Astronomers might soon get their first peek into the dark universe.
On Saturday, July 1, the European Space Agency’s (ESA) Euclid spacecraft will launch on a SpaceX rocket from Florida on a mission to look into deep space and unveil the elusive dark universe — and NASA’s James Webb Space Telescope shall be a crucial partner on this cosmic quest.
After a month-long flight, Euclid will reach a vantage point about 1 million miles (1.5 million kilometers) from Earth, where it can share its cosmic accommodation with the James Webb Space Telescope (JWST), whose powerful infrared eye probes the universe because it was just 100 million years after the Big Bang.
JWST will complement a component of Euclid’s mission that may investigate the character of dark energy, the hypothetical “anti-gravity” force that scientists have proposed to elucidate why the universe is expanding at an accelerated rate. ESA will operate Euclid because it maps 36% of the observable sky over six years.
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Euclid “is greater than an area telescope; it is de facto a dark energy detector,” René Laureijs, a project scientist for the Euclid mission, said during a news conference on June 23. “It will be beautiful if the 2 telescopes are online and James Webb could follow up the brand new findings of Euclid.”
Euclid is designed to analyze dark energy, whose mysterious nature is ”the largest embarrassment we currently have in cosmology,” Guadalupe Cañas Herrera, a cosmologist at ESA, told reporters Friday.
When an immensely hot and dense universe birthed with the Big Bang about 13.7 billion years ago, space itself ballooned faster than the speed of sunshine, and the universe doubled in size at the very least 90 times. That inflation eased into a gradual growth as matter that manifested within the universe tugged at itself as a result of gravity. Nonetheless, roughly 5 billion years ago, dark energy overtook gravity because the dominant force and commenced speeding up the universe’s expansion.
To assist scientists higher understand the character of dark energy, Euclid is predicted to cover 15,000 square degrees of the sky, wherein it can survey about 1.5 billion galaxies from the early universe by capturing light that’s about 10 billion to 13 billion years old. Using these data, scientists hope to clock the universe’s expansion across eons and pinpoint exactly when dark energy — which now makes up 68% to 72% of the universe’s energy and matter — began accelerating the cosmos.
To assemble the required data, Euclid will study light from early galaxies at near-infrared wavelengths, much like what Webb does with its Near Infrared Camera (NIRCam). “Where Webb can observe extremely far back in time and zoom into the main points, Euclid can go fast and wide,” in response to ESA.
Euclid is able to viewing areas of the sky a 100 times wider than Webb’s NIRCam. For instance, Euclid will collect data from 40,000 fields of the sky, with each slice spanning two full moons and holding 10GB of information, Laureijs said. Webb would complement Euclid’s goals by providing deeper follow-up observations of smaller slices of the sky than what Euclid is able to, in addition to by investigating outliers in the information.
The widely accepted cosmological model that represents our comprehension of the universe’s history and evolution, referred to as the Lambda cold dark matter model, relies on a few assumptions. One is that general relativity stays put in cosmological scales. The model also assumes that the universe incorporates cold dark matter, which is a hypothetical variety of dark matter that moves slower than the speed of sunshine, doesn’t interact with visible matter and makes itself known only gravitationally, and dark energy, which holds on to a continuing density because the universe expands. The model lacks necessary information in regards to the nature of dark matter and dark energy, and many years of direct and indirect searches to seek out dark matter particles proceed to return up empty.
With Euclid, scientists plan to check different cosmological models that attempt to elucidate the accelerated expansion and see which one most closely fits the telescope’s data. Those results may prompt the design of a “modified gravity model or something more exotic,” Cañas Herrera said.
Ultimately, scientists hope Euclid’s findings will help explain if there’s a “revolution” needed in our understanding of the laws of nature, said Yannick Mellier, an astronomer on the Paris Institute of Astrophysics who leads the Euclid consortium. “In principle, Euclid should provide a decisive response on the character of dark energy.”