We are very excited to welcome Prof Jane Greaves from Cardiff University as the next speaker in the Centre for Exoplanets and Habitability seminar series. Prof Greaves will be giving a talk titled "Planets, Exoplanets, & Life" on Friday 16th June 2023.

Abstract:
So what was all that furore about phosphine? I will report on new observations of phosphine in Venus' clouds, and place these in the context of possible sources, such as active volcanoes or even extant life. New techniques are being developed for agnostic biosignatures, and new models are emerging for biosignature gases in different planetary environments. I will discuss the crossover of these advances for exoplanetary science and some of the lessons learned from solar system life searches. Finally, I will introduce some ongoing observing campaigns that can help to assess habitability of rocky exoplanets.

On 14 September 2020, a team of astronomers led by Dr Jane Greaves of Cardiff University announced the detection of phosphine, a potential biomarker, in the atmosphere of Venus. On Earth, phosphine can result from natural processes such as lightning and volcanic activity, but only in small amounts; by comparison, the amount of phosphine detected in Venus' atmosphere is relatively large. The only known processes that produce phosphine on Earth in similar quantities are biological in origin.

It must be stressed that this does not mean that there is life on Venus. What has been announced is a signal that is a possible sign of life, with a strength for which there are no plausible known abiotic explanations. There may, of course, be currently unknown methods of producing it in the amounts required. But this is still an exciting signal that warrants more investigation.