This is a refreshing and sober thought. All the planets, galaxies, starlight, and other objects in the universe that we can see and measure make up only 5 percent of existence. The remaining 95 percent is engulfed in two mysteries: dark matter and dark energy, which are known to scientists by their apparent gravitational effects on the surrounding universe but cannot be detected directly.
But a new European Space Agency mission on July 1 could help scientists get a little closer to unraveling the twin mysteries of dark matter and dark energy. The Euclid Space Telescope will be aboard SpaceX’s Falcon 9 rocket and will fly from Space Force Station Cape Canaveral by 11:11 a.m. EDT. NASA Live stream the launch from 10:30 am
After launch, Euclid will take about 30 days to reach operational orbit around Lagrange Point 2 (L2). Lagrange Point 2 (L2) is an area one million miles away toward the outer solar system where Euclid can maintain a constant position relative to Earth. The James Webb Space Telescope also orbits her L2.
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Once on site and operational, Euclid will begin a mission expected to take six years, surveying one-third of the sky and exploring billions of galaxies up to 10 billion light-years away. Carefully measure the shape and get a glimpse of what it looks like. About how dark matter and dark energy shape our universe. To do so, the space telescope, which weighs about 4,600 pounds, uses a 4-foot-wide primary mirror to collect and focus light in the visible and near-infrared wavelengths. two instruments: visible instrument camera and near-infrared spectrometer and photometer. This helps determine the distance to distant galaxies.
“The magnificence of how many galaxies Euclid can measure with astonishing accuracy is truly an amazing feat of ergonomics,” he says. Lindley Winslow, a physics professor at MIT who plans an experiment to detect dark matter, but is not directly involved in this mission. “The fact that we can do a precise cosmology is great.”
Cosmologists who study the formation, evolution, and structure of the universe have a model called Lambda CDM That might explain why everything is the way it is. Lambda is the cosmological constant, the force that seems to be accelerating the expansion of the universe, and scientists believe it is related to, or manifests in, the mysterious dark energy. CDM stands for “cold dark matter” and interacts gravitationally with ordinary matter.
“These are the two elements that shaped the universe as we know it,” says Winslow. Dark energy causes the universe to expand, but “in the early universe, it pulled the visible matter we see now into potential wells, allowing it to contract and form galaxies and stars.” It was this cold dark matter that made it possible.”
According to Winslow, the lambda CDM can help interpret much of the large universe, but how it fits in with the theory that explains how the small universe works: the standard model of particle physics. I can’t tell you what to do. Euclid is one of several attempts to learn more about how the universe is extended and the Lambda-CDM revised.
“What we’re really interested in is whether we can get more data,” says Winslow. “And can we find something that Lambda-CDM can’t explain?”
To look for that evidence, Euclid uses a technique known as weak gravitational lensing. This is similar to the powerful gravitational lensing technique employed by JWST. This technique uses the mass of foreground objects such as galaxy clusters to magnify more distant background objects. Weak gravitational lensing has made scientists even more interested in how the masses of foreground celestial bodies, including dark matter, create subtle distortions in the shape of background galaxies.
“We’re using the background galaxy to know the distribution of matter in the foreground,” he says. Rachel Mandelbaum, an astrophysicist at Carnegie Mellon University and a member of the US portion of the Euclid Consortium, a group of thousands of scientists and engineers. “We’re trying to measure the shape of the galaxy and the influence of whatever material is in between us.”
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The method is also useful for measuring the effects of dark energy, Mandelbaum added. Dark matter helps all other matter to clump together, and dark energy counteracts the gravitational effects of dark matter by measuring how much matter clumps together over a range of distances from Earth. We measure how structures grow and use that to infer the effect of dark energy on matter distribution.”
Euclid is not the first large-scale sky survey to use weak gravitational lensing to look for dark matter and dark energy signatures, but it will be the first of its kind in orbit. In previous research, dark energy research, All of this was done by ground-based telescopes, Mandelbaum said. Standing in space has another advantage.
“Terrestrial telescopes see blurrier images than telescopes in space due to the influence of the Earth’s atmosphere on the light of distant stars and galaxies,” Mandelbaum said. Euclid’s perspective from L2 is useful when “trying to measure very subtle distortions in the shape of galaxies.”
But dark matter and dark energy are elusive mysteries, and scientists have access to all the data they can collect from as many angles as possible. The Vera Rubin Observatory is currently under construction in Chile and is scheduled to open in 2025 with ground-based observations. Space-Time Legacy Investigation Examine the entire southern sky for similar phenomena. Mandelbaum said such efforts help ensure the reproducibility of Euclid’s findings, and vice versa.
“Euclid is a very exciting experiment in a wide range of investigations trying to reach the same science, but with very different datasets with different assumptions,” she says. “They’re going to do something a little different that gives us a different approach to answering these really basic questions about the universe.”
