Get ready to travel back into the early universe this week as scientists prepare to reveal the most-detailed snapshots ever taken of our cosmos.
Four full-colour images from the new James Webb Telescope will be released, with US President Joe Biden unveiling the first one at 7am AEST on Tuesday.
The rest will be released at 12:30am (AEST) on Wednesday.
One of the images promises to catapult us deeper back in time than we have ever seen before.
"We're going to give humanity a new view of the cosmos," NASA administrator Bill Nelson said.
The image will reveal some of the earliest galaxies and stars that formed after the Big Bang 13.8 billion years ago.
Along with the deepest view of the universe, other images the team promise will blow our minds include:
- A spectacular cloud of dust known as the Carina Nebula, where stars are being born
- A group of colliding galaxies called Stephan's Quintet
- A massive bubble of gas known as the Southern Ring Nebula surrounding a dying star
The JWST data will also include the chemical fingerprint of an atmosphere from a hellish alien planet about half the mass of Jupiter known as WASP-96b.
"What I've already seen has moved me as a scientist, as an engineer, as a human," NASA deputy administrator Pam Melroy said.
Seeing the (first) light
Launched on Christmas Day last year, the $13 billion JWST is the biggest and most powerful telescope ever put into space.
Since then, scientists from NASA, the European Space Agency, and the Canadian Space Agency have been testing its four instruments and aligning the 18 sections of its 6.5-metre gold-plated mirror.
The telescope uses infrared cameras and sensors to peer into parts of the universe with detail that no other telescope can see.
In March, the team released a crisp test-image of a star 2,000 light-years away, against a background of ancient galaxies billions of light-years away, providing the first taste of what JWST could do.
Then in June, a micro meteorite dinged one of the segments, just before the telescope started taking its first set of full-resolution images we're about to see.
Despite this, scientists say it is performing twice as well as expected.
So what do we know about the galaxies, stars and planets the team has selected to dazzle us with? And how spectacular will these new images be?
To understand that, we need to look back at some images taken by the Hubble Space Telescope over the years.
Travelling back into deep time
As the universe expands, light from the earliest galaxies and stars is stretched or shifted to longer, redder wavelengths as it travels towards us.
The earliest galaxies we've been able to see so far existed between 400 million to 800 million years after the Big Bang.
These galaxies were captured by the Hubble Space Telescope in a famous image called the Ultra Deep Field.
The image, which was taken more than 20 years ago, took two weeks to create and captured more than 10,000 ancient galaxies in the constellation of Fornax.
The JWST can detect objects in much longer wavelengths than the Hubble, so it can peer further back in time, and promises to fill in the critical gap between the Big Bang and the earliest galaxies and stars detected by Hubble.
To do this, the team has chosen a patch of sky known as SMACS 0723 in the constellation of Volans.
This area contains a number of large galaxy clusters that sit between us and more distant galaxies and stars.
The mass of these clusters acts like a magnifying glass, distorting space and amplifying light coming from further away.
In May, scientists created one of the deepest images of the universe ever taken while testing out the telescope's fine guidance system.
The image was taken using 72 exposures over 32 hours.
The full-resolution images taken by the telescope's main instruments promise to look even more spectacular.
The Carina Nebula
The Carina Nebula is located approximately 7,600 light-years away in the southern constellation of Carina.
It is one of the largest and brightest stellar nurseries in the sky, with pillars of dust several light-years tall filled with massive young stars.
A set of Hubble images released in 2018 show what it looks like in optical light (the light we see with our eyes), and in near-infrared light, which can cut through dust in the pillars to see new stars.
The image at top of this page shows what it looks like when the optical and near-infrared images are combined into a full-colour image.
While the JWST doesn't take images in optical light, it takes longer wavelengths of infrared light than the Hubble telescope, so it will cut even further through the dust and be able to see this nebula in even more detail.
Stephan's Quintet
The JWST will also give scientists a clearer picture of how stars form when galaxies collide in a cosmic tug o' war.
Stephan's Quintet lies in the constellation of Pegasus.
It contains different types of stars ranging in age from young, blue stars to old, red stars.
Four of the five galaxies in the quintet are about 290 million light-years away.
The two galaxies ripping each other apart in the middle of the image are surrounded by a halo of gas and young stars less than 10 million years old.
The fifth galaxy, in the top left-hand corner, is about 40 million light-years away from us and is packed with bright new stars.
But as spectacular as this image is, most of the stars in the quintet are too far away for Hubble to see or shrouded in dust.
Southern Ring Nebula
The Southern Nebula lies 2,000 light-years away in the constellation of Vela.
At the heart of this massive bubble of expanding gas, known as a planetary nebula, is not one, but two stars.
The smaller star, known as a white dwarf, is all that is left of a giant red star that spewed all its gas into space before collapsing. Intense heat from the leftover small, dense star causes the gas to glow.
Peering deeper into this process will help scientists understand more about the life cycle of stars and the evolution of galaxies like our Milky Way.
When dying stars fizzle away as a planetary nebula, they may seed the cosmos with heavy elements like iron, silver and gold and contribute to the next generation of stars.
WASP-96b
Along with producing images of galaxies and stars as they've never been seen before, the JWST will also release information about the atmosphere of an exoplanet — a planet circling a star beyond our Solar System.
As a planet passes in front of its star, light passing through its atmosphere can be picked up by telescopes, which split up the light into different wavelengths.
Different wavelengths produce colours like a rainbow.
This technique, known as spectroscopy, identifies different molecules such as water, carbon dioxide, and methane, which absorb light at particular wavelengths.
This technique can also give us information about the temperature and movement of a planet.
WASP-96b is an alien planet located nearly 1,150 light-years from Earth.
Slightly larger than Jupiter, it reaches scorching temperatures of up to 1,027 degrees as it zips around its star every 3.4 days.
Gas giants like WASP-96b are among the most common types of the 5,000-plus alien planets that have been detected to date.
Observations from ground-based telescopes indicate WASP-96b is a cloudless world with a sodium-rich atmosphere.
In the future, the JWST will have its sights on Earth-like rocky planets, which are harder to study because they are smaller and not as bright.
The team says the images and data being released this week are just a snapshot of what will come from the telescope when the science mission begins its 20-year program.
And it won't be long before the record for the deepest space image is broken again.
