Extract from ABC News
It's been a year since the first full-colour image from James Webb Space Telescope (JWST) was released, and to celebrate the milestone NASA has unveiled another stunning image.
The US space agency released an image of the Rho Ophiuchi cloud complex, which is some 390 light-years away from Earth.
What is this an image of?
Stars and space dust.
The Rho Ophiuchi cloud complex is the nearest star-forming region to Earth, a NASA statement explains.
"It is a relatively small, quiet stellar nursery, but you'd never know it from Webb's chaotic close-up," NASA says.
Those red areas pictured above are jets of molecular hydrogen.
"These occur when a star first bursts through its natal envelope of cosmic dust, shooting out a pair of opposing jets into space like a newborn first stretching her arms out into the world," NASA says.
There's about 50 young stars in the image, most of them being a similar mass to the Sun or smaller.
The brightest white circle in the green-yellow swirl of cosmic dust is a star called S1, which NASA says is "significantly more massive than the Sun".
Some of the stars have shadows that suggest the presence of what's called a proto planetary disk, which sounds like a solid object but it's actually a massive ring of space dust and gas leftover from the star's formation.
"As dust grains and gas swirl around a star, gravity clumps them together," a NASA fact sheet explains.
"These clumps become larger, forming planets and moons, and eventually a solar system grows around the star.
"Our own planetary system around the Sun was formed in this same way."
So, in a way, this image is like an ultrasound of baby — except the baby is a planetary system.
"Webb's image of Rho Ophiuchi allows us to witness a very brief period in the stellar life cycle with new clarity," NASA's Klaus Pontoppidan says.
"Our own Sun experienced a phase like this, long ago, and now we have the technology to see the beginning of another star's story."
So, is this a photo?
Not exactly — the colours you see in the image above aren't as they appear to the human eye.
In fact, the image above is actually a series of separate exposures which were originally in grey scale and were beamed back to Earth.
They were taken using JWST's Near infrared Camera (NIRCam), which covers infrared wavelength range from 0.6 to 5 microns.
The equipment allows astronomers to take pictures of very faint objects around a central bright object, a NASA fact sheet says.
It works by blocking out the brighter object's light which makes it possible to capture the dimmer object nearby.
"Just like shielding the Sun from your eyes with an upraised hand can allow you to focus on the view in front of you," NASA explains.
Each image was taken using a different filter to capture different wavelengths — and each filter has been assigned a different colour.
The colour comes form layering all of these images on top of each other.
Here are the colours used to create the image above:
How big is the complex?
NASA says it's 0.7 light-years across.
That might not sound like much, but one light-year equals about 9.4 trillion kilometres.
So that image is roughly 6.58 trillion kilometres across — which is how there can be so many Sun-like stars in one image.
Can I zoom in?
The image above is compressed to a view that will allow our website to load it quickly.
But you can see a zoomable image on the NASA website to get more detail.
Why is JWST such a big deal?
It's humanity's most powerful space telescope yet.
It was created in order to take the place of the Hubble Space Telescope.
Hubble produced some incredible images in its time but, as the JWST is significantly larger and capable of observing infrared light, it'll give us even better vision of what's beyond our world.
JWST was first suggested way back in 1989 and was finally launched into space on December 25, 2021.
"In just one year, the James Webb Space Telescope has transformed humanity's view of the cosmos, peering into dust clouds and seeing light from faraway corners of the universe for the very first time," NASA Administrator Bill Nelson says.
"Every new image is a new discovery, empowering scientists around the globe to ask and answer questions they once could never dream of.
"Webb is an investment in American innovation but also a scientific feat made possible with NASA's international partners that share a can-do spirit to push the boundaries of what is known to be possible.
"Thousands of engineers, scientists, and leaders poured their life's passion into this mission, and their efforts will continue to improve our understanding of the origins of the universe – and our place in it."
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