Oceans of water vapour found in disc around Sun-like star HL Tauri

Using the Atacama Large Millimeter/submillimeter Array (ALMA), astronomers have found water vapour in the disc around a young Sun-like star exactly where planets may be forming.

The observations from ALMA reveal that the inner disc of HL Tauri, a star-forming region located 450 light-years away from Earth in the constellation Taurus, has at least three times as much water as in all of Earth's oceans.

"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." says Stefano Facchini, an astronomer at the University of Milan, Italy, who led the study published today in Nature Astronomy.

A substantial quantity of water vapour was found in the region where a known gap in the HL Tauri disc exists, where a planet could potentially be forming. This suggests that the water vapour could affect the chemical composition of planets forming in those regions.

"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," Facchini added.

📣 New discovery! @almaobs , in which ESO is a partner, has found oceans of water vapour in the disc around the Sun-like star HL Tauri 🌟, revealing a new link between water and planet formation. 1/Read more: https://t.co/rxX7lI6D3e📷 ALMA (ESO/NAOJ/NRAO)/S. Facchini et al. pic.twitter.com/FfSKSAwO2q

— ESO (@ESO) February 29, 2024

The Atacama Large Millimeter/submillimeter Array is an international astronomy facility designed to study light from some of the coldest objects in the Universe. Located some 50 km east of San Pedro de Atacama in northern Chile, the observatory comprises 66 high-precision antennas, spread over distances of up to 16 kilometres.

With a vision up to ten times sharper than the NASA/ESA Hubble Space Telescope, ALMA can probe the Universe at millimetre and submillimetre wavelengths with unprecedented sensitivity and resolution.