CO a planet’s atmosphere could indicate habitability

Subject: Science and Tech

Section: Space technology

In the news:

An international team led by the University of Birmingham (UK) and MIT (USA), developed a ‘habitability signature.’

Details:

The findings published in Nature Astronomy introduce a practical method for habitability detection.
Past attempts to identify habitable planets lacked certainty about liquid water’s existence.
Comparing CO2 levels among planets helps identify those likely to support life due to oceans.
Earth’s CO2 dissolved in the ocean, enabling life support for about four billion years.
Analyzing CO2 levels on other planets reveals insights into Earth’s environmental tipping points.
High carbon levels on Venus might have led to its uninhabitable state despite similarities to Earth.
Carbon dioxide in a planet’s atmosphere absorbs infrared light; this measurement aids habitability assessment.
Planets in the habitable zone (not too hot or cold relative to their star) could retain liquid water on their surface.
Lower carbon dioxide levels in a planet’s atmosphere compared to its neighbours suggest potential liquid water presence.
Reduction in carbon dioxide levels might indicate gas absorption by an ocean or isolation by planetary biomass.
The team’s ‘habitability signature’ could also act as a biosignature, as living organisms capture CO2.