Paris (ANTARA News) - Astronomers poring over a young star 180 light years from Earth have found evidence that stellar birth can lead to the formation of a planet only millions of years later, a mere blink on the cosmic timescale.
The mainstream theory is that planets are forged from a disc of gas and dusty debris that is left over from the creation of a star.
How long this process takes is a matter of debate, though.
Earth is believed to be about 4.5 billion years old, and the Sun around 100 million years older.
But observations of some exoplanets -- planets in solar systems other than our own -- suggest the timescale could be much shorter, especially when it comes to the formation of gas giants rather than rocky planets like Earth.
A team led by Johny Setiawan, an Indonesia-born astronomer at the Max Planck Institute in Heidelberg, Germany, found a massive gas giant, between 5.5 and 13.1 times the size of Jupiter, orbiting within the dust disc of a well-studied star called TW Hydrae.
It takes a mere three and a half Earth days to zip around the star, at a distance of just 600,000 kilometres (375,000 miles).
Light from the star suggests that it is between only eight and 10 million years old, which implies that planets can form even before the disc has been dissipated by stellar particles and radiation.
Exoplanets were first spotted in 1995.
So far, 270 of them have been spotted, according to the Extrasolar Planets Encyclopaedia (http://exoplanet.eu/). Virtually all of the discoveries have been made indirectly, mainly by a "wobble" in light, seen from Earth, when the planet swings around its star.
The study appears Thursday in the British journal Nature. (*)
The mainstream theory is that planets are forged from a disc of gas and dusty debris that is left over from the creation of a star.
How long this process takes is a matter of debate, though.
Earth is believed to be about 4.5 billion years old, and the Sun around 100 million years older.
But observations of some exoplanets -- planets in solar systems other than our own -- suggest the timescale could be much shorter, especially when it comes to the formation of gas giants rather than rocky planets like Earth.
A team led by Johny Setiawan, an Indonesia-born astronomer at the Max Planck Institute in Heidelberg, Germany, found a massive gas giant, between 5.5 and 13.1 times the size of Jupiter, orbiting within the dust disc of a well-studied star called TW Hydrae.
It takes a mere three and a half Earth days to zip around the star, at a distance of just 600,000 kilometres (375,000 miles).
Light from the star suggests that it is between only eight and 10 million years old, which implies that planets can form even before the disc has been dissipated by stellar particles and radiation.
Exoplanets were first spotted in 1995.
So far, 270 of them have been spotted, according to the Extrasolar Planets Encyclopaedia (http://exoplanet.eu/). Virtually all of the discoveries have been made indirectly, mainly by a "wobble" in light, seen from Earth, when the planet swings around its star.
The study appears Thursday in the British journal Nature. (*)
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