Searching for the origins of life in space with 8.9 million euros
With 8.9 million euros from the Danish National Research Foundation, Aarhus University and Leiden Observatory will establish the Center for Interstellar Catalysis. The centre is led by Aarhus professor Liv Hornekær and aims to find out how and when the building blocks of life formed in the Universe. Leiden professors Harold Linnartz and Ewine van Dishoeck are key participants.
Is there life out there? Many of us probably think about this when we look up to the heavens on a starry night. But there are some who think: I wonder whether the Universe created sugar and fat before or after the stars and the planets were formed? No, it is not about combining philosophy with the Great Bake Off. It is a deep and fundamental scientific question about the origin of life. Carbohydrates, fats and proteins are the building blocks of life, at least as we know them, and science has found them in both meteorites and comets. But how did these complex molecules form?
Complex chemistry in a cold vacuum
Can sugar, amino acids, fats, and DNA bases be formed under the extreme conditions in interstellar space: in a vacuum with temperatures close to absolute zero? Or do they need pressure and heat from stars and planets? This is the first question that the new Center for Interstellar Catalysis, or InterCat, will try to answer.
The researchers at InterCat will explore the molecular conditions that triggered the origins of life in the entire Universe. They will be testing the hypothesis that nano-sized interstellar dust particles, eventually covered by thin layers of ice, act as catalysts in chemical processes in space that result in the formation of complex organic molecules.
Universal or local life?
‘If we find out that the DNA bases and amino acids on which life on Earth is based can easily arise under interstellar conditions, this will indicate that chemical developments have been the same in other places in the Universe. This would mean that the molecular building blocks of life as we know them can be widespread throughout the Universe,’ says Liv Hornekær, who works at the Aarhus Department of Physics and Astronomy.
‘And if we find out that other types of DNA bases, amino acids and biologically relevant molecules can be formed even easier, this will indicate that local conditions, such as on Earth, can put strong chemical limitations on the way in which life evolved,’ she adds. When the researchers have found out what conditions are required to form the building blocks of life, they will start investigating the second question: how the formation of stars and planets influences the development of complex molecules.
A collaboration with a history
The processes at play are simulated in sophisticated laboratories, both in Aarhus and in Leiden, supported by accurate simulations and subsequently investigated in space using world’s largest telescopes. The Laboratory for Astrophysics at Leiden Observatory plays a central role in InterCat; it is one of the leading places to study the formation of complex molecules in interstellar ices. The Danish and Dutch team have known each other already since 2006 and over the past ten years they were involved in two large European consortia that studied the chemistry of the heavens. Harold Linnartz: ‘InterCat is a unique chance to investigate the universality of chemistry in space and what this means for the conditions required for life to start at other places as well.’
Observations and lab studies
‘My team will study the formation of complex organic molecules on icy dust particles in the lab,’ says Linnartz. ‘We will do this under conditions similar to those in dark interstellar clouds and so-called protoplanetary discs – the places in space where new stars are born and new planets form from the material that was chemically enriched in the interstellar medium, that is, the material containing complex organic molecules. In parallel, Van Dishoeck and her team will compare these lab results with astronomical observations.’
This article is based on the news item of Aarhus University/Peter F. Gammelby