The first results from the Euclid telescope

First results from the Euclid space probe, launched last summer: it notably spotted a multitude of floating planets wandering in space, without stars.

Mathilde Fontez, editor-in-chief of the scientific magazine Epsiloon takes us into space, with the first results from the European Euclid telescope, launched last summer. It reveals galaxies, clusters of galaxies, and isolated planets, all alone in space, without stars.

franceinfo: All this data was published on May 23?

Mathilde Fontez: Yes, this is only the first burst of results from this telescope whose mission is to last 6 years. It’s a big mission from the European Space Agency: 1.4 billion euros, a collaboration of 2,500 researchers and engineers. And its main goal is not the planets, but it is about measuring the dark matter of the Universe, the 95% of the content of the cosmos, which remains unknown: we are talking about dark matter, dark energy. We see the signs, without knowing their nature.

But it is true that it is the planets that stand out, in this first harvest of scientific results, published last week: the discovery of floating planets, in the Orion cloud, a star formation zone, a stellar nursery : there, the telescope discovered 300,000 new objects, some of which are not attached to any star.

Planets without a Sun?

Yes, astrophysicists call them “floating planets” or “wandering planets.” They are big, at least the ones we see, bigger than the gas giants of our solar system. And they are 3 million years old: they are very young – our Earth is 4.5 billion years old.

They are quite hot, and therefore quite bright in the infrared, which is why the Euclid telescope was able to detect them. And they float in space, all by themselves.

Did we know that this type of planet could exist?

It has been around ten years since astrophysicists began to see them. We first believed in particular, atypical cases. Then two years ago, a French team discovered around a hundred at once, which began to make it possible to produce statistics. There would be many. There are estimated to be 2 to 3 million of them roaming our galaxy.

Which raises the question of their formation: normally, planets are born with the stars, in a cloud of dust. Were these planets ejected from their planetary systems? Were they born by a new mechanism, like stars? For the moment there is no response. We can just try to imagine them: planets spinning in the dark, on which there is no morning, no evening, never light…