source : www.bangkokpost.com
European Space Agency hails ‘awesome’ achievement in capturing light from 10 billion years ago
DARMSTADT, Germany – The first images from Europe’s Euclid Space Telescope were released Tuesday, showing a nebula resembling a horse’s head, never-before-seen distant galaxies and even “indirect evidence” of elusive dark matter.
Euclid set off in July on the world’s first-ever mission, aiming to investigate the enduring cosmic mysteries of dark matter and dark energy.
It will do this in part by mapping a third of the sky – covering a mind-boggling two billion galaxies – to create what is being billed as the most accurate 3D map of the universe ever.
After joining the American James Webb Space Telescope at a stable floating site about 1.5 million kilometers (over 930,000 miles) from Earth, Euclid began sending back his first observations.
Josef Aschbacher, head of the European Space Agency, said in a statement that Euclid’s first five images were “awesome and remind us why it is essential that we go to space to learn more about the mysteries of the universe.”
They include an image of the Horsehead Nebula and part of the famous Orion constellation, as well as spiral and “irregular” galaxies.
But Euclid project scientist Rene Laureijs told AFP that the most exciting thing for the team was an image of the Perseus Cluster, a huge distant collection of more than a thousand galaxies.
In the background of the cluster lurk more than 100,000 additional galaxies, some of which, according to the ESA, are ten billion light-years away and have never been observed before.
‘Detective of the Dark Universe’
Jean-Charles Cuillandre, another scientist working on Euclid, told AFP that Euclid is different from other space telescopes because it occupies a very wide field of view, “the likes of which have never been seen before in the history of astronomy.”
By comparison, the Webb telescope “looks at the sky through the eye of a needle,” he said.
This wide field of view allows the telescope to capture such wide images extremely quickly; the five new shots took only about eight hours of the telescope’s time.
Footage from another 16 hours – a full day – will be released in January.
The ESA has named Euclid its ‘dark universe detective’, tasked with investigating why 95 percent of the universe appears to be made up of dark matter and dark energy, about which we know very little.
‘Dark matter pulls galaxies together and causes them to spin faster than visible matter alone can explain; dark energy is driving the accelerated expansion of the universe,” explains ESA Science Director Carole Mundell.
According to Laureijs, Euclid’s early images already pointed to ‘indirect evidence’ of dark matter.
For example, he said it was “surprising” that Euclid didn’t see any stars trailing the globular cluster NGC 6397, a collection of hundreds of thousands of stars.
“One of the theories is that there may be dark matter around the globular cluster, which holds all the stars together,” says Laureijs.
Walk back in time
By capturing light that has taken ten billion years to reach Earth’s environment, Euclid also hopes to better understand how dark energy has driven the expansion of the universe since the Big Bang 13.8 billion years ago.
Once Euclid has collected enough data, the scientists plan to plot a 3D map – the third dimension is time.
Laureijs said the map would allow people to “walk through a part of the sky and go back in time 10 billion years.”
But that will have to wait for future data releases on the planned six-year mission.
It wasn’t all plain sailing for Euclid.
When the scientists first began their observations, they discovered that cosmic rays were interfering with the telescope’s extremely sensitive fine conduction sensor.
The spacecraft’s software had an algorithm that was “fooled” by the cosmic rays, Laureijs said.
However, the team on the ground managed to upload a new algorithm to the spacecraft. “Now it works flawlessly,” says Laureijs.
There was also a problem with sunlight reflecting off a thruster arm, requiring the telescope to be rotated slightly, he added.
According to the ESA, a series of scientific papers analyzing what is in the five new images will soon be published.
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