Finding aliens


The Drake equation to estimate the number of alien civilisations in the galaxy was created in the 1960s to stimulate scientific dialogue on the search for intelligent extraterrestrial life. Inspired by this, Professor Lee Cronin (in collaboration with Caleb Scharf, Director of Astrobiology, Colombia University) has developed a new equation that could help predict the likelihood of life arising on other planets in the universe.

The equation incorporates factors such as:

  • the potential available chemical building blocks in a planet
  • the number of building blocks required for a living system

Examining plausible values for these parameters guides astronomers to investigate those planets most likely to facilitate origin of life events.

This approach has observed that the exchange of complex materials between planets within a solar system could significantly accelerate the rate of origin-of-life events within that system. This is known to have happened between Earth and Mars. This insight could allow astronomers in the search for alien life to focus on systems that contain multiple planets with potential.

Creating life

To understand the origin of life on Earth and identify promising targets in the search for life on other planets, we have to understand how matter can move from a non-living to a living state.

Previous research has tended to focus on the biochemistry of life as we know it today. However, Glasgow researchers propose a radical rethink to explore not only plausible chemical scenarios but also new physical processes and driving forces. This could lead to a physical understanding of the origin of life, as well as new tools for designing artificial biology.

In the Science article “Beyond prebiotic chemistry”, Professor Lee Cronin and Professor Sara Walker (Arizona State University), discuss a new approach to understanding the transition from non-living to living systems. By challenging historical assumptions and taking a multidisciplinary approach, they suggest that researchers could develop a new type of complexity-first-based model; a model that expands the types of chemistries to be explored and leads to a comprehensive understanding of what it means for a system to be alive.