the theory that comets carried a significant portion of the oceans on Earth. The researchers determined that the ice on a comet namedHartley 2it has the same chemical composition as our oceans.
Herschel, a mission of the European Space Agency (ESA) with NASA participation, is an orbital telescope that allows astronomers to observe images at extreme infrared wavelengths where organic molecules and water emit their chemical signals.
