Today we know of at least 6,000 extrasolar planets, they are those that revolve around a star other than our Sun. For the moment we are only able to find those that are quite large and close to us, due to the limitations that our means of investigation have for the moment, even if they are very perfect and efficient.
There are all kinds of them, large and gaseous like our great Jupiter or, in much smaller numbers, small and rocky like our Earth or Venus, However, until now there had never been evidence of a rocky planet, like ours, with an atmosphere around it.
Thanks to NASA‘s powerful James Webb telescope, we have the evidence today. The alien world that has been talked about these days, ever since an important research by an international group of astrophysicists was published in the authoritative journal Astrophysical Journal: it is called TOI-561 b, technical name that identifies the parent star and also one of the three planets that revolve around it, and it would have an atmosphere, albeit a very particular one.
Be careful that it is not easy to find an exoplanet and even less to understand if it has an atmosphere. Let’s take an example of ourselves: The Earth has a diameter of about 13,000 kilometers, a little less, and an atmosphere that is let’s say 100 kilometers thick, even if the one in which we can breathe is less than a tenth.
If we mentally reduce the Earth to the size of a round watermelon, the atmosphere will be much thinner than a light sheet of plastic, the kind we use to preserve the freshness of food in the refrigerator. This example shows us how difficult it is, billions of billions of kilometers away, to understand whether the atmosphere is there or not, and at the same time also how delicate the Earth’s atmosphere is, which allows us to live by breathing.
