The NASA Hubble Telescope was able to capture a cosmic event where a dead star has eaten an asteroid proven rich with water.
The dead star, called the GD 61, is 150 light years away from our planet but it provides an interesting insight to how things work in the cosmic system. According to the team of astronomers from the University of Cambridge, University of Warwick (U.K.) and University of Kiel (Germany), the dead star could explain how Earth has acquired masses of water on its surface. It may also give an idea of the future plight of the sun, Earth’s own bright star.
The research team found signs that show potential water abundance in the asteroid. They were also able to detect chemical elements such as magnesium, oxygen, silicon, and iron that are normally present in rock minerals. However, the most interesting element they found is oxygen.
The Hubble Telescope and Hawaiian Keck observatories found very high inflow of oxygen in the dead star. This could only be explained by the large asteroid carrying abundant water.
The researchers were able to see that the star has already burnt and spent its nuclear fuel leaving its surface glow weaker than before. Its gravity however is still forceful with the surrounding rocks crumbled and its fragments pulled into its surface.
It is possible that the GD 61 also had similar rocky planets like Earth before it died. "The reason that we can say that is that the planet-formation process starts with things as small as dust grains. They grow into things as big as pebbles and boulders and then as large as asteroids. Once you get to things as big as asteroids, planets are essentially inevitable - it's a runaway process; you simply cannot stop it," said lead researcher Dr Jay Farihi to BBC.
"So, we know there were rocky planets [in GD 61] because we can see the rocky building blocks; and we know there was the potential to deliver water to their surfaces because we've seen at least one very water-rich and large asteroid."
The dead star has 26 percent water while Earth only has 0.02 percent, both of which potentially came from fallen asteroids and comets.
The dead star’s water composition is comparable to Ceres, a huge asteroid found in the Solar System. It will soon be the subject of NASA’s space investigation in 2014.
The study was published in the Oct. 11 issue of the online magazine Science.