Extract from ABC News
The deepest view of the cosmos ever captured has been released by US President Joe Biden.
The first image from the $13 billion James Webb Space Telescope is the farthest humanity has ever seen in both time and distance, closer to the dawn of time and the edge of the universe.
Released at a White House event, the "deep field" image is filled with lots of stars, with massive galaxies in the foreground and faint and extremely distant galaxies peeking through here and there.
"What you are seeing are galaxies shining around other galaxies whose light has been bent.
"It's just a tiny sliver of the vast universe."
The image, which was taken over 12.5 hours, is of a giant cluster of galaxies known as SMACS 0723 in the constellation of Volans.
The cluster, as it appeared about 4.6 billion years ago, acts like a magnifying glass to the galaxies beyond.
The mass of the cluster warps space and bends the light from more distant and older galaxies from the early universe.
"It's really striking," astrophysicist Robin Cook from the University of Western Australia said.
The bright stars with the hexagonal shape are closer stars from our own Milky Way.
Then, in the distance is the warped curves of the galaxy cluster, which provides a powerful lens into the much older galaxies behind it.
"If this galaxy group wasn't in between, we wouldn't be able to see these galaxies because they'd just be too faint," Dr Cook said.
"But it's the fact that they're magnifying the light, boosting how bright they are that we actually get a chance to see these very, very distant, very faint galaxies."
Astrophysicist Karl Glazebrook of Swinburne University said the “amazing” image provided far more detail about the galaxy cluster and the older galaxies sitting behind than was ever possible using the Hubble Telescope.
For example, beads of colour in the image could be early star clusters.
"We are seeing a wide range of colours we haven’t seen before in the early universe," Professor Glazebrook said.
The other thing Professor Glazebrook found interesting was the diverse range of galaxy shapes in the early universe.
“The larger background galaxies are quite smooth. That's different to our view of SMACS from Hubble.
Just how complicated though, will make much more work for scientists to tease out.
Data for first direct view of the early universe, on par with Hubble's Ultra Deep Field image, should come down from the telescope at the end of this week in the first batch of science data, Professor Glazebrook said.
Then, in the coming weeks, Professor Glazebrook and Dr Cook will be crunching more data from the JWST, working out how early the galaxies are in this and other images, as well as looking for galaxies that don’t conform to the cosmic picture as we currently understand it.
Hellish alien planet among tomorrow's images
Today's image will be followed tomorrow (12:30am AEST) by the release of four more galactic beauty shots from the telescope's initial outward gazes:
- 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 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 prior to the release of the first image.
Launched on Christmas Day last year, the 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.
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