Extract from ABC News
Emerging from the dust of an intergalactic cloud, a mane of gas stretches out from a swirling landscape, pockmarked by dazzling lights. The horse rears its head from a turbulent river, looking off in the distance at the sea of stars.
This is the Horsehead Nebula, a stunning region of space in the constellation Orion. It lies approximately 1,375 light-years from Earth.
It was captured in stunning detail by the European Space Agency's Euclid space telescope, revealing a region of space rich in star-forming activity like never seen before.
And it took just one hour for Euclid to snap the shot.
Euclid hasn't quite received the same amount of attention as NASA's James Webb Space Telescope (JWST), the golden-mirrored child of next-generation space telescopes, or its predecessor, Hubble, but it's just as impressive as both of them.
"In a couple of days Euclid will cover more area of sky than Hubble did over its entire lifetime," said Simon Driver, an astronomer at the University of Western Australia and International Centre for Radio Astronomy Research.
And in its first release of colour images overnight, the 1 billion Euro ($1.66 billion) telescope produced images just as impressive as anything its sister space telescopes have ever beamed back to Earth.
What is Euclid?
Euclid is a space telescope named after the Greek mathematician Euclid, considered the "father of geometry."
It launched on July 1 aboard a SpaceX Falcon 9 rocket.
Since then Euclid has travelled around 1 million kilometres to reach its vantage point, where it will be in a stable orbit between the Earth and the Sun across the length of its six-year mission.
During its mission, Euclid will constantly take wide images of the cosmos at high resolution to answer one of the enduring mysteries of the universe: Where is all the matter?
The stuff we can see and detect with our telescopes only makes up 5 per cent of the universe.
The other 95 per cent is composed of dark matter and dark energy so-named because they are invisible to us. We don't know what they are, but based on how they interact with gravity, we know they exist.
Euclid will look at the sky in visible light and near-infrared, determining how far away galaxies are (and thus, how old they are) as well as their shape.
It has two main instruments for capturing those wavelengths of light — VIS, which sees the universe in visible light and NISP, which studies it in near-infrared (which is invisible to the human eye).
"With Euclid we can resolve the fine details of the structure of galaxies, shapes, morphologies over the full timeline of the Universe," Professor Driver said.
"More importantly we can see how their shapes are distorted by dark matter bending the light."
That's why the European Space Agency (ESA) has dubbed it a "dark matter detective."
Big ball of stars
This is globular cluster NGC 6397, which lies approximately 7,800 light-years from Earth. It was captured after five hours of observation using the VIS and NISP instruments.
In the centre of the image are hundreds and thousands of stars, packed tightly by gravity. As you move towards the centre of a globular cluster, the amount of stars skyrockets.
You'll notice, if you focus on the stars, they have a similar six-pointed spike or "spider" that has been seen in JWST images. This is due to the way the light bounces into the telescope's sensors.
The stars within a globular cluster are some of the oldest found in a galaxy, which means they likely formed during the early days of the galaxy's creation.
However, scientists aren't exactly sure how globular clusters are formed and if they're related to the evolution and development of galaxies.
The ESA says no other telescope can currently observe an entire globular cluster in one single observation and at the same time distinguish so many stars.
"There is unbelievable beauty in the Euclid images if you zoom right in," said Edward Taylor, an astronomer at Swinburne University who studies galaxy formation and evolution.
"But the value and the thing that is absolutely mind blowing is to step back and take them in all at once."
Distant weird galaxies
The farther you travel through time, the more unusual galaxies become.
Euclid will eventually be able to gaze about 10 billion years into the past, detecting the faint light of very distant galaxies.
In the first image drop, it's taking a look at an unusual galaxy closer to home.
This is the irregular dwarf galaxy NGC 6822, which is about 1.6 million light-years from Earth. It may not look like much, but it's a fascinating object of observation.
It was first detected by Edwin Hubble, an astronomer renowned for getting eyes on the cosmos, back in 1925.
Revealing a 'hidden galaxy'
Eleven million light-years from Earth resides Caldwell 5.
It might sound like the destination for Starfleet in a Star Trek film, but this galaxy has long remained out of the limelight.
Also known as "the Hidden Galaxy", our view of Caldwell 5 is obscured by the dusty, gaseous disc of the Milky Way.
Thanks to Euclid's near-infrared camera, astronomers are able to pull back that cosmic curtain and measure some of the light emanating from the galaxy.
"This image might look normal, as if every telescope can make such an image, but that is not true," noted Leslie Hunt, an astronomer at the National Institute for Astrophysics in Italy, in an ESA press release.
"What's so special here is that we have a wide view covering the entire galaxy, but we can also zoom in to distinguish single stars and star clusters."
The galaxy provides a glimpse of what our home galaxy, the Milky Way, might look like if we were to peer back at it from across the cosmos.
Revolution for astronomy
The ESA has dubbed this snapshot "a revolution for astronomy".
Its foreground shows the Perseus cluster, or Abell 426, one of the most massive objects in the known universe. It lies 240 million light-years from the Earth.
Contained within are some 1,000 galaxies. Behind those lie another 100,000 galaxies.
Why are these galaxies clustering together? One might reason that gravity is pulling all these objects together, locking them in a never-ending space two-step.
But gravity alone does not explain why Perseus appears as it does. Astronomers suggest the influence of dark matter and dark energy has a hold on the galaxies in Perseus.
Euclid will allow scientists to study how these galaxies are shaped in unprecedented detail, detecting very small changes that could hint at changes in the distribution of dark matter.
Those changes are visible thanks to gravitational lensing. Massive galaxies in the foreground bend the light of the galaxies in the background.
"That will directly give you a gravitational measure of the dark matter that holds that cluster together," Dr Taylor said.
If you study the image, you can see hints of galaxies that are warped and curved due to this effect.
So how is this different to James Webb?
Euclid has two chief advantages over the JWST.
"The thing that makes Euclid amazing is its speed. It's fast," Dr Taylor said.
At any moment, JWST can focus on small portions of the sky, while Euclid will focus on large swaths.
It's not quite as sensitive as JWST, but it makes up for it by looking at huge regions of space.
"Euclid is a small telescope but it has a very large field of view," said Tayyaba Zafar, an astronomer at Macquarie University studying the interstellar medium.
"It can cover 100 times more sky than JWST."
The ESA says this will enable Euclid to "create the largest cosmic 3D map ever made".
The first images provide a tantalising glimpse of just how impressive that map will be.
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