Produced by: Tarun Mishra
Astronomers are expanding the search for extraterrestrial life by considering the possibility of purple bacteria, which may offer a unique perspective on life beyond Earth.
The study aims to create a database of potential signs of life, acknowledging that alien life forms may not resemble those found on Earth and ensuring that telescopes are equipped to detect diverse forms of life.
Purple bacteria are adaptable organisms capable of thriving in various environments, suggesting they could potentially emerge on exoplanets orbiting dim red stars similar to our sun.
On Earth, photosynthesis initially relied on a molecule called retinal, found in purple bacteria, before transitioning to chlorophyll-based photosynthesis. This historical shift offers insights into potential alternative forms of photosynthesis on other worlds.
Purple bacteria utilize retinal pigment for photosynthesis, offering a distinct biosignature that could be detectable by upcoming telescopes equipped to analyse exoplanet atmospheres.
Scientists collected purple bacteria from diverse environments and analysed their chemical composition to develop a catalogue of potential biosignatures. Computer simulations were then employed to model scenarios where purple bacteria dominate on Earth-like exoplanets.
Next-generation telescopes, such as the European Extremely Large Telescope and NASA's Habitable Worlds Observatory, will utilize this data to enhance their search for alien life by considering a broader range of potential biosignatures.
Researchers emphasize the importance of expanding our understanding of potential life forms beyond traditional expectations, highlighting the diverse possibilities awaiting discovery in the universe.