CAPE CANAVERAL – Fly Euclid, the telescope of the European Space Agency (ESA) is took off at 17:12 Italian time from Cape Canaveral, leading a SpaceX Falcon 9 rocket towards his place out there from which, in the coming years, he will try to shed light on that piece of reality that we still cannot explain. AND one of the most important Esa missions of recent years (cost 1.4 billion), especially as scientific ambitions, which seeks a breakthrough to better understand dark matter and energy, everything that is not ordinary matter and energy: 95% of everything that fills the Cosmos. The first stage of the carrier has carried out its task, returning and landing (but by now it is a custom that is no longer news) on the marine platform off the coast of Florida. Now we just wait for the release of Euclid, expected 40 minutes after the liftoffat 17:53.
Euclid Space: the European look at the dark matter of the Universe by Emilio Cozzi 25 February 2023
The Falcon 9 gave the push Euclid needed to reach the Lagrangian point L2, a fairly stable gravitational equilibrium zone, where the James Webb and Gaia telescopes are also located. From there it will be able to photograph and scan over a third of the sky in the next six yearsto search for clues in the dark, the blackest one: the main purpose will in fact be to measure the effects of the presence of matter invisible to all instruments, and which nevertheless innervates the void between the galaxies and influences their movements, and of that energy which it makes the Universe not only expand, but actually accelerate.
The dark majority of the Cosmos
Even if the stars seem endless, the galaxies countless, the bill for astrophysicists is embarrassing. By adding matter and dark energy, according to the well-known equivalence of mass and energy that Einstein taught us with special relativity, we obtain that 95% of what we have around us from here to the end of space and time is shrouded in mystery. They are not atoms, ordinary matter, they are not radiation. We don’t know what it is, but we see its effects.
Aerospace Logistics Technology Engineering Company Marte, Turin suburb by Bruno Ruffilli 05 May 2023
It will take Euclid a month to reach L2, as the James Webb will position itself with its back to the Earth and the Sun, protected by a shield, its infrared instrument will in fact have to work at temperatures below -130 degrees below zero, it will therefore use the weeks of travel to cool down. Three months later, once the tests on the functioning of the instruments are over, he will start doing science and using his 1.2 meter diameter mirror to collect the clearest light of galaxies scattered across the sky from here at a distance of ten billion light years.
But just why seek not only the invisible, but the imponderable, the evidence it will bring will be indirect, and its measurements will need to be ultra-precise. In each tile of the sky he will photograph thousands of galaxies, there will be at least a billion and a half in the end, to create a 3D map with the position and distance of millions of stellar clusters and measure the speed at which they are moving away from us. All this amount of data (50,000 images of over 600 megapixels each, something like 100 terabytes a year for six years” are the estimates) will be sorted and managed by the ground segment, the other major element of this mission: the science data centres, which will be coordinated by Italy, through the INAF (Trieste Observatory), which has also created the on-board software for the two instruments, with the support of theItalian Space Agency (ASI).
Space Ready to take off Euclid, which will investigate Matteo Marini’s dark Cosmos 14 June 2023
Italy which has a leading role in this adventure, second taxpayer behind France, as an investment in the consortium that brings together the work of 300 institutions in 17 different countries, with 13 space agencies, plus NASA, which supplied the sensor for the Nisp instrument. The international collaboration has more than 3,500 people: “Exactly ten years ago we signed the contract for Euclid – remember Walter Cugno, vice-president, Exploration & Science of Thales Alenia Space, the company prime contractor for the construction of the satellite – not because we have been slow, but because there have been many difficulties, with 80 companies and 140 industrial contracts, hundreds of suppliers. And because it is always difficult to satisfy all the requests of the scientific community”. Thales Alenia Space, in Italy, was responsible for the construction and integration of the spacecraft, the structure on which the telescope and instruments are mounted. The construction of the Italian data center (there are eight in Europe, one in the USA) was entrusted by ASI to Altec in Turin.
The shape of galaxies
The Visible instrument is a chamber that collects light in the wavelengths that the human eye perceives with a sharpness impossible for ground-based telescopes, thanks also to the orientation and stability mechanisms. In fact, to aim, Euclid has a stellar sensor and a pointing system with microthrusters for infinitesimal corrections, Italian technology, supplied by Leonardo, together with solar panels. The field of view will be a “wide angle”, to cover a portion of the sky almost the size of three full moons with each shot.
The launch Scientists arrived from Italy to see Euclid take off: “A piece of us flies into space” by Matteo Marini 01 July 2023
Such precision serves to draw the shape of galaxies it’s at measure the very small distortions of light (“weak gravitational lensing”), caused by the presence of dark matter, of its cobweb between us and those objects. It is one of the spacetime distortion effects predicted by Einstein’s Relativity: gravity distorts spacetime, and bends light. Dark matter does it too, but unlike stars and galaxies, which are made of atoms, it acts without showing itself: “Euclid has the ability to cover the entire sky in a short time, which is not occupied by the Milky Way and the dust solar system – underlines Giuseppe Racca, ESA’s Euclid project manager – to indirectly measure these enormous effects at a universal level, but it will have to do so with unprecedented, extreme accuracy”.
The escape of the galaxies
Nisp stands for Near infrared spectrometer and photometer, and captures light in the near infrared. From that, he will extract the spectrum of galaxies which will be like a velox for us: it will tell us both their distance and the speed with which they move away measuring the effect of their escape on light shifts towards the red. This is how he will shape the 3D map of the universe but in doing so he will also trace its history and evolution. It will be a scan ten billion light years deep, this time to measure the effects of the other unknown of this puzzle: the Universe has accelerated its expansion in the last five billion years, these are the effects of dark energy.
However, everything originates after the Big Bang, when the conditions for the formation of stars and galaxies were created from the ripples in the primordial ‘soup’ of particles. It has a difficult name: baryonic acoustic oscillation, it can be imagined as sound waves that initially disturbed the state of matter, creating differences, this generated the distribution of galaxies in space, like a footprint that has been expanding, shaping the geography of ‘Universe. Since observing far in space means going back in time, Nisp’s measurements will give us the knowledge of how galaxies have been distributed and moved over the last ten billion years, since when this expansion seems to have accelerated under the thrust of the dark energy. But as he commented Henk Hoekstra, cosmologist of the Euclid consortium, the truth is that dark matter and energy could have other explanations than those expected: “It will be like looking for a black cat in a dark room. But we could also discover that it is not there. It is a great time to be a cosmologist, Euclid will change the research of the future”.