James Webb Space Telescope's 1st year in space has blown astronomers away

Just one year after launch, the James Webb Space Telescope is exceeding all expectations, and astronomers are thrilled. Launched on Dec. 25, 2021, the $10 billion infrared observatory was designed to learn how galaxies form and grow, to peer far back into the universe to the era of the first galaxies, to watch stars be born inside their nebulous embryos in unprecedented detail, and to probe the atmospheres of exoplanets and characterize some of the closest rocky worlds. However, the complexity of the James Webb Space Telescope (Webb or JWST), including its fold-out, segmented 21-foot (6.5 meters) mirror and its delicate sun-shield the size of a tennis court, meant that astronomers were on tenterhooks as to whether the JWST would perform as hoped. It turns out, they needn't have worried. "I guess we really weren't expecting the results to be this good," Brenda Frye, an astronomy at Steward Observatory at the University of Arizona. "It's amazing," Steve Longmore, an astrophysicist at Liverpool John Moores University in the U.K., told Space.com. "It's delivering at least as well, and better in a lot of circumstances, than what we were expecting." And if it exceeds its own targets, it definitely surpasses those of its predecessors. "It's leaps and bounds better than what we've been able to see before," Susan Mullally, JWST's deputy project scientist from the Space Telescope Science Institute (STScI) in Maryland, which operates the observatory, told Space.com, adding that she is "blown away by the imagery, honestly. The images are beautiful."

The James Webb Space Telescope launched atop an Ariane 5 rocket from French Guiana on Dec. 25, 2021. (Image credit: NASA/Bill Ingalls)

The rings of Neptune

The main reason that JWST is performing so well is because of its superlative optics, which are able to achieve their maximum potential resolution for the majority of infrared wavelengths that the telescope observes in. This success means that JWST's images have a clarity to them that were unobtainable by the likes of the Hubble Space Telescope and NASA's retired Spitzer Space Telescope, or larger telescopes on the ground such as those at the Keck Observatory in Hawaii, whose vision is blurred by Earth's atmosphere.

But with JWST, individual stars so close together they were once indistinguishable can now be resolved; the structures of very distant galaxies are now discernible; and even something close by such as the rings of Neptune pop with the most detail seen in decades.

The James Webb Space Telescope's stunning view of Neptune, with its rings clearly visible. (Image credit: NASA/ESA/CSA/STScI)

"When the JWST's images of Neptune first came out, both Heidi [Hammel, an interdisciplinary scientist on JWST and an expert on the outer planets of the solar system] and myself looked at them, and then at each other, and asked, 'are we really looking at Neptune'?" Naomi Rowe-Gurney, an astronomer at NASA Goddard Space Flight Center in Maryland, told Space.com.

Although the Keck Observatory has imaged Neptune's rings, our most impressive view before JWST came from Voyager 2's flyby in 1989. "Heidi had not seen the rings [this well] since Voyager 2, and I had never seen the rings like this because Voyager was before I was born!" Rowe-Gurney said.

Normally, faint details or features around a bright object, such as the dark and tenuous rings around blue Neptune, are difficult to see against the glare of the bright object. To counteract this, an instrument is required to have the characteristic of "high dynamic range" to take in both the faint and the bright at the same time.

"We didn't realize that JWST would have this amazing dynamic range and be able to resolve really faint things like the rings of Neptune and the small moons and rings of Jupiter," Rowe-Gurney said.

Alien atmospheres

It's not only the planets of our solar system that JWST is scrutinizing. A key aim of the telescope is to detect the composition of exoplanets' atmospheres using a technique called transmission spectroscopy. As a planet transits its star, the star's light shines through the planet's atmosphere, but atoms and molecules within that atmosphere can block some of the light at characteristic wavelengths, which gives away the composition of the atmosphere.

The first exoplanet result released from JWST was the transmission spectrum of WASP-39b, which is a "hot Jupiter" exoplanet orbiting a sun-like star located 700 light-years away. JWST detected carbon dioxide in WASP-39b's atmosphere, the first time the gas has ever been detected on an exoplanet. Other gases present included carbon monoxide, potassium, sodium, water vapor and sulfur dioxide, the last of which can only be created through photochemistry when atmospheric gases react with the ultraviolet light from the planet's star — another exoplanet first.

The James Webb Space Telescope's analysis of the atmospheric composition of WASP-39b. (Image credit: NASA/ESA/CSA/J. Olmsted (STScI))

"I keep being amazed by what we're able to do with the exoplanet data, like the carbon dioxide and the photochemistry that was found in the atmosphere of WASP-39b," Mullally said. "That was really cool, and I don't remember people talking about [detecting photochemistry] ahead of time. I'm really looking forward to seeing what we can do with the terrestrial exoplanets orbiting the cool M-dwarfs and seeing what their atmospheres are made of."

In particular, the TRAPPIST-1 planetary system of seven worlds orbiting an M-dwarf 40 light-years away is a key target of the JWST. Preliminary results, which failed to detect thick blankets of hydrogen surrounding some of the TRAPPIST-1 worlds, were released during a conference held at STScI in December, but we'll have to be patient for more comprehensive results from these planets, of which up to four could reside in their star's habitable zone.

WASP-39b was an easy first target because its star is bright and the planet's signal is strong. M-dwarfs like TRAPPIST-1 are much fainter, despite being closer.

"We have to wait until we can get enough transits of these guys to build up the signal-to-noise, because you can't do it with just one or two transits," Mullally said. "I think we're going to have to wait until at least the end of the cycle 1 observations [summer 2023] before anybody is going to be in a position to say if they've found anything really spectacular."

Star formation near and far

Another aspect of JWST's mission is to not only observe exoplanets, but to better understand how they, and their stars, form. Star formation in particular is a crucial process to understand it because it connects so many things in the universe both near and far.

Longmore is leading a study to use JWST to observe frantic star formation in a region at the center of our own Milky Way galaxy, called the central molecular zone, some 26,000 light-years from us. The center of our galaxy hosts the highest concentration of stars, and at our distance they all appear packed in — indistinguishable to the likes of the Hubble Space Telescope — while copious amounts of dust shroud most of them from view in optical light. Look with a large-aperture infrared telescope like JWST, however, and those two concerns are shoved aside.

"These are the JWST's two capabilities that are going to blow my field apart," Longmore said. The telescope's superb optics are able to resolve individual baby stars in the center of the galaxy, and infrared light will pass right through the dust to reach the observatory.

"Ordinarily, with Hubble, it's like trying to point your telescope at a brick wall and see through it," he added, "But the JWST is looking through a window in that wall and can count individual stars."

The star-forming Pillars of Creation, imaged in mid-infrared by the JWST in what will surely become an iconic picture. (Image credit: NASA/ESA/CSA/STScI/J. DePasquale (STScI)/A. Pagan (STScI))

It's taking longer to gather all the data from the center of the galaxy, but that's because it's such a complex environment, with bright, diffuse emission everywhere, and all that has to be disentangled from the relevant signal of star formation via determined and careful data processing.

"On all the projects I'm on, people are still fighting with calibration and things, but hopefully in the next six months that will change," Longmore said. He added an amusing story of how one of his team's observations had been blighted by a mysterious circle on the image. After deeper investigation, it turned out that this wasn't some mysterious new phenomenon, but that JWST had previously been looking at bright Jupiter, and the giant planet's after-image had not yet been properly flushed out of the instrument's electronic sensors!

Longmore and his colleagues are targeting the central molecular zone because it is the region in our galaxy that most resembles star-forming conditions in the early universe, when the star-formation rate was high and dense clusters of stars formed. In the Central Molecular Zone, the astronomers intend to measure a property called the initial mass function (IMF), which describes the range of stellar masses in a star-forming nebula.

Currently, astronomers do not understand what determines why stars form with the masses that they have, only that low-mass stars are much more common than luminous high-mass stars, at least in the local universe. Was this still the case over 13 billion years ago in the first galaxies? Answering that question could help explain both how galaxies formed and what ended the universe's dark ages.

Deep fields and the first galaxies

After she saw President Joe Biden reveal the first deep-field image from the JWST, of the galaxy cluster SMACS 0723, a "gravitational lens" whose massive gravity magnifies objects behind it, Frye and her student, Massimo Pascale at the University of California, Berkeley, raced to analyze the image.

"We didn't sleep for three-and-a-half days, and our paper was one of the first two papers submitted on JWST data," Frye said.

Together, they found 42 new gravitationally lensed images of 14 different high-redshift galaxies, galaxies located so far away that the expanding universe has stretched their light, making them appear redder. Further studies and more deep fields followed, and a host of high-redshift candidates were discovered by Frye's team and others, including some galaxies at record-breaking redshifts of 12, 13 and above; these redshifts mean that we see the galaxies as they existed less than 300 million years after the Big Bang.

These high-redshift galaxies have proven something of a surprise, in that they appear more luminous than models of galaxy formation predicted they should be.

"One possible explanation is that they're producing too many high-mass stars, that they have a top-heavy IMF," Longmore said, noting the importance of measuring the IMF in the central molecular zone to understand stellar masses in young neighborhoods.

Why the IMF would be different over 13.5 billion years ago is not understood, but then again the early universe seems to have been a far more intense place than it is today. "In the present day, galaxies in general are not forming stars so actively, but many galaxies formed stars more actively in the early universe," Frye said.

Frye is a member of the PEARLS (Prime Extragalactic Area for Reionization and Lensing Science) team. PEARLS is a JWST project to image a variety of deep fields, including two apparently sparse regions of sky and a number of galaxy clusters and proto-clusters, to observe the first few billion years of galaxy formation.  

The PEARLS field looking toward the North Celestial Pole. Inset are numerous types of galaxy, from interacting galaxies to ruby-red dusty star-forming galaxies. (Image credit: NASA/ESA/CSA/Rolf A. Jansen, Jake Summers, Rosalia O'Brien, Rogier Windhorst (ASU)/Aaron Robotham (UWA)/Anton M. Koekemoer (STScI)/Christopher Willmer (University of Arizona)/JWST PEARLS Team)

In December, the PEARLs team released their first dataset, of an extraordinary field of distant galaxies close to the North Ecliptic Pole. This region is directly above the main plane of the Milky Way and so is constantly visible to JWST, and it's also high above interfering features such as zodiacal dust.

Within the image are a whole host of galaxies. Some interact and some show a clear spiral structure; the collection exhibits a whole range of colors, from cobalt blue to ruby red. The latter are of great interest to Frye.

"We can now observe [in the PEARLS image] an abundance of red disk galaxies, which we think might be red spirals," Frye said. "This type of galaxy is very interesting because they are analogs of what the Milky Way might have looked like when it was younger."

The reddening is caused by huge amounts of dust in these galaxies; the dust is the result of rapid formation of massive stars that quickly die in supernova explosions and spill vast amounts of dust into space. Such galaxies are completely hidden from Hubble, but infrared light can pass through the dust and make the galaxies visible to JWST.

"The analogy is a New Year's Eve fireworks display," Frye said. "If you have a lot of fireworks going off then eventually they are obscured by dusty smoke."

The JWST has impressed scientists in the six months that it has been gathering data since becoming fully operational in June, but the real fireworks are still to come with major discoveries awaiting us.

It's slow going, requiring patience, Frye said. "There's too much for any one person to be able to study or understand on really short timescales, it's going to take us a long time to process all the data."

The results, though, will be worth it.

"It's going to completely change our understanding of our place in the universe, how the solar system formed and evolved, and how the very first stars and galaxies formed," Mullally said. "We've made great headway with this telescope, and it's going to do spectacular things."

 

James Webb Space Telescope sniffs out carbon dioxide around an alien world

The James Webb Space Telescope (JWST or Webb) has detected carbon dioxide in the atmosphere of an exoplanet in a breakthrough discovery that will usher in a new era of research on worlds outside our solar system. The detection came during the James Webb Space Telescope's first campaign focusing on exoplanets, which are planets orbiting other stars. The observations targeted a hot gas giant called WASP-39 b located some 700 light-years away from Earth in the constellation Virgo. The planet, about as massive as Saturn but larger than Jupiter in size, had previously been observed by the Hubble Space Telescope in optical wavelengths and the now-retired Spitzer Space Telescope, which like Webb observed heat-carrying infrared wavelengths. The previous observations revealed the presence of water vapor, sodium and potassium in the planet's atmosphere, but it wasn't until Webb that scientists caught the signature of carbon dioxide. "As soon as the data appeared on my screen, the whopping carbon dioxide feature grabbed me," Zafar Rustamkulov, a graduate student at Johns Hopkins University in Baltimore, USA and a member of the transiting exoplanet team which undertook this investigation, said in a statement (opens in new tab). "It was a special moment, crossing an important threshold in exoplanet sciences." Carbon dioxide has never been detected on any exoplanet before. But astronomers hope that the compound can help them better understand the formation history and evolution of the planets where it's found, scientists said.

"This unequivocal detection of carbon dioxide is a major milestone for exoplanet atmosphere characterisation," Laura Kreidberg, director of the Max Planck Institute for Astronomy in Germany and co-author of a paper describing the discovery, said in a statement (opens in new tab). "Carbon dioxide helps us measure the complete carbon and oxygen inventory of the atmosphere, which is highly sensitive to the conditions in the disk where the planet formed."

Such measurements can help identify how far from its star the planet formed and determine how much solid and gaseous material it accumulated as it migrated to its current location.

The discovery was made using Webb's NIRSpec instrument, a highly sensitive spectrograph that splits incoming light into barcode-like spectra that reveal how the observed objects absorb light. Neither Webb nor any other existing telescope can capture direct images of the exoplanet or its atmosphere; instead, researchers compare observations of the star's typical light to light seen through the atmosphere as the planet passes in front of it.

The measurements of WASP-39 b were gathered on July 10, two days before the first official release of Webb images.

The researchers believe the telescope will be able to detect carbon dioxide in the atmospheres of other types of planets, including Earth-like rocky bodies scattered across the galaxy.

"The exoplanet community has been searching for the signature of carbon dioxide for decades," Kreidberg said. "With the extraordinary new capability of JWST, it will be possible to routinely detect carbon dioxide for hot Jupiters, as well as smaller, cooler planets more like our own Earth."

WASP-39 b orbits extremely close to its parent star, WASP-39, at less than 1/20th the distance between Earth and the sun), completing one orbit about every four Earth days. The planet was discovered in 2011 and can only be observed through the transits it makes around WASP-39, which cause brief dips in the star's brightness.

A paper describing the research has been accepted for publication by Nature; a preprint of the paper is available on arXiv.org(opens in new tab).

NASA releases first color image from James Webb Space Telescope

A deep field of distant galaxies, some dating back to the first billion years after the Big Bang, is the first full-color image to come from the James Webb Space Telescope. The image, released at a White House event July 11 and called “Webb’s First Deep Field,” is a sneak preview of a broader set of early release observations that NASA and its European and Canadian partners on JWST plan to publish July 12. The White House event, attended by President Joe Biden and Vice President Kamala Harris, was announced with less than 24 hours’ notice. The image shows a galaxy cluster called SMACS 0723 about 4.5 billion light-years away. The cluster acts as a gravitational lens, bringing into view far more distant galaxies, some of which appear in the image as arcs. “We’re looking back more than 13 billion years,” said NASA Administrator Bill Nelson at the event. The NASA statement accompanying the image release didn’t give specifics on the more distant galaxies visible in the image, which involved 12.5 hours of images taken at several wavelengths. The Big Bang took place an estimated 13.8 billion years ago, meaning those distant galaxies date back to when the universe was less than a billion years old. The detail in the image comes from a very tiny part of the sky. “If you held a grain of sand on the tip of your finger at arm’s length, that is the part of the universe you’re seeing. Just one little speck of the universe,” Nelson said.

Biden appeared pleased by what he saw and by the performance of JWST. “It symbolizes the relentless spirit of American ingenuity and it shows what we can achieve, what more we can discover,” he said of the space telescope, which finally launched last December after billions of dollars of cost overruns and years of schedule delays. JWST is now working better than expected at the Earth-sun L-2 point 1.5 million kilometers away. “These images are going to remind the world that America can do big things.”

“This telescope is one of humanity’s great engineering achievements,” added Harris. Both she and Biden emphasized the role of international cooperation in JWST’s development, including how, according to Harris, “a scientific endeavor can build upon the international rules and norms that govern our cooperation in space.”

The White House event started more than an hour later because, Biden said, he was busy preparing for an upcoming trip to the Middle East. Media were ushered out of the room and the webcast ended after only about 10 minutes.

Scientists and others were immediately impressed, though, with the image. “This is just a first glimpse of what Webb can do,” said Macarena Garcia Marin, ESA instrument scientist for a mid-infrared instrument on JWST called MIRI, in an ESA statement. “While we are truly in awe today of Webb’s first deep field, I can’t help but think of what images and science results are just around the corner in the many years to come.”

“The first image from the James Webb Space Telescope unveiled this evening is an incredible preview of its remarkable technology and scientific power,” said Rep. Eddie Bernice Johnson (D-Texas), chair of the House Science Committee, in a statement that featured bipartisan praise of the spacecraft from the committee’s leadership. “As a steadfast supporter of Webb and its mission, I am elated to see this image today — an image that has been 20 years of hard work in the making.”

The deep field image was originally scheduled to be released July 12 with the other early release observations. NASA and its partners will still release those other observations at that event. The other observations, announced by NASA July 8, include the Carina Nebula and Southern Ring Nebula within our own galaxy and the galaxy group Stephan’s Quintet about 290 million light-years away. NASA will also release spectra of the exoplanet WASP-96b, a “hot Jupiter” planet orbiting close to its star.

JADES will go deeper than the Hubble Deep Fields

Astronomers announced this month that a new deep-field survey called JADES will be carried out with the James Webb Space Telescope, Hubble’s much-anticipated successor. The Webb is due to launch later this year. Astronomers announced a new deeper-than-ever sky survey this month (January 15, 2021), to be conducted with the James Webb Space Telescope, the Hubble telescope’s successor, scheduled for launch in October of this year. The new survey is abbreviated JADES, which is short for James Webb Space Telescope Advanced Deep Extragalactic Survey. The survey will be like the Hubble Deep Fields, but deeper still. Its main goal is to see far away in space – and thus far back into the very young universe – and image it just at the end of the so-called Cosmic Dark Ages, that is, at the time when gas in the universe went from being opaque to transparent. This is also the time when the very first stars were forming – very large, massive and bright stars – in a veritable firestorm of star birth when the young universe was less than 5% of its current age. The Webb telescope will be located near the second Lagrange point – a relatively stable region of space, gravitationally speaking, known as L2 – some 930,000 miles (1.5 million km) from Earth. To conduct the new survey, the Webb telescope will be staring at a small point of space for nearly 800 hours (approximately 33 days) to be able to see fainter objects than those ever seen before and thus to find the first generation of galaxies. Astronomers want to know, among other things, how fast did these galaxies form, and how fast did their stars form? They also want to look for the very first supermassive black holes, which are thought to lie at the hearts of nearly all large galaxies, including our Milky Way.

The Hubble Ultra Deep Field (in its eXtreme version) is the deepest view of the universe yet obtained … and will be, until JADES takes over. It stretches approximately 13 billion light-years and includes approximately 10,000 galaxies. It took 11.3 days for the Hubble Space Telescope to collect these ancient photons. Try downloading the largest version and zoom in on different sections. We’re seeing these galaxies as they were billions of years ago. How might they look today? Image via NASA/ ESA/ S. Beckwith (STSci)/ HUDF team.

The long-anticipated launch of the James Webb Space Telescope has been postponed a number of times for a variety of reasons, most recently because of effects of the Covid-19 pandemic. It is the formal successor to the Hubble Space Telescope, but is equipped with instrumentation able to image further into the infrared part of the electromagnetic spectrum than Hubble could.

This capability also makes it a worthy successor to the infrared Spitzer Space Telescope which recently went into retirement.

What makes the infrared part of the spectrum so important for surveys like JADES? If you look really deep, you will also look back in time, and the farther back in time you look, the more redshifted the galaxies are (the farther away they are, the faster they move away from us, and the more their light has been shifted towards the red part of the spectrum). This means that the light we want to observe, originally in the optical (visible) part of the electromagnetic spectrum, might not even show much in the optical part anymore. Instead, it’s been shifted to longer wavelengths, into the infrared regime.

In other words, the use of infrared cameras is necessary to be able to see the light from the first generation of galaxies. Daniel Eisenstein, a professor of astronomy at Harvard University, said:

Galaxies, we think, begin building up in the first billion years after the Big Bang, and sort of reach adolescence at 1 to 2 billion years. We’re trying to investigate those early periods. We must do this with an infrared-optimized telescope because the expansion of the universe causes light to increase in wavelength as it traverses the vast distance to reach us. So even though the stars are emitting light primarily in optical and ultraviolet wavelengths, that light is shifted quite relentlessly out into the infrared. Only Webb can get to the depth and sensitivity that’s needed to study these early galaxies.

In fact, the James Webb Space Telescope was built specifically for this purpose. Up to now, infrared images are much less resolved – less clear – than optical images, because of their longer wavelength. With its much larger collecting area, the Webb will be able to image, in infrared, at the same resolution – detail – that Hubble could obtain in the optical part of the spectrum.

Get ready for a whole new set of mind-blowing images of the universe, this time in the infrared, from Webb!

After having successfully deployed its solar panels – precisely as it’s supposed to do once it’s in space – the Webb telescope is shown here ready for the final tests on December 17, 2020, at NASA’s Goddard Space Flight Center. Then it will be packed up and transported to French Guyana, to be launched on October 31, 2021, via an Ariane V rocket. Image via NASA/ Chris Gunn.

The use of deep field surveys is a young science, for two reasons. First, astronomers didn’t have the right instrumentation before Hubble to do them. Second, it’s also because no one initially knew the result of staring into a piece of empty space for a long time. Such a long stare into the unknown would require valuable observation time, and if this long observation didn’t produce any results, it would be considered a waste.

But in 1995, Robert Williams, then the director of the Space Telescope Science Institute (STSci), which administrates the Hubble telescope, decided to use his “director’s discretionary time” to point the Hubble toward a very small and absolutely empty-looking part of the sky in the direction of the constellation Ursa Major the Great Bear. There were no stars visible from our Milky Way (or extremely few), no nearby galaxies visible in the field, and no visible gas clouds. Hubble collected photons for 10 consecutive days, and the result, the Hubble Deep Field, was a success and a paradigm changer: A patch of sky about as small as the eye of George Washington on an American quarter (25-cent coin) held out at arm’s length, showed a 10 billion-light-years-long tunnel back in time with a plethora of galaxies – around 3,000 of them – at different evolutionary stages along the way. The field of observational cosmology was born.

This was done again in 1998 with the Hubble telescope pointed to the southern sky (Hubble Deep Field South), and the result was the same. Thus we learned that the universe is uniform over large scales.

Next was the installation of a new, powerful camera on Hubble (the Advanced Camera for Surveys) in 2002. The incredible Hubble Ultra Deep Field was acquired in 2004, in a similarly small patch of sky near the constellation Orion, about 1/10 of a full moon diameter (2.4 x 3.4 arc minutes, in contrast to the original Hubble Deep Fields north and south, which were 2.6 x 2.6 arc minutes). And so our reach was extended even deeper into space, and even further back in time, showing light from 10 thousand galaxies along a 13-billion-light-years-long tunnel of space. If you’ll remember that the universe is about 13.77 billion years old, you’ll see this is getting us really close to the beginning!

The Hubble Ultra Deep Field was the most sensitive astronomical image ever made at wavelengths of visible (optical) light until 2012, when an even more refined version was released, called the Hubble eXtreme Deep Field, which reached even farther: 13.2 billion years back in time.

The JADES survey will be observed in two batches, one on the northern sky and one on the southern in two famous fields called GOODS North and South (abbreviated from Great Observatories Origins Deep Survey).

Marcia Rieke, a professor of astronomy at the University of Arizona who co-leads the JADES Team with Pierre Ferruit of the European Space Agency (ESA), explained:

We chose these fields because they have such a great wealth of supporting information. They’ve been studied at many other wavelengths, so they were the logical ones to do.

Look closely. Every single speck of light in this image is a distant galaxy (except for the very few ones with spikes which are foreground stars). This telescopic field of view is part of the GOODS South field. It’s one of the directions in space that’ll be observed in JADES, a new survey that aims to study the very first galaxies to appear in the infancy of the universe. Image via NASA/ Hubble Space Telescope/ James Webb Space Telescope site.

The GOODS fields have been observed with several of the most famous telescopes, covering a great wavelength range from infrared through optical to X-ray. They are not fully as deep (the observations don’t reach as far back) as the Ultra Deep Field, but cover a larger area of the sky (4-5 times larger) and are the most data-rich areas of the sky in terms of depth combined with wavelength coverage. By the way, the first deep field, HDF-N, is located in the GOODS north image, and the Ultra deep field/eXtreme (don’t you love these names?) is located in the GOODS south field.

There are a large number of ambitious science goals for the JADES program pertaining to the composition of the first galaxies, including the first generation of supermassive black holes. How these came about at such an early time is a mystery. As well, the transition of gas from neutral and opaque to transparent and ionized, something astronomers call the epoch of reionization, is not well understood. JADES team member Andrew Bunker, professor of astrophysics at the University of Oxford in the United Kingdom, who is also part of the ESA team behind the Webb telescope, said:

This transition is a fundamental phase change in the nature of the universe. We want to understand what caused it. It could be that it’s the light from very early galaxies and the first burst of star formation … It is kind of one of the Holy Grails, to find the so-called Population III stars that formed from the hydrogen and helium of the Big Bang.

People have been trying to do this for many decades and results have been inconclusive so far.

Both halves of NASA's Webb Telescope successfully communicate

For the first time, the two halves of NASA's James Webb Space Telescope - the spacecraft and the telescope--were connected together using temporary ground wiring that enabled them to "speak" to each other like they will in flight. Although it was a significant step forward for the program, this test was an optional "risk reduction" test that took advantage of an opportunity to connect the two halves of the observatory together electrically months earlier than planned. If any issues had been found, it would have given engineers more time to fix them and without causing further delays. As a bonus, it also provided a jumpstart for the separate spacecraft and telescope test teams to begin working jointly as they will when the whole observatory is put together in one piece next year. The James Webb telescope is both an exceedingly complex and rewarding undertaking for NASA and its international partners. Scientists anticipate its findings to rewrite textbooks on astronomy by providing revolutionary observations of the cosmos, while engineers and involved technicians forecast that its challenging design will enable and influence future spacecraft architecture for years to come.Each piece of Webb has undergone rigorous testing throughout various historic and state of the art facilities across the United States. This ensures the entire observatory is prepared to survive the inherent harshness of a rocket launch to space, and years of continuous exposure to the extremes encountered on a mission nearly a million miles away from Earth.

In February, Webb made an important, and symbolic step forward in its path to completion when all primary flight components of the observatory came to reside under the same roof at Northrop Grumman in Los Angeles, California. This is where all flight hardware is undergoing final assembly and testing until cleared to launch from the Guiana Space Centre near Kourou in French Guiana.

"What we did now was make electrical connections between the flight telescope and flight spacecraft to understand all the nuances of the electrical interface. Specifically in this test, the spacecraft commanded mirror motion on the telescope, and the telescope replied back with telemetry confirming it.

Even though we have tested each half with a simulator of the other half during their parallel construction, there is nothing exactly like connecting the real thing to the real thing. While the sunshield was being reassembled to get back into its environmental testing, we took advantage of the time and did a flight-to-flight electrical dry run right now to reduce schedule risk later," said Mike Menzel, Webb's Mission System Engineer.

"The full complement of electrical and software tests will be run next year when the observatory is finally fully assembled for flight."

The James Webb Space Telescope will be a giant leap forward in our quest to understand the universe and where humans fit in the great cosmic expanse. Webb will examine every phase of cosmic history: from the first luminous glows after the big bang to the formation of galaxies, stars, and planets to the evolution of our own solar system.

Allowing for unprecedented scientific observation and discovery worldwide. Webb will broaden and enrich the discoveries achieved by the great space observatories Hubble, Spitzer, and Chandra.

"This test also afforded us an early chance to ensure that the two teams, who had been working separately over the years building and testing the two separate halves of Webb respectively, were able to operate as a single observatory test team.

"We are enthused that the early communications and commanding risk reduction test has been successfully executed. The procedure was designed and executed by an integrated set of team members from Goddard Space Flight Center, Northrop Grumman, and Ball Aerospace," said Jeff Kirk, Test Operations Lead.