Webb Telescope: What Will Scientists Learn?

James Webb telescope Jonathan WALTER AFP
James Webb telescope Jonathan WALTER AFP
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Webb Telescope: What Will Scientists Learn?

James Webb telescope Jonathan WALTER AFP
James Webb telescope Jonathan WALTER AFP

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 now hope to learn, AFP said.

- Into the deep -
Webb's first image, released Monday, delivered the deepest and sharpest infrared image of the distant universe so far, "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 traveled more than 13 billion years, bending around the foreground cluster, which acts as a gravitational lens.

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 high-def."

Plus, added NASA astrophysicist Jane Rigby, the image can teach us more about mysterious dark matter, which is thought to comprise 85 percent of matter in the universe -- and is 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.

The telescope achieved this by analyzing 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 center 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.

These 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 located in the constellation Pegasus.

Webb was able to pierce through the clouds of dust and gas at the center 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 center 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.

They may look like mountains, but the tallest of the craggy peaks are seven light years high, and the yellow structures are 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 is journeying into the unknown, said Straughn.

Hubble played a key role in discovering that dark energy is 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."



Alien Planet Lashed by Huge Flares from its 'Angry Beast' Star

File Photo: An imagined view of the three planets orbiting an ultracool dwarf star just 40 light-years from Earth discovered using a specialist telescope at ESO's La Silla Observatoryin Chile. ESO/M. Kornmesser/N. Risinger
File Photo: An imagined view of the three planets orbiting an ultracool dwarf star just 40 light-years from Earth discovered using a specialist telescope at ESO's La Silla Observatoryin Chile. ESO/M. Kornmesser/N. Risinger
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Alien Planet Lashed by Huge Flares from its 'Angry Beast' Star

File Photo: An imagined view of the three planets orbiting an ultracool dwarf star just 40 light-years from Earth discovered using a specialist telescope at ESO's La Silla Observatoryin Chile. ESO/M. Kornmesser/N. Risinger
File Photo: An imagined view of the three planets orbiting an ultracool dwarf star just 40 light-years from Earth discovered using a specialist telescope at ESO's La Silla Observatoryin Chile. ESO/M. Kornmesser/N. Risinger

Scientists are tracking a large gas planet experiencing quite a quandary as it orbits extremely close to a young star - a predicament never previously observed.

This exoplanet, as planets beyond our solar system are called, orbits its star so tightly that it appears to trigger flares from the stellar surface - larger than any observed from the sun - reaching several million miles (km) into space that over time may strip much of this unlucky world's atmosphere, Reuters reported.

The phenomenon appears to be caused by the planet's interaction with the star's magnetic field, according to the researchers. And this star is a kind known to flare, especially when young.

"A young star of this type is an angry beast, especially if you're sitting as close up as this planet does," said Netherlands Institute for Radio Astronomy astrophysicist Ekaterina Ilin, lead author of the study published in the journal Nature.

The star, called HIP 67522, is slightly more massive than the sun and is located about 407 light-years from Earth in the constellation Centaurus. A light-year is the distance light travels in a year, 5.9 trillion miles (9.5 trillion km).

This star and planet, as well as a second smaller gas planet also detected in this planetary system, are practically newborns. Whereas the sun and our solar system's planets are roughly 4.5 billion years old, this star is about 17 million years old, with its planets slightly younger.

The planet, named HIP 67522 b, has a diameter almost the size of Jupiter, our solar system's largest planet, but with only 5% of Jupiter's mass. That makes it one of the puffiest exoplanets known, with a consistency reminiscent of cotton candy (candy floss).

It orbits five times closer to its star than our solar system's innermost planet Mercury orbits the sun, needing only seven days to complete an orbit.

A flare is an intense eruption of electromagnetic radiation emanating from the outermost part of a star's atmosphere, called the corona. So how does HIP 67522 b elicit huge flares from the star? As it orbits, it apparently interacts with the star's magnetic field - either through its own magnetic field or perhaps through the presence of conducting material such as iron in the planet's composition.

"We don't know for sure what the mechanism is. We think it is plausible that the planet moves within the star's magnetic field and whips up a wave that travels along magnetic field lines to the star. When the wave reaches the stellar corona, it triggers flares in large magnetic field loops that store energy, which is released by the wave," Ilin said.

"As it moves through the field like a boat on a lake, it creates waves in its wake," Ilin added. "The flares these waves trigger when they crash into the star are a new phenomenon. This is important because it had never been observed before, especially at the intensity detected."

The researchers believe it is a specific type of wave called an Alfvén wave, named for 20th century Swedish physicist and Nobel Prize laureate Hannes Alfvén, that propagates due to the interaction of magnetic fields.

The flares may heat up and inflate the planet's atmosphere, which is dominated by hydrogen and helium. Being lashed by these flares could blast away lighter elements from the atmosphere and reduce the planet's mass over perhaps hundreds of millions of years.

"At that time, it will have lost most if not all the light elements, and become what's called a sub-Neptune - a gas planet smaller than Neptune," Ilin said, referring to the smallest of our solar system's gas planets.

The researchers used observations by two space telescopes: NASA's TESS, short for Transiting Exoplanet Survey Satellite, and the European Space Agency's CHEOPS, short for CHaracterising ExOPlanet Satellite.

The plight of HIP 67522 b illustrates the many circumstances under which exoplanets exist.

"It is certainly no sheltered youth for this planet. But I am not sad about it. I enjoy diversity in all things nature, and what this planet will eventually become - perhaps a sub-Neptune rich in heavy elements that did not evaporate - is no less fascinating than what we observe today."