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How JWST revolutionized astronomy in 2022

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Part of the dwarf galaxy Wolf–Lundmark–Melotte (WLM) captured by the James Webb Space Telescope’s Near-Infrared Camera.Credit: Science: NASA, ESA, CSA, Kristen McQuinn (RU), Image Processing: Zolt G. Levay (STScI)

The crowd in the auditorium began murmuring, then gasping, as Emma Curtis-Lake put her slides up on the screen. “Amazing!” someone blurted out.

Curtis-Lake, an astronomer at the University of Hertfordshire, UK, was showing off some of the first results on distant galaxies from NASA’s James Webb Space Telescope (JWST). It was not the last time astronomers started chattering in excitement this week as they gazed at the telescope’s initial discoveries, at a symposium held at the Space Telescope Science Institute (STScI) in Baltimore, Maryland.

In just its first few months of science operations, JWST has delivered stunning insights on heavenly bodies ranging from planets in the Solar System to stars elsewhere in the cosmos. These discoveries have sharpened researchers’ eagerness to take more advantage of the observatory’s capabilities. Scientists are now crafting new proposals for what the telescope should do in its second year, even as they scramble for funding and debate whether the telescope’s data should be fully open-access.

White-knuckle launch

JWST launched on 25 December 2021 as the most expensive, most delayed and most complicated space observatory ever built. Astronomers held their breath as the US$10-billion machine went through a complex six-month engineering deployment in deep space, during which hundreds of potential failures could have seriously damaged it.

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But it works — and spectacularly so. “I feel really lucky to be alive as a scientist to work with this amazing telescope,” says Laura Kreidberg, an astronomer at the Max Planck Institute for Astronomy in Heidelberg, Germany.

First out of the floodgate, in July, came a rush of preprints on the early evolution of galaxies. The expansion of the Universe has stretched distant galaxies’ light to infrared, the wavelengths that JWST captures. That allows the telescope to observe faraway galaxies — including several so distant that they appear as they did just 350 million to 400 million years after the Big Bang, which happened 13.8 billion years ago.

Many early galaxies spotted by JWST are brighter, more diverse and better formed than astronomers had anticipated. “It seems like the early Universe was a very profound galaxy-maker,” says Steven Finkelstein, an astronomer at the University of Texas at Austin.

Some of these initial findings are being revised as data calibrations improve, and many of the early claims about distant galaxies await confirmation by spectroscopic studies of the galaxies’ light. But astronomers including Curtis-Lake announced on 9 December that they have already nailed spectroscopic confirmation of two galaxies that are farther away than any ever previously confirmed.

’Mindblowing’ detail

In closer regions of the cosmos, JWST is yielding results on star formation and evolution, thanks to its sharp resolution and infrared vision. “Compared to what we can see with Hubble, the amount of details that you see in the Universe, it’s completely mind-blowing,” says Lamiya Mowla, an astronomer at the University of Toronto in Canada. Thanks to telescope’s keen vision, she and her colleagues were able to spot bright ‘sparkles’ around a galaxy that they dubbed the Sparkler; the sparkles turned out to be some of the oldest star clusters ever discovered. Other studies have unveiled details such as the hearts of galaxies where monster black holes lurk.

Another burst of JWST discoveries comes from studies of exoplanet atmospheres, which the telescope can scrutinize in unprecedented detail.

For instance, when scientists saw the first JWST data from the exoplanet WASP-39b, signals from a range of compounds, such as water, leapt right out. “Just looking at it was like, all the answers were in front of us,” says Mercedes López-Morales, an astronomer at the Center for Astrophysics | Harvard & Smithsonian in Cambridge, Massachusetts. Now scientists are keenly anticipating data about other planets including the seven Earth-sized worlds that orbit the star TRAPPIST-1. Early results on two of the TRAPPIST-1 planets, reported at the symposium, suggest that JWST is more than capable of finding atmospheres there, though the observations will take more time to analyse.

JWST has even made its first planet discovery: a rocky Earth-sized planet that orbits a nearby cool star, Kevin Stevenson at the Johns Hopkins University Applied Physics Laboratory in Laurel, Maryland, told the meeting.

The telescope has also proved its worth for studying objects in Earth’s celestial neighbourhood. At the symposium, astronomer Geronimo Villanueva at NASA’s Goddard Space Flight Center in Greenbelt, Maryland, showed new images of Saturn’s moon Enceladus. Scientists knew that Enceladus has a buried ocean whose water sometimes squirts out of fractures in its icy crust, but JWST revealed that the water plume envelops the entire moon and well beyond. Separately, engineers have also figured out a way to get JWST to track rapidly moving objects, such as Solar System planets, much better than expected. That led to new studies such as observations of the DART spacecraft’s deliberate crash into an asteroid in September, says Naomi Rowe-Gurney, an astronomer also at Goddard.

Yet all these discoveries are but a taste of what JWST could ultimately do to change astronomy. “It’s premature to really have a full picture of its ultimate impact,” says Klaus Pontoppidan, JWST project scientist at STScI. Researchers have just begun to recognize JWST’s powers, such as its ability to probe details in the spectra of light from astronomical objects.

Applications are now open for astronomers to pitch their ideas for observations during JWST’s second year of operations, which starts in July. The next round could result in more ambitious or creative proposals to use the telescope now that astronomers know what it is capable of, Pontoppidan says.

Amid all the good news, there are still glitches. Primary among them is a lack of funding to support scientists working on JWST data, says López-Morales. “We can do the science, we have the skills, we are developing the tools, we are going to make groundbreaking discoveries but on a very thin budget,” she says. “Which is not ideal right now.”

Available to all?

López-Morales chairs a committee that represents astronomers who use JWST, and their to-do list is long. It includes surveying scientists about whether all of the telescope’s data should be freely available as soon as it is collected — a move that many say would disadvantage early-career scientists and those at smaller institutions who do not have the resources to pounce on and analyse JWST data right away. Telescope operators are also working on a way to get its data to flow more efficiently to Earth through communication dishes, and to fly it in a physical orientation that reduces the risk of micro-meteoroids smashing into and damaging its primary mirror.

But overall the telescope is opening up completely new realms of astronomy, says Rowe-Gurney: “It’s the thing that’s going to answer all the questions that my PhD was trying to find.”

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Rare ‘big fuzzy green ball’ comet visible in B.C. skies, a 50000-year sight

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In the night sky, a comet is flying by Earth for the first time in 50,000 years.

Steve Coleopy, of the South Cariboo Astronomy Club, is offering some tips on how to see it before it disappears.

The green-coloured comet, named C/2022 E3 (ZTF), is not readily visible to the naked eye, although someone with good eyesight in really dark skies might be able to see it, he said. The only problem is it’s getting less visible by the day.

“Right now the comet is the closest to earth and is travelling rapidly away,” Coleopy said, noting it is easily seen through binoculars and small telescopes. “I have not been very successful in taking a picture of it yet, because it’s so faint, but will keep trying, weather permitting.”

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At the moment, the comet is located between the bowl of the Big Dipper and the North Star but will be moving toward the Planet Mars – a steady orange-coloured point of light- in the night sky over the next couple of weeks, according to Coleopy.

“I have found it best to view the comet after 3:30 in the morning, after the moon sets,” he said. “It is still visible in binoculars even with the moon still up, but the view is more washed out because of the moonlight.”

He noted the comet looks like a “big fuzzy green ball,” as opposed to the bright pinpoint light of the stars.

“There’s not much of a tail, but if you can look through the binoculars for a short period of time, enough for your eyes to acclimatize to the image, it’s quite spectacular.”

To know its more precise location on a particular evening, an internet search will produce drawings and pictures of the comet with dates of where and when the comet will be in each daily location.

Coleopy notes the comet will only be visible for a few more weeks, and then it won’t return for about 50,000 years.


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Extreme species deficit of nitrogen-converting microbes in European lakes

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Sampling of Lake Constance water from 85 m depth, in which ammonia-oxidizing archaea make up as much as 40% of all microorganisms

Dr. David Kamanda Ngugi, environmental microbiologist at the Leibniz Institute DSMZ

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Leibniz Institute DSMZ

 

An international team of researchers led by microbiologists from the Leibniz Institute DSMZ-German Collection of Microorganisms and Cell Cultures GmbH in Braunschweig, Germany, shows that in the depths of European lakes, the detoxification of ammonium is ensured by an extremely low biodiversity of archaea. The researchers recently published their findings in the prestigious international journal Science Advances. The team led by environmental microbiologists from the Leibniz Institute DSMZ has now shown that the species diversity of these archaea in lakes around the world ranges from 1 to 15 species. This is of particularly concern in the context of global biodiversity loss and the UN Biodiversity Conference held in Montreal, Canada, in December 2022. Lakes play an important role in providing freshwater for drinking, inland fisheries, and recreation. These ecosystem services would be at danger from ammonium enrichment. Ammonium is an essential component of agricultural fertilizers and contributes to its remarkable increase in environmental concentrations and the overall im-balance of the global nitrogen cycle. Nutrient-poor lakes with large water masses (such as Lake Constance and many other pre-alpine lakes) harbor enormously large populations of archaea, a unique class of microorganisms. In sediments and other low-oxygen environments, these archaea convert ammonium to nitrate, which is then converted to inert dinitrogen gas, an essential component of the air. In this way, they contribute to the detoxification of ammonium in the aquatic environment. In fact, the species predominant in European lakes is even clonal and shows low genetic microdiversity between different lakes. This low species diversity contrasts with marine ecosystems where this group of microorganisms predominates with much greater species richness, making the stability of ecosystem function provided by these nitrogen-converting archaea potentially vulnerable to environmental change.

Maintenance of drinking water quality
Although there is a lot of water on our planet, only 2.5% of it is fresh water. Since much of this fresh water is stored in glaciers and polar ice caps, only about 80% of it is even accessible to us humans. About 36% of drinking water in the European Union is obtained from surface waters. It is therefore crucial to understand how environmental processes such as microbial nitrification maintain this ecosystem service. The rate-determining phase of nitrification is the oxidation of ammonia, which prevents the accumulation of ammonium and converts it to nitrate via nitrite. In this way, ammonium is prevented from contaminating water sources and is necessary for its final conversion to the harmless dinitrogen gas. In this study, deep lakes on five different continents were investigated to assess the richness and evolutionary history of ammonia-oxidizing archaea. Organisms from marine habitats have traditionally colonized freshwater ecosystems. However, these archaea have had to make significant changes in their cell composition, possible only a few times during evolution, when they moved from marine habitats to freshwaters with much lower salt concentrations. The researchers identified this selection pressure as the major barrier to greater diversity of ammonia-oxidizing archaea colonizing freshwaters. The researchers were also able to determine when the few freshwater archaea first appeared. Ac-cording to the study, the dominant archaeal species in European lakes emerged only about 13 million years ago, which is quite consistent with the evolutionary history of the European lakes studied.

Slowed evolution of freshwater archaea
The major freshwater species in Europe changed relatively little over the 13 million years and spread almost clonally across Europe and Asia, which puzzled the researchers. Currently, there are not many examples of such an evolutionary break over such long time periods and over large intercontinental ranges. The authors suggest that the main factor slowing the rapid growth rates and associated evolutionary changes is the low temperatures (4 °C) at the bottom of the lakes studied. As a result, these archaea are restricted to a state of low genetic diversity. It is unclear how the extremely species-poor and evolutionarily static freshwater archaea will respond to changes induced by global climate warming and eutrophication of nearby agricultur-al lands, as the effects of climate change are more pronounced in freshwater than in marine habitats, which is associated with a loss of biodiversity.

Publication: Ngugi DK, Salcher MM, Andre A-S, Ghai R., Klotz F, Chiriac M-C, Ionescu D, Büsing P, Grossart H-S, Xing P, Priscu JC, Alymkulov S, Pester M. 2022. Postglacial adaptations enabled coloniza-tion and quasi-clonal dispersal of ammonia oxidizing archaea in modern European large lakes. Science Advances: https://www.science.org/doi/10.1126/sciadv.adc9392

Press contact:
PhDr. Sven-David Müller, Head of Public Relations, Leibniz Institute DSMZ-German Collection of Microorganisms and Cell Cultures GmbH
Phone: ++49 (0)531/2616-300
Mail: press@dsmz.de

About the Leibniz Institute DSMZ
The Leibniz Institute DSMZ-German Collection of Microorganisms and Cell Cultures is the world’s most diverse collection of biological resources (bacteria, archaea, protists, yeasts, fungi, bacteriophages, plant viruses, genomic bacterial DNA as well as human and animal cell lines). Microorganisms and cell cultures are collected, investigated and archived at the DSMZ. As an institution of the Leibniz Association, the DSMZ with its extensive scientific services and biological resources has been a global partner for research, science and industry since 1969. The DSMZ was the first registered collection in Europe (Regulation (EU) No. 511/2014) and is certified according to the quality standard ISO 9001:2015. As a patent depository, it offers the only possibility in Germany to deposit biological material in accordance with the requirements of the Budapest Treaty. In addition to scientific services, research is the second pillar of the DSMZ. The institute, located on the Science Campus Braunschweig-Süd, accommodates more than 82,000 cultures and biomaterials and has around 200 employees. www.dsmz.de

PhDr. Sven David Mueller, M.Sc.
Leibniz-Institut DSMZ
+49 531 2616300
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Scientists are closing in on why the universe exists

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Particle astrophysicist Benjamin Tam hopes his work will help us understand a question. A very big one.

“The big question that we are trying to answer with this research is how the universe was formed,” said Tam, who is finishing his PhD at Queen’s University.

“What is the origin of the universe?”

And to answer that question, he and dozens of fellow scientists and engineers are conducting a multi-million dollar experiment two kilometres below the surface of the Canadian Shield in a repurposed mine near Sudbury, Ontario.

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Ten thousand light-sensitive cameras send data to scientists watching for evidence of a neutrino bumping into another particle. (Tom Howell/CBC)

The Sudbury Neutrino Observatory (SNOLAB) is already famous for an earlier experiment that revealed how neutrinos ‘oscillate’ between different versions of themselves as they travel here from the sun.

This finding proved a vital point: the mass of a neutrino cannot be zero. The experiment’s lead scientist, Arthur McDonald, shared the Nobel Prize in 2015 for this discovery.

The neutrino is commonly known as the ‘ghost particle.’ Trillions upon trillions of them emanate from the sun every second. To humans, they are imperceptible except through highly specialized detection technology that alerts us to their presence.

Neutrinos were first hypothesized in the early 20th century to explain why certain important physics equations consistently produced what looked like the wrong answers. In 1956, they were proven to exist.

A digital image of a sphere that is blue and transparent with lines all over.
The neutrino detector is at the heart of the SNO+ experiment. An acrylic sphere containing ‘scintillator’ liquid is suspended inside a larger water-filled globe studded with 10,000 light-sensitive cameras. (Submitted by SNOLOAB)

Tam and his fellow researchers are now homing in on the biggest remaining mystery about these tiny particles.

Nobody knows what happens when two neutrinos collide. If it can be shown that they sometimes zap each other out of existence, scientists could conclude that a neutrino acts as its own ‘antiparticle’.

Such a conclusion would explain how an imbalance arose between matter and anti-matter, thus clarifying the current existence of all the matter in the universe.

It would also offer some relief to those hoping to describe the physical world using a model that does not imply none of us should be here.

A screengrab of two scientists wearing white hard hat helmets, clear googles and blue safety suits standing on either side of CBC producer holding a microphone. All three people are laughing.
IDEAS producer Tom Howell (centre) joins research scientist Erica Caden (left) and Benjamin Tam on a video call from their underground lab. (Screengrab: Nicola Luksic)

Guests in this episode (in order of appearance):

Benjamin Tam is a PhD student in Particle Astrophysics at Queen’s University.

Eve Vavagiakis is a National Science Foundation Astronomy and Astrophysics Postdoctoral Fellow in the Physics Department at Cornell University. She’s the author of a children’s book, I’m A Neutrino: Tiny Particles in a Big Universe.

Blaire Flynn is the senior education and outreach officer at SNOLAB.

Erica Caden is a research scientist at SNOLAB. Among her duties she is the detector manager for SNO+, responsible for keeping things running day to day.


*This episode was produced by Nicola Luksic and Tom Howell. It is part of an on-going series, IDEAS from the Trenches, some stories are below.

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