Why are scientists looking for oxygen on other planets? Because it is a possible reference to the past or present existence of life. That is, a biosignature. A team from the University of California at Riverside developed a new technique for this process. They hope to identify the presence of oxygen on these planets that revolve around a star.

The exciting oxygen
A state-of-the-art telescope like Webb can be used to see what is in their atmosphere. It will focus its gaze to detect a strong signal that oxygen molecules create when they collide with one another. It is explained by Thomas Fauchez of NASA’s Goddard Space Flight Center. “This oxygen signal has been known since the early 1980s, but has never been considered for exoplanet research.”
“Oxygen is one of the most exciting molecules to discover because of its connection to life. However, we do not know whether life is the only cause of oxygen in an atmosphere. This technique enables us to find oxygen on planets, both living and dead. When oxygen molecules collide with one another, they prevent a telescope from seeing parts of the infrared light spectrum. By examining the patterns in this light, the composition of the planet’s atmosphere can be determined.

Barren planets
Some researchers believe that oxygen can also accumulate in the atmosphere of a barren planet. When an exoplanet is too close to its star, its atmosphere becomes excessively hot. It would become saturated with water vapor from the oceans which would evaporate. Over time, this process could lead to the loss of entire oceans while creating a thick oxygen atmosphere. That said, an oxygen-rich atmosphere would not necessarily be a sign of life.
Astronomers still aren’t sure how widespread this process can be on exoplanets. However, it is important to know whether and to what extent dead planets generate oxygen in the air. The researchers would continue to search for oxygen on other planets. They believe that sooner or later they will be clear as to whether it is a distinctive feature of the presence of life.