Breakthrough in hunt for life beyond Earth after oceans of water found on planet forming star
Water has been found in deep space on a disc around a young star where planets may be forming.
Three times as much water as in all of Earth’s oceans has been found in the inner disc of the young Sun-like star HL Tauri.
HL Tauri sits around 450 light years away from Earth in the constellation Taurus.
The observations were made made using the Atacama Large Millimetre/submillimetre Array telescope (Alma).
This discovery forms a new link between the key ingredient for life and planet formation.
Before now researchers had not been able to map how water is distributed in a stable, cool disc – the disc type that offers the best conditions for planets to form around stars.
‘I had never imagined that we could capture an image of oceans of water vapour in the same region where a planet is likely forming,’ said Dr Stefano Facchini, an astronomer at the University of Milan, Italy, who led the study.
‘Our results show how the presence of water may influence the development of a planetary system, just like it did some 4.5 billion years ago in our own solar system.’
Co-author Leonardo Testi, an astronomer at the University of Bologna, Italy, said: ‘It is truly remarkable that we can not only detect, but also capture, detailed images and spatially resolve water vapour at a distance of 450 light-years from us.’
The observations with Alma, of which the European Southern Observatory (ESO) is a partner, allow astronomers to work out the distribution of water in different regions of the disc.
According to the study, published in Nature Astronomy, a significant amount of water was found in the region where a known gap in the HL Tauri disc exists.
Researchers say this suggests that this water vapour could affect the chemical composition of planets forming in those regions.
‘It is truly exciting to directly witness, in a picture, water molecules being released from icy dust particles,’ said Elizabeth Humphreys, an astronomer at ESO.
The dust grains that make up a disc are the seeds of planet formation, colliding and sticking together to become even larger bodies.
Astronomers believe that where it is cold enough for water to freeze onto dust particles, things stick together better, creating the ideal spot for planets to form.