Euclid: ESA’s mission to deep space will start in July

Go in search of the “dark side” of the Universe. That, more or less, is the goal of Euclidthe Exa mission (European Space Agency) that has just successfully passed some of the tests planned before the launch, scheduled for July 2023. Euclid will begin its flight into deep space from Cape Canaveral, Florida (United States), and the launch vehicle will be a SpaceX Falcon 9, Elon Musk’s aerospace agency. The goal of the mission is to explore the nature of dark energy and dark mattermysterious components of our Universe that science has been trying to better understand for some time.

Dark matter and dark energy

But what exactly are we talking about when we talk about energy and dark matter? And above all, why do we care so much? “At the moment Euclid is the most complex mission in terms of scientific objectives”, he said Barbara Negri, head of ASI (Italian Space Agency) for human flight and scientific experimentation for the Euclid mission. “The current cosmological model sees the Universe composed of 5% visible matter, 25% dark matter that does not emit light and 70% dark energy. Starting from this information, scientists want to try to understand why the Universe is moving faster than predicted by the model and whether matter and dark energy play a role in this acceleration”. What exactly dark matter and dark energy are we still don’t know, which is why scientists use this adjective to describe them. We suspect their existence because, so to speak, some accounts don’t add up. We speak in particular of the so-called “Standard Model”, which describes most of the natural phenomena very effectively, starting from the interactions of the particles we know. Some celestial body behaviors, however, are not predicted correctly based on this model alone. And the existence of a type of matter and energy of which we do not know exactly the characteristics, and therefore the behavior, is the only way we currently have to explain these divergences. But while we know a little more about dark matter, even if we have never been able to detect it directly, dark energy remains a complete mystery. According to existing models, its presence in our Universe could explain some experimental evidence that we cannot fully understand, for example why the Universe is expanding rapidly.

Details on the mission and the Italian contribution

Euclid’s “ticket” has as its destination the Lagrange point L2 between the Sun and the Earthwhich is about 1.5 million kilometers from us. The powerful detection instruments housed within the satellite will aim to create a huge map of our Universe, collecting data on over a billion different galaxies.

Italy is involved in the mission on various frontsincluding the contribution to the creation of the two on-board instruments: “Euclid – continues Negri – it is equipped with a 1.2-metre telescope – designed to work at the visible and near-infrared wavelengths – which will collect light from cosmic objects up to 10 billion years away and send it to the two on-board instruments, which work in parallel : Vis (Visible Instrument)for which the British are responsible e Nisp (Near Infrared Spectrometer and Photometer) for which the French are responsible. And we have contributed to both. Euclid will measure the shape of tens of millions of galaxies and their redshift. The redshift of the wavelength or redshift is an effect of the accelerated expansion of the Universe: the farther the galaxy moves, the greater the redshift”.

In these days, we said, Euclid has been subjected to electromagnetic compatibility tests, designed to simulate the electromagnetic environment of deep space and to ascertain that in such conditions there is no interference between the various electronic devices within the satellite. These are routine tests for spacecraft, which Euclid successfully passed. We just have to wait for July to see it take off.