A team of astronomers announced on June 15 that they detected gaseous methyl alcohol or methanol in the TW Hydrae protoplanetary disc. This marks the first time for detecting the complex organic molecule in a young planet-forming disc.
The discovery of this methane derivative can provide additional information into how organic molecules are included into forming planets. Since methanol is considered to be a building block for many prebiotics, such as amino acid compounds, scientists say it will provide a glimpse into how life is formed in exoplanets.
“Methanol in gaseous form in the disc is an unambiguous indicator of rich organic chemical processes at an early stage of star and planet formation,” says co-author Ryan Loomis in a statement. “This result has an impact on our understanding of how organic matter accumulates in very young planetary systems.”
The methyl alcohol was formed on the disc’s small icy grains. This was then released in a gaseous form, forming a ring-like pattern close to the young star TW Hydrae.
The discovery was made possible through the Atacama Large Millimeter/Submillimeter Array in northern Chile. The protoplanetary disc, believed to be the closest known to Earth, is located about 170 light years away from us.
“Finding methanol in a protoplanetary disc shows the unique capability of ALMA to probe the complex organic ice reservoir in discs,” adds lead author, Catherine Walsh, from the Leiden Observatory in the Netherlands. “So, for the first time, allows us to look back in time to the origin of chemical complexity in a planet nursery around a young Sun-like star.”
The TW Hydrae protoplanetary disc is the perfect candidate to study discs in the universe. The team claims that its system resembles what our own solar system four billion years ago, during its formation.
Other compounds in the universe are formed by gas-phase chemistry or by the combination of both gas-phase and solid-phase. However, this methanol was formed in the ice phase in the coatings of small dust grains alone.