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    Default Re: The Power Of The James Webb Telescope in Space To Be Launched in 2021

    • Mind-Blowing Capabilities of the James Webb Space Telescope:
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    Default Re: The Power Of The James Webb Telescope in Space To Be Launched in 2021

    • Are We Alone in The Galaxy? Brian Cox on Alien Life:
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    Default Re: The Power Of The James Webb Telescope in Space To Be Launched in 2021

    • James Webb Telescope Launch: 30 Days of Absolute Horror:
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    Default Re: The Power Of The James Webb Telescope in Space To Be Launched in 2021

    Quote Posted by ExomatrixTV (here)
    • James Webb Telescope Launch: 30 Days of Absolute Horror:
    I'm getting stressful/anxious now.. hopefully it's all minor issues and just being meticulous. I really want this thing to work !
    To the mind that is still, the whole universe surrenders. -Lao Tzu

    I must not fear. Fear is the mind-killer.

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    Default Re: The Power Of The James Webb Telescope in Space To Be Launched in 2021

    • Inside the James Webb Space Telescope’s Orbit Around the Sun:


    ¤=[Post Update]=¤

    • Why Did The James Webb Telescope Cost So Much?
    Last edited by ExomatrixTV; 1st December 2021 at 13:47.
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    Lightbulb Re: The Power Of The James Webb Telescope in Space To Be Launched in 2021

    • Red Dwarf Exoplanets may be safe from Superflares
    • Red Dwarf Exoplanets Could Be Habitable Because They Dodge Deadly Radiation From Stars
    • Newfound Super-Earth has speedy orbit around Red Dwarf Star

    If JWST shows definite evidence (signs/signatures) of biological life on multiple exoplanets and/or is much better finding 10,000s new exo-planets nearby >>> most likely most of them are near Red Dwarfs that are much older than our Sun is thus having enough time to evolve longer than Earth is.
    • Plus in corroboration (help) from the biggest Radio & Gamma Telescopes worldwide pointing at all new found exp-planets is a given!
    I am very exited about the bigger picture as it will shift our human attitude/paradigm & collective human consciousness also what is possible dealing with much more real UFO research ... it is all connected in my view.
    • The current list of Exoplanets that are closest to be "Earth-like" can all be examined with a "second look" using JWST
    cheers,
    John Kuhles aka 'ExomatrixTV'
    December 1st, 2021
    Last edited by ExomatrixTV; 1st December 2021 at 19:51.
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    Lightbulb Re: The Power Of The James Webb Telescope in Space To Be Launched in 2021

    • Signs of extra terrestrial life could be found in the next two to three years, astronomers claim
    A newly discovered class of life-supporting exoplanets could bring our search for alien life tantalisingly close, Cambridge study suggests.

    When it comes to hunting down signs of life on distant planets astronomers have typically played it safe. They’ve looked for Earth-sized planets, with Earth-like surface temperatures, and Earth-like atmospheres.

    But now, a team of researchers from the University of Cambridge have identified a new class of habitable planets that could change the game completely. Dubbed ‘Hycean’ planets – meaning hot, ocean-covered planets with hydrogen-rich atmospheres – the newly identified exoplanets are far greater in number and easier to spot than Earth-like planets.

    And specifically hunting for Hycean planets could lead to us discovering biosignatures of life outside our Solar System within the next two or three years, they say.

    Read more about exoplanets:
    “Hycean planets open a whole new avenue in our search for life elsewhere,” said study leader Dr Nikku Madhusudhan from Cambridge’s Institute of Astronomy.

    “Essentially, when we’ve been looking for these various molecular signatures, we have been focusing on planets similar to Earth, which is a reasonable place to start. But we think Hycean planets offer a better chance of finding several trace biosignatures.”

    Hycean planets can be up to 2.6 times larger than Earth and have atmospheric temperatures as high as 200ºC. However, their oceanic conditions could be similar to Earth’s and so could potentially harbour microbial life. A significant proportion of the exoplanets discovered so far fall into this category.

    The larger sizes, higher surface temperatures and hydrogen-rich atmospheres of Hycean planets also make their atmospheric signatures much easier to detect than Earth-like planets.

    When looking for signs of life on other planets astronomers look at so-called biosignatures such as oxygen, ozone, methane and nitrous oxide, which are all present on Earth. There are also a number of other biomarkers, such as methyl chloride and dimethyl sulphide, that could suggest the existence of life on planets with hydrogen-rich atmospheres where oxygen and ozone may not be as abundant.

    “A biosignature detection would transform our understanding of life in the Universe,” said Madhusudhan. “We need to be open about where we expect to find life and what form that life could take, as nature continues to surprise us in often unimaginable ways.”

    The team has identified a number of Hycean planets between 35 and 150 light-years away that they hope will be prime targets for the next generation of space telescopes, such as the James Webb Space Telescope (JWST), which is due to be launched later this year.


    • What does it mean if an exoplanet is ‘habitable’?
    All forms of life that we know of depend on one critical component: liquid water. So, in the search for life, astronomers focus on planets where liquid water could exist, which they call ‘habitable’.

    Every star has a ‘habitable zone’, also called the ‘Goldilocks zone’, where it is not too hot and not too cold. A planet in the habitable zone gets the right amount of energy from the star to support liquid water. Any closer in to the star and water would boil, and any further out and it would freeze.
    However, this doesn’t guarantee that liquid water would exist on a planet in the habitable zone. The planet’s atmosphere could be too thick, raising the temperature even higher. And even if liquid water does exist on the planet, habitable doesn’t mean inhabited.

    Read more:
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    Thumbs up Re: The Power Of The James Webb Telescope in Space To Be Launched in 2021

    An incident during processing earlier this month didn't cause any serious problems, NASA determined.


    Everything has to go right for the James Webb Space Telescope.


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    Default Re: The Power Of The James Webb Telescope in Space To Be Launched in 2021

    We have to get a new phone every two years because it's already outdated. How is it that after 30+ years, is the James Webb Telescope is still relevant?


    --o-O-o--

    • Artist’s impression of exoplanet KELT-11 b. Credit: Impression by Léa Changeat., Author provided

    Do you know what the Earth's atmosphere is made of? You'd probably remember it's oxygen, and maybe nitrogen. And with a little help from Google you can easily reach a more precise answer: 78% nitrogen, 21% oxygen and 1% Argon gas. However, when it comes to the composition of exo-atmospheres—the atmospheres of planets outside our solar system—the answer is not known. This is a shame, as atmospheres can indicate the nature of planets, and whether they can host life.

    As exoplanets are so far away, it has proven extremely difficult to probe their atmospheres. Research suggests that artificial intelligence (AI) may be our best bet to explore them—but only if we can show that these algorithms think in reliable, scientific ways, rather than cheating the system. Now our new paper, published in The Astrophysical Journal, has provided reassuring insight into their mysterious logic.
    Astronomers typically exploit the transit method to investigate exoplanets, which involves measuring dips in light from a star as a planet passes in front of it. If an atmosphere is present on the planet, it can absorb a very tiny bit of light, too. By observing this event at different wavelengths—colors of light—the fingerprints of molecules can be seen in the absorbed starlight, forming recognizable patterns in what we call a spectrum. A typical signal produced by the atmosphere of a Jupiter-sized planet only reduces the stellar light by ~0.01% if the star is Sun-like. Earth-sized planets produce 10–100 times lower signals. It's a bit like spotting the eye color of a cat from an aircraft.

    In the future, the James Webb Space Telescope (JWST) and the Ariel Space Mission, both probes that will investigate exoplanets from their orbit in space, will help by providing high-quality spectra for thousands of exo-atmospheres. But while scientists are excited about this, the latest research suggests it may be tricky. Due to the complex nature of atmospheres, the analysis of a single transiting planet may take days or even weeks to complete.

    Naturally, researchers have started to look for alternative tools. AI are renowned for their ability to assimilate and learn from a large amount of data and their superb performance on different tasks once trained. Scientists have therefore attempted to train AI to predict the abundance of various chemical species in atmospheres.

    Current research has established that AIs are well-suited for this task. However, scientists are meticulous and skeptical, and to prove this is really the case, they want to understand how AIs think.



    How an AI’s predictions works for blurred cat image. Author provided
    • Peeking inside the black box
    In science, a theory or a tool cannot be adopted if it is not understood. After all, you don't want to go through the excitement of discovering life on an exoplanet, just to realize it is simply a "glitch" in the AI. The bad news is that AIs are terrible at explaining their own findings. Even AI experts have a hard time identifying what causes the network to provide a given explanation. This disadvantage has often prevented the adoption of AI techniques in astronomy and other scientific fields.

    We developed a method that allows us a glimpse into the decision-making process of AI. The approach is quite intuitive. Suppose an AI has to confirm whether an image contains a cat. It would presumably do this by spotting certain characteristics, such as fur or face shape. To understand which characteristics it is referencing, and in what order, we could blur parts of the cat's image and see if it still spots that it is a cat.
    This is exactly what we did for an exoplanet-probing AI by "perturbing," or changing, regions of the spectrum. By observing how the AI's predictions on the abundances of exoplanet molecules changed (say water in the atmosphere) when each region was doctored, we started to build a "picture" of how the AI thought, such as which regions of the spectrum it used for deciding the level of water in the atmosphere.

    Reassuringly for us astronomers, we found that a well-trained AI relies heavily on physical phenomena, such as unique spectroscopic fingerprints—just like an astronomer would. This may come as no surprise, after all, where else can the AI learn it from? In fact, when it comes to learning, AI is not so different from a cheeky high-school student—it will try its best to avoid the hard way (such as understanding difficult mathematical concepts) and find any shortcuts (such as memorizing the mathematical formulae without understanding why) in order to get the correct answer. If the AI made predictions based on memorizing every single spectrum it had come across, that would deeply undesirable. We want the AI to derive its answer from the data, and perform well on unknown data, not just the training data for which there is a correct answer.



    We can combine features highlighted by the AI together with the original image to produce what we called a sensitivity map which outlines the areas it is looking closely at. Author provided

    This finding provided the first method to have a sneaky peek into so-called "AI black-boxes," allowing us to evaluate what the AIs have learnt. With these tools, researchers now can not only use AIs to speed up their analysis of exo-atmospheres, but they can also verify that their AI uses well-understood laws of nature.

    That said, it's too early to claim that we fully understand AIs. The next step is to work out precisely how important each concept is, and how it gets processed into decisions.
    The prospect is exciting for AI experts, but even more so for us scientists. AI's incredible learning power originates from its ability to learn a "representation," or pattern, from the data—a technique similar to how physicists have discovered laws of nature in order to better understand our world. Having access to the minds of AI may therefore grant us the opportunity to learn new, undiscovered laws of physics.
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    Default Re: The Power Of The James Webb Telescope in Space To Be Launched in 2021

    • How NASA’s Webb Telescope Will Transform Our Place in the Universe:

    NASA's James Webb Space Telescope is the most powerful telescope in the history of humanity, and one of the most ambitious engineering projects ever attempted. It will witness the birth of stars and galaxies at the edge of time and probe alien skies for signs of life. In this new documentary from Quanta, JWST’s lead scientists and engineers discuss what inspired the telescope, how it was built, the extraordinary challenges it will face upon launch, and its potential discoveries.

    To look back in time at the cosmos’s infancy and witness the first stars flicker on, you must first grind a mirror as big as a house. Its surface must be so smooth that, if the mirror were the scale of a continent, it would feature no hill or valley greater than ankle height. Only a mirror so huge and smooth can collect and focus the faint light coming from the farthest galaxies in the sky — light that left its source long ago and therefore shows the galaxies as they appeared in the ancient past, when the universe was young. The very faintest, farthest galaxies we would see still in the process of being born, when mysterious forces conspired in the dark and the first crops of stars started to shine.

    But to read that early chapter in the universe’s history — to learn the nature of those first, probably gargantuan stars, to learn about the invisible matter whose gravity coaxed them into being, and about the roles of magnetism and turbulence, and how enormous black holes grew and worked their way into galaxies’ centers — an exceptional mirror is not nearly enough.

    The reason no one has seen the epoch of galaxy formation is that the ancient starlight, after traveling to us through the expanding fabric of space for so many billions of years, has become stretched. Ultraviolet and visible light spewed by the farthest stars in the sky stretched to around 20-times-longer wavelengths during the journey here, becoming infrared radiation. But infrared light is the kind of atom-jiggling light we refer to as heat, the same heat that radiates from our bodies and the atmosphere and the ground beneath our feet. Alas, these local heat sources swamp the pitiful flames of primeval stars. To perceive those stars, the telescope with its big perfect mirror has to be very cold. It must be launched into space.

    The catch is that a house-size mirror is too large to fit in any rocket fairing. The mirror, then, must be able to fold up. A mirror can only fold if it’s segmented — if, instead of a single, uninterrupted surface, it’s a honeycomb array of mirror segments. But in order to collectively create sharp images, the mirror segments, after autonomously unfolding in space, must be in virtually perfect alignment. Spectacularly precise motors are needed to achieve a good focus — motors that can nudge each mirror segment by increments of half the width of a virus until they’re all in place.



    The ability to see faint infrared sources doesn’t just grant you access to the universe’s formative chapter — roughly the period from 50 million to 500 million years after the Big Bang — it would reveal other, arguably just as significant aspects of the cosmos as well, from properties of Earth-size planets orbiting other stars to the much-contested rate at which space is expanding. But for the telescope to work, one more element is required, beyond a flawless mirror that autonomously unfolds and focuses after being shot into the sky.

    Even in outer space, the Earth, moon and sun all still heat the telescope too much for it to perceive the dim twinkle of the most distant structures in the cosmos. Unless, that is, the telescope heads for a particular spot four times farther away from Earth than the moon called Lagrange point 2. There, the moon, Earth and sun all lie in the same direction, letting the telescope block out all three bodies at once by erecting a tennis court-size sunshield. Shaded in this way, the telescope can finally enter a deep chill and at long last detect the feeble heat of the cosmic dawn. The sunshield is both an infrared telescope’s only hope and its Achilles heel.

    In order to unfurl to large enough proportions without weighing down a rocket, the sunshield must consist of thin fabric. (The whole observatory, for that matter, including its mirrors, cameras and other instruments, its transmitters and its power sources, must have only about 2% of the typical mass of a large ground-based telescope.) Nothing about building a giant yet lightweight infrared-sensing spacecraft is easy, but the unavoidable use of fabric makes it an inherently risky affair. Fabric is, engineers say, “nondeterministic,” its movements impossible to perfectly control or predict. If the sunshield snags as it unfurls, the whole telescope will turn into space junk.

    Currently, the telescope — which has, incredibly, been built — is folded up and ready to be placed atop an Ariane 5 rocket. The rocket is scheduled for liftoff from Kourou, French Guiana, on December 22, more than 30 years after its payload, the James Webb Space Telescope (JWST), was first envisioned and sketched. The telescope is 14 years behind schedule and 20 times over budget. “We’ve worked as hard as we could to catch all of our mistakes and test and rehearse,” said John Mather, the Nobel Prize-winning astrophysicist who has been chief scientist of the NASA-led project for 25 years. Now, he said, “we’re going to put our zillion-dollar telescope on top of a stack of explosive material” and turn things over to fate. The assembled telescope stands tall with its mirror folded at Northrop Grumman’s facility in California. Northrop Grumman.

    The story of JWST’s development over the past three decades has paralleled the tremendous progress we’ve made in our understanding of the cosmos, not least because of Webb’s predecessors. With the Hubble Space Telescope, we’ve learned that stars, galaxies and supermassive black holes existed far earlier in cosmic history than anyone expected, and that they have since undergone radical change. We’ve learned that dark matter and dark energy sculpt the cosmos. With the Kepler telescope and others, we’ve seen that all manner of planets decorate galaxies like baubles on Christmas trees, including billions of potentially habitable worlds in our Milky Way alone. These discoveries have raised questions that the James Webb Space Telescope can address. Astronomers also hope that, as with other telescopes, its sightings will raise new questions. “Every time we build new equipment,” Mather said, “we get a surprise.”

    The launch will begin what the astronomer Natalie Batalha called “six months of pins and needles,” as the staggeringly complex telescope will attempt to unfold and focus itself in hundreds of steps. The observatory will spend a month floating 1 million miles to Lagrange point 2. On the way, it will transform into a celestial water lily, positioning its giant blossom of gold-plated mirror segments atop an even bigger silver leaf.
    “It will be our own ‘dare mighty things’ moment,” said Grant Tremblay, an astrophysicist at Harvard University who served on the telescope’s time allocation committee. “It’s going to do amazing things. We’ll be in The New York Times talking about how this is witnessing the birth of stars at the edge of time, this is one of the earliest galaxies, this is the story of other Earths.”
    “Please work,” Tremblay added, his eyes fluttering upward.
    • From Smooth to Lumpy
    The last time NASA launched an observatory of such significance — the Hubble Space Telescope, in 1990 — it was a disaster. “Absolutely catastrophic,” the veteran astronomer Sandra Faber told me. Faber was on the team that camped out at NASA’s Goddard Space Flight Center in Greenbelt, Maryland, to diagnose the disorder. From the way a star in one of Hubble’s photos looked like a ring, she and a colleague inferred that the primary mirror — the big, concave one that bounced light to a secondary mirror that then reflected it onto a camera lens — had not been ground down to quite the right concavity to focus the light; it was half a wavelength too thick around the edge. If the primary and secondary mirrors had been tested together before launch, this aberration would have been noticed, but in the rush to get the long-delayed and over-budget telescope aloft, that testing never happened.

    Some NASA leaders called for abandoning the telescope, which was already a controversial project. Instead, Senator Barbara Mikulski of Maryland secured the funds for a rescue mission. Fixing it was possible because, as an optical telescope that’s sensitive to the colors of the rainbow rather than to infrared light, Hubble can get a clear view from low-Earth orbit, only 340 miles up, instead of having to travel a million miles away. In 1993, the space shuttle docked with Hubble, and astronauts installed a sort of contact lens. The telescope would go on to revolutionize astronomy and cosmology.






    Perhaps the most important question about the universe for much of the 20th century was whether it had a beginning or if it has always been this way. For the British cosmologist Fred Hoyle and other believers in the latter “steady state” theory, “the compelling logic was simplicity,” said Jay Gallagher, an astronomer and professor emeritus at the University of Wisconsin, Madison. “That at one point something changed and the universe created matter, why did that have to be?” Hoyle, the steady-state proponent, attributed his rivals’ belief in the “Big Bang” (as he dubbed it) to the influence of the Book of Genesis.

    Then came a hiss in a radio antenna at Bell Labs in New Jersey in 1964. The hiss was generated by microwaves arriving from everywhere in the sky, exactly as predicted by the Big Bang theory. (The light was released in an early phase transition as the hot, dense universe cooled.) The discovery of the cosmic microwave background, as it was called, did not immediately end the debate — steady-state folks like Hoyle distrusted its interpretation and clung to their theory for many more decades. But for others, who recognized the afterglow of the Big Bang when they saw it, the CMB created a puzzle. The near-perfect uniformity of microwaves coming from all parts of the sky indicated that the newborn universe was astonishingly smooth — a purée of matter. “The puzzle is we see a very lumpy universe today,” said Faber, who was a graduate student studying galaxies in the late ’60s. “So the first challenge in understanding galaxies is to understand how the universe goes from smooth to lumpy.”

    Cosmologists knew atoms must have gradually clumped together because of gravity, eventually fracturing into structures like stars and galaxies. But on paper, it seemed that the growth of structure would have been extraordinarily slow. Not only was matter initially smoothly distributed, and thus pulled in no particular direction by gravity, but the expansion of space and the pressure created by light itself would both have worked to separate matter, counteracting its weak gravitational attraction.



    Enter dark matter. In the 1970s, Vera Rubin of the Carnegie Institute of Washington observed that the outskirts of galaxies rotate much faster than expected, as if whipped around by some extra, invisible source of gravity. This evidence for substantial missing matter in and around galaxies, dubbed dark matter, matched Fritz Zwicky’s 1930s observations that galaxies seem to attract each other more than they should based on their luminous matter alone. Also in the ’70s, Jim Peebles and Jerry Ostriker of Princeton University calculated that rotating galactic disks consisting only of stars, gas and dust should become unstable and swell into spheres; they posited that invisible matter must be creating a stronger gravitational well within which the visible disk rotates. In 1979, Faber and Gallagher wrote an influential paper compiling all the evidence for dark matter, which they pegged at about 90% of the matter in the universe. (The current estimate is about 85%.)

    These researchers realized that dark matter, with its substantial gravity and imperviousness to light’s pressure, could have bunched up relatively quickly in the early universe. Peebles, who won half of the 2019 Nobel Prize in Physics for his contributions to cosmology, developed a qualitative picture in which dark matter particles would have glommed together into clumps (known as halos) that then combined into bigger and bigger clumps. The British astrophysicist Simon White demonstrated this “hierarchical clustering” process in primitive 1980s computer simulations. Though visible matter was at that time too complicated to simulate, researchers surmised that the conglomerating dark matter would have brought luminous matter along for the ride: Corralled within dark matter halos, atoms would have bumped together, heated up, sunk toward the center and eventually gravitationally collapsed into stars and disk-shaped galaxies.

    Although most cosmologists became convinced of this picture, a big question was how variations in the density of matter initially set in, jump-starting the gravitational clustering process. “People had no clear idea about what were reasonable initial conditions about the formation of cosmic structure,” White, who is now retired and living in Germany, told me over Zoom. “You could run these simulations, but you didn’t have any idea what you should put in at the beginning.”

    “SPECTACULAR REALIZATION,” the cosmologist Alan Guth scrawled in his notebook in 1979. He had calculated that if space suddenly blew up like the surface of a balloon at the start of the Big Bang, this would explain how it got so huge, smooth and flat. Cosmic inflation, as Guth dubbed the primordial growth spurt, quickly became popular as a Big Bang add-on. Cosmologists soon noted that, during inflation, quantum fluctuations in the fabric of space would have gotten frozen in as space blew up, producing subtle density variations throughout the universe. The putative dense spots created by inflation could have served as the seeds of future structures.



    In 1979, Alan Guth realized that a burst of exponential expansion at the start of the Big Bang would explain several puzzling properties of the universe.

    On loan to the Adler Planetarium’s collection by Dr. Alan Guth

    These tiny density variations were indeed measured in the CMB in the early 1990s — the feat that earned John Mather, the Webb telescope’s top scientist, his Nobel. But even before they were measured, people like Faber were working the dense spots into the plot. In 1984, she and three co-authors published a paper in Nature that strung everything together. “It’s the first soup-to-nuts description of how inflation can make fluctuations and what the fluctuations would do later to make galaxies,” she said.
    But the story was speculative from start to finish. And even if it was broadly true, key dates and details were unknown.

    One of the Hubble telescope’s most impactful discoveries, and a major impetus for building its successor, the Webb, occurred in 1995, two years after its corrective lens was installed. Bob Williams, then the director of the Space Telescope Science Institute in Baltimore, the operations center for Hubble as it will be for Webb, decided at the suggestion of some postdocs to devote all 100 hours of his “director’s discretionary time,” with which he could point Hubble wherever he wanted, to pointing it at nothing — a dark, featureless little patch of sky narrower than a thumbnail moon. The idea was to look for any incredibly faint, distant objects that might have been hiding beyond the reach of less sensitive telescopes.

    Colleagues thought this was a waste. The late John Bahcall tried to talk Williams out of it. Bahcall and his wife, Neta Bahcall, well-known astrophysicists, were typical in thinking that structures like stars and galaxies arose relatively late in cosmic history. If so, then trying to resolve faint, faraway, long-ago objects wouldn’t work, because none would exist. The Bahcalls and many other theorists thought Williams’ photo would come out dark.

    But during the 100-hour exposure, the lid of a treasure chest opened: The small rectangle of space glittered with thousands of galaxies of all shapes, sizes and hues. Astronomers were stunned.



    Taken over 10 days in December 1995, the Hubble Deep Field photo revealed about 3,000 galaxies within a patch of sky about one-twelfth the width of the moon.

    Robert Williams and the Hubble Deep Field Team (STScI) and NASA/ESA

    Farther-away galaxies in the Hubble Deep Field photo appear redder, since their light has traveled longer through expanding space to get here and therefore has been stretched, or “redshifted,” to longer wavelengths. Through this color-coding, the Deep Field image provides a 3D view of the cosmos and a timeline of galaxy evolution. Galaxies appear at all ages and stages of development — proof that the universe has changed radically over time. “Gone out of the window, never to be heard from again, was the steady-state theory,” said Faber. “That was a great intellectual breakthrough, that you could take one picture with a telescope, you could look back in time, and you could see that the universe was a different beast back then.”

    The photo showed that bright objects formed in the universe far more quickly than most experts expected. This bolstered the theory that they didn’t form on the strength of their gravity alone, but were carried on the backs of merging dark matter halos.
    Galaxies in early times were strange-looking — small and disheveled, like ugly ducklings that would take billions of years to grow into swans. “The beautiful universe with the beautiful [spiral and elliptical galaxies] of today is really kind of a late development,” Faber said, “and that too was visible in the picture.” Some of the duckling galaxies were colliding and merging, supporting the hierarchical clustering theory of cosmic structure growth. And clumps of stars in the long-ago galaxies were surprisingly bright, indicating that the stars were far more massive and luminous than modern, sun-type stars.

    Astronomers observed that most galaxies reached peak luminosity, forming stars most quickly, around “redshift 2” — the distance from which light has stretched to twice its emitted wavelength by the time it gets here, corresponding to about 2 billion years after the Big Bang. After that, for reasons now thought to relate to the mysterious supermassive black holes growing at galaxies’ centers, many galaxies dimmed.
    The most striking thing about the timeline of galaxy evolution visible in the Deep Field photo, though, was that there’s no beginning in sight. As far as Hubble’s glass eye could see, there were galaxies. In even deeper-field photos taken with upgraded cameras that astronauts installed on the telescope later, smudges of light have been tentatively spotted as far off as redshift 10, which corresponds to around 500 million years after the Big Bang. It’s now thought likely that structures started forming hundreds of millions of years before that.

    But galaxies in the process of forming, their matter somehow fragmenting into stars for the first time, are both too far and too faint for Hubble to detect, and too redshifted: The light from these galaxies has stretched straight out of the visible part of the electromagnetic spectrum and into the infrared. To see them, we need a bigger, infrared-sensing telescope.

    “What Hubble succeeded in doing with the Hubble Deep Field is finding that there were galaxies at redshifts much higher than we thought,” Neta Bahcall told me. “A question for James Webb is when did it start, and how did it start so early.”
    • Planets Out the Wazoo
    In October 1995, two months before Hubble stared at nothing and glimpsed the history of time, the Swiss astronomer Michel Mayor announced another major discovery at a conference in Florence, Italy: He and his graduate student, Didier Queloz, had spotted a planet orbiting another star.

    In the back of the auditorium at Mayor’s talk, Natalie Batalha, then a graduate student from California, failed to register the importance of what she had just heard. “It’s funny how these things happen, because in retrospect it was a pivotal moment,” Batalha said recently, framed by three planets orbiting a star in her virtual background. “It was the dawn of this new era of exoplanet exploration, but was also a transformational moment in my life, and I didn’t know it yet.”



    Didier Queloz (left) and Michel Mayor in 1995, shortly after the publication of the Nature paper announcing the discovery of the exoplanet 51 Pegasi b.

    Courtesy of Didier Queloz

    At the time, exoplanet searching was a scientific backwater, and Mayor and Queloz’s method had seemed like a long shot. Using a spectrograph, which splits starlight into its color components, they monitored more than 100 sunlike stars hoping to detect a Doppler shift, where an object looks bluer or redder when it’s approaching or receding, respectively. This could indicate that the star is wobbling because it is disturbed by the gravity of an orbiting planet. The technique seemed far-fetched because a planet would have to be ludicrously heavy and close to its host star to set the star wobbling enough to be seen with the best available spectrographs. Yet when Mayor and Queloz looked at 51 Pegasi, a sunlike star 50 light-years away, the wobble was huge: Eliminating other possibilities, they determined that a Jupiter-size planet whips around the star once every 4.2 days, eight times closer in than Mercury’s distance from our sun.

    Not only had Mayor and Queloz bagged an exoplanet (and, eventually, the other half of the 2019 Nobel Prize in Physics, shared with Peebles), the planet itself, 51 Pegasi b, single-handedly upended the textbook understanding of what solar systems are like. As the planetary scientist Heidi Hammel put it, “We had been taught a lovely fairy tale about how our solar system formed,” one designed to explain why rocky planets lie close to a star while giant gas and ice planets form far away. So what was 51 Pegasi b, a “hot Jupiter,” doing practically grazing its sun?

    Batalha remembers the audience’s reaction in Florence to Mayor’s presentation — silence. Soon enough, though, skepticism gave way to more hot-Jupiter discoveries. And as telescopes and techniques improved, other exoplanets showed up as well. Sixteen years after that day in Florence, Batalha would lead the NASA team that discovered the first confirmed rocky exoplanet, Kepler 10b.
    • Much much more info here (article continues ...).
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    Default Re: The Power Of The James Webb Telescope in Space To Be Launched in 2021

    Thanks, John. I really enjoyed reading this...

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    Default Re: The Power Of The James Webb Telescope in Space To Be Launched in 2021

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    Exclamation Re: The Power Of The James Webb Telescope in Space To Be Launched in 2021

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    Thumbs up Re: The Power Of The James Webb Telescope in Space To Be Launched in 2021

    • What's Different About the James Webb Telescope?

    very well done video!

    cheers,
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    Default Re: The Power Of The James Webb Telescope in Space To Be Launched in 2021

    • We Might Discover Humanoid Aliens on Teegarden-b

    Here's how we might find human aliens on the exoplanet Teegarden b... Teegarden b is the most earth-like planet ever found. It is 95% similar to earth, based on the Habitable Exoplanets Catalogue. But could humans already be living there? At 12.5 light years away, with current technology it would take 19,500 years to reach Teegarden b! But what if when we reach the planet, we find humans are already there?
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    • James Webb Telescopes Terrifying Discovery Awaiting NASA:
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    Default Re: The Power Of The James Webb Telescope in Space To Be Launched in 2021

    • The James Webb Space Telescope L-30 Briefings: Science Goals:

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    Lightbulb Re: The Power Of The James Webb Telescope in Space To Be Launched in 2021

    • The $11-Billion Webb Telescope Aims to Probe the Early Universe & Exoplanets!
    Three decades after it was conceived, Hubble’s successor is set for launch. Here’s why astronomers around the world can’t wait.

    • The 6.5-metre-wide primary mirror of the James Webb Space Telescope is folded up for launch. Credit: NASA/Chris Gunn
    Lisa Dang wasn’t even born when astronomers started planning the most ambitious and complex space observatory ever built. Now, three decades later, NASA’s James Webb Space Telescope (JWST) is finally about to launch, and Dang has scored some of its first observing time — in a research area that didn’t even exist when it was being designed.

    Dang, an astrophysicist and graduate student at McGill University in Montreal, Canada, will be using the telescope, known as Webb for short, to stare at a planet beyond the Solar System. Called K2-141b, it is a world so hot that its surface is partly molten rock. She is one of dozens of astronomers who learnt in March that they had won observing time on the telescope. The long-awaited Webb — a partnership involving NASA, the European Space Agency (ESA) and the Canadian Space Agency (CSA) — is slated to lift off from a launch pad in Kourou, French Guiana, no earlier than 22 December.

    If everything goes to plan, Webb will remake astronomy by peering at cosmic phenomena such as the most distant galaxies ever seen, the atmospheres of far-off planets and the hearts of star-forming regions swaddled in dust. Roughly 100 times more powerful than its predecessor, the Hubble Space Telescope, which has transformed our understanding of the cosmos over the past 31 years, Webb will reveal previously hidden aspects of the Universe.

    • The Webb telescope will spend hundreds of hours surveying this patch of sky, seen here in an image from the Hubble Space Telescope that captures 7,500 galaxies, some more than 13 billion years old.Credit: NASA, ESA, Rogier Windhorst (ASU), S. Cohen (ASU), M. Mechtley (ASU), M. Rutkowski (ASU), Robert O'Connell (UVA), P. McCarthy (OCIW), N. Hathi (UC Riverside), R. Ryan (UC Davis), Haojing Yan (OSU), Anton M. Koekemoer (STScI)
    “Webb has such transformative capabilities that — to me — it’s going to be the ‘before’ times and the ‘after’ times,” says Jane Rigby, an astrophysicist at NASA’s Goddard Space Flight Center in Greenbelt, Maryland, who serves as Webb’s operations project scientist.

    But if anything goes wrong, it will be an ignominious setback to what is already the most expensive astronomical gamble in history. The telescope took decades and more than US$10 billion to develop, and frequent delays repeatedly ate into NASA’s astrophysics budget. Just this year, the telescope has been enveloped in controversy over whether it ought to remain named after James Webb, who headed NASA in the 1960s when a NASA employee was fired on suspicion of being gay. Webb also held a high-ranking position in the US Department of State in the late 1940s and early 1950s, at a time when that department was systematically rooting out and firing gay and lesbian people because of their sexual orientation.

    When the telescope lifts off after so many delays and so much debate, it will carry with it the hopes of thousands of astronomers around the world. “There aren’t many times in your life when you’re on the cusp of such a big thing,” says Heidi Hammel, an astronomer and vice-president for science at the Association of Universities for Research in Astronomy in Washington DC, who has worked on Webb for decades. “There are a lot of emotions.”
    • Decades of development
    The first glimmers of what would become Webb arose at a workshop at the Space Telescope Science Institute in Baltimore, Maryland, in 1989. It was the year before the launch of the Hubble Space Telescope, and scientists were already thinking about how to follow up that transformative observatory. What ultimately emerged were plans for a space telescope with a 6.5-metre-wide primary mirror, nearly three times the size of Hubble’s, and made up of 18 hexagonal segments. The mirror is so large that it must be folded up like origami during launch and unfurled once in space. Shading it will be a kite-shaped sunshield the size of a tennis court, made of five aluminium-coated layers that block the Sun’s heat and keep the telescope cool enough to operate.

    Webb’s overall cost was originally estimated at $1 billion — an appraisal few believed even then — and has since ballooned. NASA provided US$9.7 billion, including funds to cover operating costs in space; €700 million (US$810 million) came from ESA; and the CSA contributed Can$200 million (US$160 million). The project’s skyrocketing costs drew intense scrutiny from government auditors as well as perennial questions as to whether it would be worth its unprecedented price tag. “To be truly transformational in a field, you have to build the tool you need,” says Hammel. “This is what it costs to do this.”

    Plagued by repeated cancellations and design changes, the telescope finally took shape in laboratories around the world and was then assembled at Goddard. It was later combined with the rest of the observatory at Northrop Grumman Aerospace Systems in Redondo Beach, California. There, Webb ran into even more trouble when technicians damaged it by using the wrong solvent to clean propulsion valves. Later, screws literally came loose during testing.

    Now, 32 years after its conception, Webb is finally sitting at the spaceport in Kourou in preparation for launch. It is destined for a point in space 1.5 million kilometres from Earth — too far away for astronauts to visit and fix the telescope if something goes wrong. Hubble required an after-launch repair in 1993, when astronauts used the space shuttle to get to the Earth-orbiting observatory and install corrective optics for its primary mirror, which had been improperly ground.

    If it launches successfully, Webb will probe the cosmos in the near- to mid-infrared wavelengths, most of which are longer than Hubble can see. That means Webb can study light that has travelled from faraway galaxies and been stretched to redder wavelengths by the expansion of the Universe. Webb will also be able to study dust that enshrouds star-forming regions as well as the gas between the stars, both of which are not as visible at shorter wavelengths. Like Hubble, it will be able to take spectra of astronomical objects, meaning it can split their light into components to determine what they are made of.

    Earth’s atmosphere interferes with most ground-based infrared astronomical studies. Space-based telescopes, such as ESA’s Herschel Space Observatory, which operated between 2009 and 2013, have explored the Universe in infrared light before. But Webb’s enormous mirror and suite of sensitive instruments (see ‘New eye in the sky’) mean that its discoveries will surpass those of any previous infrared space telescope, scientists say. “It’s going to change a lot of what we know about a lot of areas of astronomy,” says Jeyhan Kartaltepe, an astronomer at the Rochester Institute of Technology in New York.

    • Graphic: Nik Spencer/Nature; ‘Cold telescope’ main image: NASA GSFC/CIL/Adriana Manrique Gutierrez
    Because it can spot faint red objects, Webb is primed to observe some of the first stars and galaxies to form after the Big Bang created the Universe 13.8 billion years ago. Webb will almost certainly shatter the record for the most distant galaxy ever observed, which is currently held by an unassuming galaxy named GN-z11 that lies 13.4 billion light years from Earth1,2.

    One large study will look at a region of sky that is the size of three full Moons, aiming to capture half a million galaxies in it. This survey, known as COSMOS-Webb, builds on an ongoing project that has used nearly every major ground- and space-based telescope to study the same patch of sky, which lies along the celestial equator and can be seen from both the Northern and Southern hemispheres. Webb will look at this field for more than 200 hours, making it the biggest project for the observatory’s first year of science and creating a rich data set for astronomers to mine for discoveries. Webb’s infrared view will probe, for instance, the period from around 400,000 years to 1 billion years after the Big Bang, when the first stars and galaxies lit up the Universe. This epoch, known as the cosmic reionization era, set the stage for today’s galaxies to evolve. “There’s a lot we don’t know about that time period,” says Kartaltepe, who co-leads COSMOS-Webb.

    By observing these extremely distant astronomical objects, scientists can answer questions such as how the first stars assembled into galaxies and how those galaxies evolved over time. Getting a better picture of galaxy formation in the early Universe will help astronomers to understand how the modern cosmos came to be.
 Mariska Kriek, an astronomer at Leiden Observatory in the Netherlands, plans to use Webb to study distant galaxies that are no longer forming stars. The observations will reveal the chemical composition of stars in those galaxies and the velocities at which they are moving. Those data, in turn, will help Kriek to unravel the mystery of how and why these galaxies stopped forming stars at some point in their history, unlike galaxies that did not stop3. “We’re looking for a very, very faint signal,” she says. “This is really what James Webb is going to open up.”


    Graphic: Nik Spencer/Nature
    • Peering at distant planets
    When not looking at stars and galaxies, Webb will spend a lot of its time scrutinizing planets, particularly some of the thousands that have been discovered beyond the Solar System. It can watch as a planet slips across the face of a star and the star’s light briefly shines through the planet’s atmosphere. Webb’s spectral analysis can reveal the composition of planetary atmospheres in greater detail than ever before — and astronomers are particularly keen to find molecules such as methane and water, which signal conditions that could support life. In its first year, Webb will study some of the most famous exoplanets, including the seven Earth-sized worlds that orbit the star TRAPPIST-1.

    Dang will observe several exoplanets using Webb, but the project she is leading will explore the world K2-141b, which is just 1.5 times the size of Earth and travels so close to its star that part of it is molten. It is an example of a rare ‘lava planet’ with a geology unlike anything known in the Solar System. Webb’s infrared vision might detect minerals in K2-141b’s atmosphere that have been vaporized off its surface, and the observatory might even map temperatures across the planet. “Webb is opening a lot of avenues for exoplanet science that didn’t exist before,” says Dang.

    The repeated delays in developing and building Webb actually worked to the benefit of exoplanet scientists, says Néstor Espinoza, an astronomer at the Space Telescope Science Institute. At one point, Webb was scheduled to launch in 2011, but astronomers didn’t confirm the first atmosphere around an exoplanet until 20054,5. Webb’s delays gave them more time to tweak its instruments to suit the study of exoplanet atmospheres. “We are much better poised now than if JWST were launched in 2011,” says Espinoza.


    Graphic: Nik Spencer/Nature

    Webb will target a wide range of exoplanets, including gas giants and the class of planets that are larger than Earth but smaller than Neptune, which are the most common type of exoplanet discovered so far.

    Closer to home, Webb will have plenty of objects to look at. Astronomers hope to use its wide range of wavelengths to reveal previously unseen details of the Solar System’s residents. The colour and surface chemistry of the icy worlds in orbits near Pluto and beyond, for example, could help to reveal secrets of the Solar System’s origins. Hammel and others plan to use the telescope to study the upper atmospheres of the ice giants Neptune and Uranus, the chemical make-ups of which are best seen in the infrared. By linking studies of the upper atmosphere with those of the lower atmosphere, seen at other wavelengths by other telescopes, scientists can obtain a 3D picture of how a planet’s atmosphere behaves. This, in turn, can illuminate the workings of similar giant planets beyond the Solar System.
    • Final hurdles
    Although some scientists see benefits in the delays, many more have criticized NASA and its contractors over the years for the numerous problems in developing Webb. The telescope was strongly endorsed in a 2001 report setting out a road map for US astronomy, but NASA struggled, particularly between 2002 and 2008, to develop the many technologies required for such a complex observatory, such as the sunshield. A scathing report from an independent review in 2010 noted that key problems stemmed from NASA underestimating the time and money required: “This resulted in a project that was simply not executable within the budgeted resources,” it concluded.

    NASA restructured the management of the project in response, but in 2018, another independent review again slammed the agency for insufficient oversight. Costs were forecast to rise by another $800 million, and the launch was delayed by nearly a year — and was then further held up because of problems at Northrop Grumman and challenges stemming from the COVID-19 pandemic. Earlier this year, the controversy over the telescope’s naming broke out; NASA announced in October that it had no plans to change the name, following a historical investigation into James Webb’s actions. Many astronomers, however, have expressed unhappiness with the limited information that NASA has released about the scope of that investigation.

    Then, less than a month before a scheduled launch date of 18 December, Webb hit yet another hurdle. At the facility in Kourou, a band that clamped the telescope to the launch vehicle released unexpectedly, causing vibrations. NASA investigated and concluded that the vibration did not cause any damage.

    Graphic: Nik Spencer/Nature; Infrared simulations: Madeline Marshall (Univ. Melbourne)

    If and when Webb finally lifts off, which is always a risky procedure, the telescope faces a carefully choreographed six-month sequence of events that starts with unfolding and deploying the sunshield, then unfolding and deploying the primary and secondary mirrors. The telescope will begin cooling down as it travels towards its final orbit around the gravitationally stable point in space known as L2, or the second Lagrange point. At this location, Webb will always be pointed away from the Sun with Earth at its back, allowing it to see distant objects while the sunshield keeps it cool.

    Then come two months of synchronizing and aligning the mirrors and telescope optics, and a month of calibrating the instruments. By June 2022, if all goes well, Webb will finally be ready for science.

    Astronomers have planned the next steps carefully. “We have to hit the ground running and work very quickly,” says Kartaltepe. First will come a set of ‘early release’ observations. Their contents are closely guarded but will probably involve a series of jaw-dropping images chosen to show off the telescope’s capabilities. After that will come a series of general observations, the data from which NASA will release immediately to the astronomical community. One such project will look at infrared galaxies that formed as a result of violent galactic collisions. “We are the first guinea pigs to see what data will come off JWST and how we will analyse that data,” says Vivian U, an astronomer at the University of California, Irvine, who works on the project. “I know I’m standing on the shoulders of giants.”

    Astronomers who spent years working to build Webb’s instruments have been guaranteed observing time, as have six scientists, including Hammel, who are tasked with pursuing research of interdisciplinary interest. After that come the proposals led by principal investigators. Astronomers in Europe will get at least 15%of the observing time, and ones in Canada will have at least 5%, for their space agencies’ contributions to Webb. Proposals are assessed using dual-anonymous peer review, in which reviewers and proposers do not know each other’s names — a practice that has been shown to reduce gender bias in allocating telescope time 6.

    Webb is expected to operate for at least five years and perhaps up to ten, a lifetime dictated by the amount of fuel that it uses to orient itself in space. In the meantime, the ageing Hubble continues to limp along. It was last upgraded by astronauts in 2009, and has been slowly degrading since then. A computer failure knocked it offline in June, and engineers had to switch to a back-up system before getting it working again in July. Hubble’s science instruments also went offline in October owing to internal communications problems. Engineers restored all of the instruments to operation in early December.

    After many years of waiting, astronomers are more than ready for Webb to pick up the baton of discovery from Hubble. “I’m probably most excited for the things we don’t know yet,” says Kriek.

    Nature 600, 208-212 (2021)
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    Default Re: The Power Of The James Webb Telescope in Space To Be Launched in 2021

    • James Webb Space Telescope: A Giant Leap towards 'Other Earths'?


    One of the James Webb telescope's missions is to look for conditions that could sustain life outside our solar system.
    There is only one Earth... that we know of.

    But outside our own solar system, other stars give warmth and light to planets and, possibly, life.

    Soon to offer a better look at these so-called exoplanets is NASA's new James Webb telescope, which is set to launch this month and become the largest and most powerful observatory in orbit.

    One of its major missions is to look for conditions that could sustain life outside our solar system, where scientists have only recently been able to look for it.
    The first exoplanet observed—51 Pegasi b—was discovered in 1995 and since then nearly 5,000 others have been noted, from gas giants similar to our solar system's Jupiter or Neptune to rocky planets like Earth.

    Some are a habitable distance from their suns, in a range fancifully named the Goldilocks Zone.

    But beyond being neither too close to, nor too far from the stars they orbit, little is known about these planets or what they are made of.

    They are too far away to be observed directly and rocky planets, which are more susceptible to be capable of sustaining life as we know it, tend to be even smaller and harder to observe.

    So far, astronomers have detected them as they pass in front of the stars they orbit, capturing tiny variations in luminosity.

    This has allowed them to determine their size and density but the rest—their atmospheric composition, what's going on on their surfaces—is left to discover.



    The Mid-Infrared Instrument will use a camera and a spectrograph to see mid-infrared light invisible to the human eye.
    • 'Look at their innards'
    Astrophysicists hope the Webb telescope will help fill in some of these gaps.

    Equipped with a new piece of technology called the Mid-Infrared Instrument (MIRI), it will use a camera and a spectrograph to see light in the mid-infrared region of the electromagnetic spectrum, invisible to the human eye.

    "It will revolutionise how we see planets' atmospheres. We're going to get a look at their innards!" said Pierre-Oliver Lagage of the French space agency who worked on MIRI with a US and European team.

    Pierre Ferruit, a Webb project scientist at the European Space Agency, explained that MIRI will be able to read the infrared signature of light filtered through various substances in planets atmospheres as they pass in front of their stars.

    In this way, Ferruit told AFP, scientists should be able to tell whether they contain molecules like water vapour, carbon monoxide and methane.
    Those three substances are present in Earth's atmosphere and could potentially signal biological activity on a planet's surface.

    "To think that twenty years ago we knew of almost no exoplanets and now we are about to find out what their atmospheres are made of—it's huge," Ferruit said.
    • Trappist-1
    Rene Doyon is head of the Institute for Research on Exoplanets in Montreal and main scientist on another of the Webb's instruments, the Near Infrared Imager and Slitless Spectrograph.

    Scientists should be able to tell whether exoplanets' atmospheres contain molecules like water vapor, carbon monoxide and methane.

    "My dream would be to find an atmosphere around a rocky planet in a habitable zone with water molecules," Doyon told AFP, describing three conditions that would make life as we know it on Earth possible. But there are pitfalls: on Venus for example scientists recently thought they found phosphine, associated with biological activity on Earth. Subsequent research, however, showed there were no traces of the gas.

    Doyon said finding the origins of biological molecules will probably be "beyond the capabilities" of the Webb telescope. "That will be for later," confirmed Ferruit. "For now we are looking for conditions that are favourable to life, like the presence of liquid water." ... Such clues will narrow the focus of future missions that aim to discover "whether the Earth is one of a kind, or not".

    Webb is already set to probe a system around the planetary system Trappist-1, around 40 light years from Earth, which was discovered by Belgian scientists who named it after famous beer-brewing monks.

    It has seven planets, of which three are in a Goldilocks zone and orbit a dwarf star, whose not-too-bright light will make it easier to detect the composition of the atmosphere.

    Other instruments for direct observation will allow Webb to examine the atmospheres of "hot Jupiters" or "mini Neptunes", said Doyon.

    He said he expects new categories of exoplanets could be discovered along with plenty of surprises. "Surprise is what exoplanet discovery is made of," he said.
    Last edited by ExomatrixTV; 10th December 2021 at 14:19.
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    Default Re: The Power Of The James Webb Telescope in Space To Be Launched in 2021

    No need to follow anyone, only consider broadening (y)our horizon of possibilities ...

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