James Webb Discovers a Crucial Element for Life on Four Exoplanets

NASA announced that CO2 had been spotted in a planetary system located 130 light years from Earth. What revive hope concerning an extraterrestrial life form?

A first for James Webb

It was in a study published on March 17, 2025 in The Astronomical Journal that researchers from Johns Hopkins University In Baltimore (Maryland, USA) revealed this discovery. Indeed, by pointing the objective of the James Webb space telescope to the HR 8799 exoplanetary system, scientists were able to directly detect CO2 in the atmospheres of the four exoplanets of the system.

A great first for the telescope since this detection was done directly. It is by using the coronographers of the astronomical telescope, which are used to obscure all or part of the light emitted by the mother star of the system, that the researchers were able to identify the signature of CO2 thanks to the light emitted by the exoplanets.

An incredible discovery because CO2 or carbon dioxide is an essential gas for the establishment of life. Indeed, on earth, it is partly thanks to him that we can live outside. Without CO2, the infrared rays from the sun would come to the surface of the earth, which would have the consequence, a drastic increase in temperature.

CO2 out of four exoplanets, but impossible that life was established there

Although CO2 has been detected in the HR 8799 exoplanetary system, it is not possible that life, as we know it, has been able to develop. For what ? Well, because the four exoplanets constituting the system are gaunt giants like Jupiter or Saturn in our neighborhood.

But if the disappointment is great, this discovery made at 130 light years from the earth has something to give hope to those who hope to find an extraterrestrial life form outside the solar system.

The first reason lies in the fact that the four exoplanets may have moons which would be very telluric and therefore which could attract part of the captured gases, such as CO2, by their exoplanets to build up an atmosphere. Life could then develop not on a planet, but on a natural satellite of the latter.

And the second reason is a question of age. Our solar system is 4.6 billion years old and life appeared on Earth more than 3.5 billion years ago. On the side of HR 8799, the system would barely be 30 million years old. To get an idea, it would be “born” 36 million years after the extinction of dinosaurs. It is therefore a “baby system” which thanks to the CO2 observed in the atmosphere of its planets could lead to the development of a form of life potentially similar to ours, on their moons.

So let it have time, if the magic worked with us, why could it not take place elsewhere?

Source: NASA