A mind-boggling number of glittering galaxies, purple and orange star cribs and a spiral galaxy similar to our own Milky Way: new images were revealed by Europe’s Euclid Space Telescope on Thursday.
It is the second set of images released by the European Space Agency since Euclid launched last year on the first-ever mission to explore the mysteries of dark matter and dark energy.
Science results were also published for the first time on the six-year mission, which aims to use its wide field of view to map two billion galaxies across a third of the sky.
Project Euclid scientist René Laureis told AFP he was “personally most excited” by the image of a massive galaxy cluster called Abell 2390.
The image of the cluster, which is 2.7 billion light-years from Earth, includes more than 50,000 galaxies.
Just one galaxy – like our own – can be home to hundreds of billions or even trillions of stars.
Abell 2390 alone contains the mass of about 10 trillion suns, Jason Rhodes of NASA’s Jet Propulsion Laboratory said at an online news conference.
The image also pointed to traces of dark matter, whose invisible presence can only be detected by seeing how its gravity bends light.
“There’s so much dark matter in this cluster that it strongly bends the light from some of these background galaxies,” making them appear curved, Rhodes said.
Dark matter and dark energy are thought to make up 95 percent of the universe, but we know next to nothing about them.
Another way the image of Abell 2390 hinted at dark matter was by revealing the faint light of “orphan stars” moving between galaxy clusters.
These stars are ejected from the galaxies, “creating a kind of cloud that surrounds the whole cluster,” French scientist Jean-Charles Quilandre told AFP.
Astronomers believe that this strange phenomenon indicates the presence of dark matter between galaxies.
– A star is born –
Euclid also captured the deepest image yet of Messier 78, a nursery where stars are born 1,300 light-years from Earth in the constellation Orion.
Stars are still forming in the bluish center of the image. After gestating for millions of years, they emerge from the purple and orange clouds at the bottom of the image.
Laureis emphasized that “only Euclid could show this in one shot.”
That’s because Euclid has a very wide field of view, unlike far-sighted fellow James Webb Space Telescope, its stable-orbiting neighbor 1.5 million kilometers (930,000 miles) from Earth.
Another image, of the huge galaxy cluster Abell 2764, shows a black expanse in which a single yellow star stands out.
Quilandre admitted that this was the result of an error in pointing the telescope. But he said the image demonstrated Euclid’s “absolutely unique ability to concentrate light” as it still managed to pick up very faint objects next to the bright star.
Euclid’s image of the young dorado bunch contained a surprise. Although the cluster was already well-studied, Euclid discovered a never-before-seen dwarf galaxy, the scientists said.
“I’ve never seen anything like it,” Quilander said.
In the fifth new image, the spiral galaxy NGC 6744, which bears a striking resemblance to the Milky Way, spreads out against a background of glittering stars.
– In the wake of dark matter –
It’s still early days for the mission, and the five new images were captured in just one day.
In the coming years, scientists plan to sift through Euclid’s data in hopes of spotting any celestial bodies, such as “rogue” planets that float freely in space unattached to a star.
But researchers have already analyzed the first batch of Euclid images, which were published in November.
In one of 10 preprint studies published Thursday, scientists examined orphan stars in the Perseus cluster.
These lost stars “are now trapped by the gravity of dark matter,” Laureis said.
This remains only an “indirect detection of dark matter,” he stressed, adding that it is too early “to say anything about dark energy.”
The mission was not entirely smooth sailing.
In March, a delicate operation successfully melted a thin layer of ice that was slowly obscuring the telescope’s vision by warming one of the telescope’s mirrors.
There are signs that the ice is accumulating again, Laureis said, adding that the team has time to study what to do next.
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