Student Research Spotlight: Rebecca Auchettl

Unveiling the complex chemistry of Titan’s atmosphere

If you’re searching for other places in our solar system that might be hospitable for some form of life, there may be no better place to look than Titan, Saturn’s largest moon. The Cassini-Huygens space probe, which visited Titan from 2005-2006, demonstrated that Titan has a dense atmosphere of hydrocarbons with liquid oceans and seasonal weather.

Titan’s atmosphere is primarily composed of nitrogen (N2) and methane (CH4). Bombardment of Titan’s atmosphere by high-energy particles causes these gases to split and recombine, producing an array of hydrocarbons and nitrile molecules that, in turn, can build up to more complex molecules and eventually form amino acids and nucleobases – the building blocks of life.

To understand more about the composition of Titan’s atmosphere and these processes that form complex molecules, AINSE PGRA scholar Rebecca Auchettl, alongside collaborators from ANSTO and La Trobe University, used far-infrared spectroscopy at ANSTO’s Australian Synchrotron to investigate planetary and interstellar ice signatures, and to attempt to resolve an unknown molecular signal recorded by the Cassini-Huygens probe that appears in Titan’s summer season and disappears in its winter.

The new reflection-absorption-infrared-spectroscopy (RAIRS) setup at the Australian Synchrotron, constructed by Rebecca’s team to help investigate planetary ices and condensates.

Far-IR instrumentation has been proposed as an important tool for future exploration of distant, icy environments, such as those found in the outer solar system. As the use of far-IR instrumentation grows, the signatures by Rebecca and her collaborators will play a vital role in aiding the future detection of interstellar ices, and the search for molecules in Titan’s atmosphere and elsewhere that are crucial to the chemical origin of life.

To read more about Rebecca’s research, please see page 31 of the 2019 AINSE Annual Report.

Next Student Research Spotlight: Zhibin Wu (Boosting battery performance with a new composite electrode)
Previous Student Research Spotlight: Calina Betlazar (How do low doses of radiation affect the brain?)