Since its launch in 2021, the James Webb Space Telescope (JWST) has made some amazing discoveries. Recent observations have found a number of key ingredients required for life in young proto-stars where planetary formation is imminent. Chemicals like methane, acetic acid and ethanol have been detected in interstellar ice. Previous telescopic observations have only hinted at their presence as a warm gas. Not only have they been detected but a team of scientists have synthesised some of them in a lab.
These molecules found in the solid stage phase in young protostars are an indicator that the processes leading to formation of life may be more common than first thought. The complex organic molecules (COMs) were first predicted decades ago before space telescopes observations inconclusively identified them. A team of astronomers using the Mid-InfraRed Instrument (MIRI) on the JWST as part of the James Webb Observations of Young ProtoStars programme have identified the COMs individually.
One of the target objects observed as part of this study was IRAS 2A, a low mass protostar. The science team are particularly interested because the system has similar characteristics as our own star, the Sun. It gives us a great test bed to explore the processes of the Solar System and Earth’s development.
The presence in the solid phase and earlier detections in the gas phase suggests the process behind their existence is sublimation of ice. The process of sublimation is the transition straight from solid to gas without going through the liquid phase. The detection of COMs in ice suggests this is the origin of the COMs in gas.
The scientific community are now looking at the liklihood of transportation of the COMs to early planets as they form around the young stars. It is believed that their transportation as an ice are far more efficient to the protoplanetary disks than as a gas. It is quite likely that the icy COMs can be transported and inherited by comets and asteroids as the planets form. These new icy objects that develop can then, through their impacts, carry the complex molecules to planets, seeding them with the ingredients for life.
The team not only detected complex molecules, they also detected formic acid (the stuff that makes some insect bites sting), sulphur dioxide and formaldehyde. The sulphur dioxide was particularly useful since it allowed the team to calculate the deposits of oxidised sulphur as a function of emissions of the same. This is particularly of interest since it was pivotal in the development of metabolic reactions and processes in the young Earth.
A team from the University of Hawaii’s Department of Chemistry led by Professor Ralf I. Kaiser managed to synthesise a complex molecule known as Glyceric Acid. Understanding its formation process helps us to understand how life evolved on Earth. The experiments used interstellar model ices and estimates of Galactic Cosmic Ray levels to form Glyceric Acid with a photo ionisation laser. This may have been similar to the role of lightning in the evolution of our own atmosphere.
Source : Cheers! Webb finds ethanol and other icy ingredients for worlds and Unraveling the origins of life: Scientists discover ‘cool’ sugar acid formation in space