At 11:12 a.m. Saturday, the Euclid spacecraft blasted off into space on its mission to chart the history of the universe 10 billion years ago.
The space telescope, built by the European Space Agency, will use its instruments to record more than a third of the sky outside the galaxy over the next six years, creating the most accurate 3D map of the universe yet.
The researchers plan to use Euclid’s map to explore how dark matter and dark energy — the mysterious stuff that makes up 95 percent of our universe — has affected what we see when we look across space and time.
“Euclid comes at a really exciting time in the history of cosmology,” said Jason Rhodes, a physicist at NASA’s Jet Propulsion Laboratory who leads the Euclid Science Team in the US. “We are entering a time when Euclid will be great at answering questions that are just starting out. And I’m sure Euclid will be great at answering questions we haven’t even thought about.”
The spacecraft lifted off from Cape Canaveral, Florida, on a SpaceX Falcon 9 rocket. The weather was almost perfect for the trip. Euclid, still attached to the rocket’s second stage, separated from its booster three minutes after launch, to a flurry of applause in the control room. It entered a stable Earth orbit about nine minutes into flight, before a series of maneuvers to put the telescope on a trajectory to its final destination in space.
The European astrophysics mission had no choice but to fly America. The European Space Agency planned to launch the spacecraft on either of them Russian Soyuz missile Or the new Ariane 6 missile in Europe. But due to the rupture of European-Russian space relations after the invasion of Ukraine, and the delay of Ariane 6, the European Space Agency Moved some launches to SpaceXincluding Euclid.
The spacecraft won’t be alone looking into the cold storage of our universe. But unlike the Hubble and James Webb space telescopes, which focus deeply on one part of the sky at a time, scientists will use Euclid to cover large swaths of sky outside the galaxy at once. In three of the regions he recorded, Euclid will go back even further, to depict the structure of the universe about a billion years after the Big Bang.
One of the space telescope’s targets is dark matter, the invisible glue of the universe that doesn’t emit, absorb, or reflect light. Dark matter has so far evaded direct detection, despite physicists’ best efforts, but they know it exists because of its gravitational influence on the way galaxies move.
On the other hand, dark energy is an even more mysterious force that is pushing galaxies apart – so much so that our universe is expanding at an accelerating rate.
Euclid’s maps of the universe will reveal how dark matter is distributed across space-time based on how light from galaxies behind it is distorted, an effect known as weak gravitational lensing. (This is different from strong gravitational lensing, the more dramatic distortion by galaxy clusters that create arcs, rings, or even multiple images of a single source.)
These measurements contribute to more direct efforts to find out what dark matter actually is.
“We’re looking for the same thing from different angles,” said Clara Nellist, a particle physicist at CERN in Europe who is not part of the Euclid mission. Researchers are looking at ground-based experiments for signs of dark matter particles colliding with their detectors. “Any information we gather about how it’s distributed in our universe helps us look for it in our collisions in a more focused way,” said Dr. Nellist.
With Euclid, scientists hope to be able to test whether Albert Einstein’s general theory of relativity works differently on cosmic scales. This could be related to the nature of dark energy: whether it is a static force in the universe, or a dynamic force whose properties vary over time.
“If we discover that this is not a constant, but something that changes over time, it will be revolutionary,” said Xavier Dupac, an ESA cosmologist on the Euclid mission, “because it would upend what is known about fundamental physics.” Such a discovery could shed light on the ultimate fate of what appears to be our ever-expanding universe.
Euclid hosts a visualizer consisting of a 600-megapixel camera that can image an area as wide as the sky of two full moons simultaneously. With this tool, scientists will be able to see how the shapes of galaxies are distorted by the dark matter in front of them.
It also has a near-infrared spectrometer and photometer, which will be used to record galaxies at invisible wavelengths as well as measure their redshift, which is the effect of wavelength stretching in light from the distant universe that results from the expansion of the universe. When used with a range of ground tools – incl Subaru And Canada, France and Hawaii telescopes at the Mauna Kea Observatory, and eventually the Vera C. Ruben Observatory in Chile—scientists will be able to convert the redshift into measurements of distance from Earth.
While Euclid was launched successfully, it is now making a journey of nearly a million miles from Earth into orbit around what is known as a second Lagrangian point, or L2 — a place in the solar system where the Earth’s and sun’s gravity cancel out. Facing directly away from the sun, this site also strategically places Euclid in a spot to take wide surveys of the sky without the Earth or Moon obscuring its view. The James Webb Space Telescope orbits L2 for the same reason.
It will take about a month for the spacecraft to reach L2, and another three months to test the performance of Euclid’s instruments before it begins sending data back to Earth for scientists to analyze. This data will be released to the public in 2025, 2027 and 2030.
in news briefing beforehand Last week, Yannick Millier, an astronomer at the Astrophysical Institute in Paris, said that in addition to his main science goals, Euclid would create a unique survey of the sky of 12 billion galaxies with image quality rivaling that of Hubble.
It will be “a gold mine for all areas of astronomy for many decades,” Dr. Millier said.