Watery Asteroid Could Be Sign Of Habitable Exoplanets

The remains of a large, watery asteroid orbiting around a white dwarf star could mean that planets could have been capable of supporting life at one point.

The asteroid’s shredded remains were spotted by scientists using the Cosmic Origins Spectrograph, an instrument located on NASA’s Hubble Space Telescope, reports The Los Angeles Times.

The star, called GD 61, is about 150 light-years away from Earth and looked much like our sun before it collapsed about 200 million years ago.

However, the collapse created a white dwarf — an ultracompact object about the size of a planet.
While the star is interesting enough, study lead author Jay Farihi of Cambridge University, stated that the findings are also important, notes Space.com. He explained:

“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 a substantial number of similar parent stars.”

Farihi added, “These water-rich building blocks, and the terrestrial planets they build, may, in fact, be common — a system cannot create things as big as asteroids and avoid building planets, and GD 61 had the ingredients to deliver lots of water to their surfaces.”

Using the Cosmic Origins Spectrograph, the team saw magnesium, silicon, iron, and oxygen in the atmosphere of the white dwarf star. The elements are a clear indication that the star tore an asteroid to shreds. The amount of oxygen was so high that the team believes the asteroid was about 28 percent water, or about as wet as Ceres, a dwarf planet in Earth’s solar system.

It’s possible the asteroid was born from the destruction of a planet, but Farihi and his team believe it is more likely a building block that never turned in to an exoplanet. Farihi added, “That kind of rock together with water chemistry — like the Earth’s surface, basically — that has never been seen before.”

The technique used to identify the debris inside a white dwarf could be used in the future as scientists continue to look for habitable worlds and signs of life in the universe.

[Image via ShutterStock]