Planets Could Form In Less Than 1 Million Years, Evidence From Young Star Indicates

For the past many decades, scientists have believed that planets take at least tens of millions of years to form, gradually integrating from the rubble and dust that gathers around young stars. However, a new discovery may just challenge the existing theories and beliefs about the time taken for planet formations.

According to a report, in 2014 astronomers noticed a young star in the Taurus constellation, called HL Tauri, with inexplicable gaps in the clouds of dusts that surrounded it. The researchers observed the phenomenon after studying an image taken with the Atacama Large Millimeter/submillimeter Array (ALMA) located in Chile's Atacama Desert. On detailed observation, it was seen that there were gaps in the disk which led to a debate whether it indicated the presence of planets, and furthermore if planets could actually form in the young system that quickly. The discovery could not reach any conclusion, due to insufficient data supporting the theory at that point. Recently, however, new evidence has come to the forefront that supports the theory, i.e. the gaps are caused due to the presence of worlds.

On the basis of research, scientists have speculated that if planets did not cause the gap in the dust then the gas surrounding the stars too wouldn't have similar gaps in matching places. Incidentally, young stars' disks include dust and gas in the ratio 1:100. Subsequently, a team of researchers from Japan and Taiwan focused on the distribution of gas and discovered that the gaps in the gas matched the placing of the dust gaps. In addition, the gas density was found to be high enough to shelter a baby planet around the inner gap. "To our surprise, these gaps in the gas overlap with the dust gaps," said Dr Hsi-Wei Yen from Taiwan's Academia Sinica Institute of Astronomy and Astrophysics. "This supports the idea that the gaps are the footprints left by baby planets. Our results indicate that planets start to form much earlier than what we expected".

The new evidence of infant planets, as young as less than a million years, orbiting in a cloud of dust surrounding the HL Tauri has made scientists rethink the time duration taken by planets to form.  At the moment, the experts are conducting further researches before they can conclude whether the gaps noticed in the dust cloud are indeed because of a planet or simply due to a drag between the gas and dust particles. However, if the gap is caused by a planet, then that world would be more than two times the size of Jupiter.