The James Webb Telescope: What will scientists learn?

A composite image of the Cosmic Cliffs in the Carina Nebula, created with NIRCam and MIRI instrument data from Nasa's James Webb Space Telescope. Nasa, ESA, CSA, STScI, Webb ERO Production Team/Handout via Reuters

A composite image of the Cosmic Cliffs in the Carina Nebula, created with NIRCam and MIRI instrument data from Nasa's James Webb Space Telescope. Nasa, ESA, CSA, STScI, Webb ERO Production Team/Handout via Reuters

Published Jul 17, 2022

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by Issam Ahmed

Washington: The James Webb Space Telescope's first images aren't just breathtaking -- they contain a wealth of scientific insights and clues that researchers are eager to pursue.

Here are some of the things scientists hope to learn.

Into the deep

Webb's first image, released on Monday, delivered the deepest and sharpest infrared image of the distant universe, "Webb's First Deep Field."

The white circles and ellipses are from the galaxy cluster in the foreground called SMACS 0723, as it appeared more than 4.6 billion years ago – roughly when our Sun formed too.

The reddish arcs are from light from ancient galaxies that has travelled more than 13 billion years, bending around the foreground cluster, which acts as a gravitational lens.

PICTURE SHOWS: This landscape of “mountains” and “valleys” speckled with glittering stars is the edge of a nearby, young, star-forming region called NGC 3324 in the Carina Nebula. Captured in infrared light by Nasa’s new James Webb Space Telescope. Handout via Reuters

Nasa astrophysicist Amber Straughn said she was struck by "the astounding detail that you can see in some of these galaxies".

"They just pop out! There is so much more detail, it's like seeing in hi-def."

Plus, added Nasa astrophysicist Jane Rigby, the image could teach us more about mysterious dark matter, which is thought to comprise 85% of matter in the universe –and was the main cause of the cosmic magnifying effect.

The composite image, which required a 12.5 hour exposure time, is considered a practice run. Given longer exposure time, Webb should break all-time distance records by gazing back to the first few hundred million years after the Big Bang, 13.8 billion years ago.

The hunt for habitable planets

Webb captured the signature of water, along with previously undetected evidence of clouds and haze, in the atmosphere surrounding a hot, puffy gas giant planet called WASP-96 b that orbits a distant star like our Sun.

PICTURE SHOWS: This deep field, taken by Webb’s Near-Infrared Camera (NIRCam), is a composite made from images at different wavelengths, totaling 12.5 hours – achieving depths at infrared wavelengths beyond the Hubble Space Telescope’s deepest fields, which took weeks. The image shows the galaxy cluster SMACS 0723 as it appeared 4.6 billion years ago. The combined mass of this galaxy cluster acts as a gravitational lens, magnifying much more distant galaxies behind it.STORY COPY:Nasa’s James Webb Space Telescope has delivered the deepest and sharpest infrared image of the distant universe so far. Webb’s First Deep Field is galaxy cluster SMACS 0723, and it is teeming with thousands of galaxies – including the faintest objects ever observed in the infrared.Webb’s image is approximately the size of a grain of sand held at arm’s length, a tiny sliver of the vast universe. The combined mass of this galaxy cluster acts as a gravitational lens, magnifying more distant galaxies, including some seen when the universe was less than a billion years old. This deep field, taken by Webb’s Near-Infrared Camera (NIRCam), is a composite made from images at different wavelengths, totalling 12.5 hours – achieving depths at infrared wavelengths beyond the Hubble Space Telescope’s deepest fields, which took weeks. And this is only the beginning. Researchers will continue to use Webb to take longer exposures, revealing more of our vast universe.Webb’s NIRCam has brought distant galaxies into sharp focus – they have tiny, faint structures that have never been seen before, including star clusters and diffuse features.Light from these galaxies took billions of years to reach us. We are looking back in time to within a billion years after the big bang when viewing the youngest galaxies in this field. The light was stretched by the expansion of the universe to infrared wavelengths that Webb was designed to observe. Researchers will soon begin to learn more a

The telescope achieved this by analysing starlight filtered through the planet's atmosphere as it moves across the star, to the unfiltered starlight detected when the planet is beside the star – a technique called spectroscopy that no other instrument can do at the same detail.

WASP-96 b is one of more than 5 000 confirmed exoplanets in the Milky Way. But what really excites astronomers is the prospect of pointing Webb at smaller, rocky worlds, like our own Earth, to search for atmospheres and bodies of liquid water that could support life.

Death of a star

Webb's cameras captured a stellar graveyard, in the Southern Ring Nebula, revealing the dim, dying star at its centre in clear detail for the first time, and showing that it is cloaked in dust.

Astronomers will use Webb to delve deeper into specifics about "planetary nebulae" like these, which spew out clouds of gas and dust.

The nebulae will eventually also lead to rebirth.

The gas and cloud ejection stops after some tens of thousands of years, and once the material is scattered in space, new stars can form.

A cosmic dance

Stephan's Quintet, a grouping of five galaxies, is in the constellation Pegasus.

Webb was able to pierce through the clouds of dust and gas at the centre of the galaxy to glean new insights, such as the velocity and composition of outflows of gas near its supermassive black hole.

Four of the galaxies are close together and locked in a "cosmic dance" of repeated close encounters.

By studying it, "you learn how the galaxies collide and merge," said cosmologist John Mather, adding our own Milky Way was probably assembled out of 1 000 smaller galaxies.

Understanding the black hole better will also give us greater insights into Sagittarius A*, the black hole at the centre of the Milky Way, which is shrouded in dust.

Stellar nursey

Perhaps the most beautiful image is that of the "Cosmic Cliffs" from the Carina Nebula, a stellar nursery.

Here, for the first time, Webb has revealed previously invisible regions of star formation, which will tell us more about why stars form with certain mass, and what determines the number that form in a certain region.

NASA’s James Webb Space Telescope has delivered the deepest and sharpest infrared image of the distant universe so far. Webb’s First Deep Field is galaxy cluster SMACS 0723, and it is teeming with thousands of galaxies – including the faintest objects ever observed in the infrared.Webb’s image is approximately the size of a grain of sand held at arm’s length, a tiny sliver of the vast universe. The combined mass of this galaxy cluster acts as a gravitational lens, magnifying more distant galaxies, including some seen when the universe was less than a billion years old. This deep field, taken by Webb’s Near-Infrared Camera (NIRCam), is a composite made from images at different wavelengths, totaling 12.5 hours – achieving depths at infrared wavelengths beyond the Hubble Space Telescope’s deepest fields, which took weeks. And this is only the beginning. Researchers will continue to use Webb to take longer exposures, revealing more of our vast universe.Webb’s NIRCam has brought distant galaxies into sharp focus – they have tiny, faint structures that have never been seen before, including star clusters and diffuse features.Light from these galaxies took billions of years to reach us. We are looking back in time to within a billion years after the big bang when viewing the youngest galaxies in this field. The light was stretched by the expansion of the universe to infrared wavelengths that Webb was designed to observe. Researchers will soon begin to learn more about the galaxies’ masses, ages, histories, and compositions.Other features include the prominent arcs in this field. The powerful gravitational field of a galaxy cluster can bend the light rays from more distant galaxies behind it, just as a magnifying glass bends and warps images. Stars are also captured with prominent diffraction spikes, as they appear brighter at shorter wavelengths.Webb’s MIRI image offers a kaleidoscope of colors and highlights where the dust is – a major

They might look like mountains, but the tallest of the craggy peaks were seven light years high, and the yellow structures were made from huge hydrocarbon molecules, said Webb project scientist Klaus Pontoppidan.

In addition to being the stuff of stars, nebular material could also be where we come from.

"This may be the way that the universe is transporting carbon, the carbon that we're made of, to planets that may be habitable for life," he said.

The great unknown

Perhaps most exciting of all was journeying into the unknown, said Straughn.

Hubble played a key role in discovering that dark energy was causing the universe to expand at an ever-growing rate, "so it's hard to imagine what we might learn with this 100 times more powerful instrument".

AFP