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Four revelations from the Webb telescope about distant galaxies –



Astronomers found these two distant galaxies in the same small part of the sky. They estimate that the one on the right is from 300 million years after the Big Bang.Credit: JWST GLASS Survey NASA/CSA/ESA/STScI; Pascal Oesch/University of Geneva

NASA built its state-of-the-art James Webb Space Telescope to peer into the distant Universe and back towards the dawn of time — and it’s already doing so spectacularly. In the two weeks since Webb’s first science images and data became available for astronomers to work with, they have reported a flood of preliminary discoveries, including multiple contenders for what could be the most distant galaxy ever seen.

Webb’s images reveal a wealth of galaxies glimmering in the distant cosmos, appearing as they did just a few hundred million years after the Big Bang 13.8 billion years ago. The telescope’s astonishingly sharp pictures have shattered astronomers’ preconceptions about the early Universe.

“We had in mind an idea of what galaxies at these [distances] would look like, and how much detail we’d be able to see, but I think the reality is just kind of blowing our mind,” says Jeyhan Kartaltepe, an astronomer at the Rochester Institute of Technology in New York.

Here are some things astronomers are learning from Webb’s first observations.

There are an awful lot of galaxies way out there.

Because Webb detects infrared light, and because the expansion of the cosmos stretches light to redder wavelengths, the telescope is well suited to spotting galaxies that formed early in the Universe’s history. In its first observing programmes, which kicked off in June, Webb discovered many distant galaxies that lie beyond the reach of other observatories, such as the Hubble Space Telescope.

“It suggests what many of us have been arguing, that there are galaxies out there beyond what we saw with Hubble,” says Richard Ellis, an astronomer at University College London.

The era of early galaxies began at ‘cosmic dawn’, starting perhaps around 250 million years after the Big Bang, when the first stars formed and lit up the Universe. Later generations of stars amassed themselves into galaxies, which are the faint red blobs that Webb is beginning to discover.

Many of the Webb images are peppered with never-before-seen galaxies in the distant Universe. “There’s hardly any empty space that doesn’t have something,” Kartaltepe says.

One study combed through data from many of the distant galaxy fields Webb has observed so far, to analyse the rate at which stars formed in the early Universe. It found 44 previously unknown galaxies stretching back to within 300 million years of the Big Bang. Combined with 11 previously known galaxies, the findings show that there was a significant population of galaxies forming stars in the early Universe1. The results “re-affirm the enormous potential of forthcoming larger [Webb] programmes to transform our understanding of the young Universe,” wrote the team, led by Callum Donnan of the University of Edinburgh, UK, in a paper on the arXiv preprint server.

Many galaxies are competing for the ‘most distant’ title.

Perhaps the highest-profile rush is the stampede of research teams vying to identify the most distant galaxy in the Webb data. A number of candidates have been spotted that will need to be confirmed through further studies, but all of them would break Hubble’s record for the most-distant galaxy, which dates to around 400 million years after the Big Bang2,3.

Pixellated image of Maisie’s Galaxy

Maisie’s Galaxy: Astronomer Steven Finkelstein nicknamed this distant galaxy after his daughter. He estimates that it is from 280 million years after the Big Bang.Credit: Steven Finkelstein (UT Austin), Micaela Bagley (UT Austin), Casey Papovich (Texas A&M) and the CEERS Team

One contender popped up in a Webb survey called GLASS that included another, slightly less faraway galaxy in the same image4. “The fact that we found these two bright galaxies, that was really a surprise,” says Marco Castellano, an astronomer at the National Institute for Astrophysics in Rome. He and his colleagues weren’t expecting to find any galaxies that distant in this small part of the sky. A second team also independently spotted the two galaxies5.

Astronomers characterize the distance of galaxies with a measure known as redshift, which quantifies how much a galaxy’s light has been shifted to redder wavelengths; the higher the redshift, the more distant the galaxy. The GLASS candidate has a redshift of about 13. But on 25 and 26 July, days after astronomers reported the GLASS galaxies, papers claiming even higher redshifts flooded the arXiv preprint server. “This is just the beginning of the beginning,” says Rohan Naidu, an astronomer at the Harvard-Smithsonian Center for Astrophysics in Cambridge, Massachusetts.

One candidate, at a redshift of 14, emerged in a survey called CEERS, one of Webb’s highest-profile early projects. The CEERS principal investigator, Steven Finkelstein at the University of Texas at Austin, nicknamed the object Maisie’s Galaxy, after his daughter6. Another study looked at the very first deep-field image from Webb, released by US President Joe Biden on 11 July, and found two potential galaxies at a redshift of 16, which would place them just 250 million years after the Big Bang7. And other arXiv papers speculate on other candidates, even out to redshifts of 208.

Some early galaxies are surprisingly complex.

Webb’s distant galaxies are also turning out to have more structure than astronomers had expected.

One study of Webb’s first deep-field image found a surprisingly large number of distant galaxies that are shaped like disks9. Using Hubble, astronomers had concluded that distant galaxies are more irregularly shaped than nearby ones, which, like the Milky Way, often display regular forms such as disks. The theory was that early galaxies were more often distorted by interactions with neighbouring galaxies. But the Webb observations suggest there are up to 10 times as many distant disk-shaped galaxies as previously thought.

First deep field image from the James Webb Space Telescope

US President Joe Biden released this deep-field image on 11 July — the first scientific view from Webb revealed publicly.Credit: NASA, ESA, CSA, and STScI

“With the resolution of James Webb, we are able to see that galaxies have disks way earlier than we thought they did,” says Allison Kirkpatrick, an astronomer at the University of Kansas in Lawrence. That’s a problem, she says, because it contradicts earlier theories of galaxy evolution. “We’re going to have to figure that out.”

Another preprint manuscript suggests that massive galaxies formed earlier in the Universe than previously known. A team led by Ivo Labbé of the Swinburne University of Technology in Melbourne, Australia, reports finding seven massive galaxies in the CEERS field, with redshifts between 7 and 1010. “We infer that the central regions of at least some massive galaxies were already largely in place 500 million years after the Big Bang, and that massive galaxy formation began extremely early in the history of the Universe,” the scientists wrote.

And studies of galactic chemistry also show a rich and complicated picture emerging from the Webb data. One analysis of the first deep-field image examined the light emitted by galaxies at a redshift of 5 or greater. (Spectral lines that appear at various wavelengths of light correlate with the chemical elements composing the galaxies.) It found a surprising richness of elements such as oxygen11. Astronomers had thought that the process of chemical enrichment — in which stars fuse hydrogen and helium to form heavier elements — took a while, but the finding that it is under way in early galaxies “will make us rethink the speed at which star formation occurs”, Kirkpatrick says.

Closer galaxies are smaller than expected.

The surprises from Webb continue even a little later in the Universe’s evolution. One study looked at Webb’s observations of ‘cosmic noon’, the period approximately 3 billion years after the Big Bang. This is when star formation peaked in the Universe, and the most light was created.

Wren Suess, an astronomer at the University of California, Santa Cruz, compared Hubble images of galaxies at cosmic noon with Webb images of the same galaxies. At the infrared wavelengths detected by Webb, most of the massive galaxies looked much smaller than they did in Hubble images12. “It potentially changes our whole view of how galaxy sizes evolve over time,” Suess says. Hubble studies suggested that galaxies start out small and grow bigger over time, but the Webb findings hint that Hubble didn’t have the whole picture, and so galaxy evolution might be more complicated than scientists had anticipated.

With Webb just at the beginning of a planned 20-plus years of work, astronomers know they have a lot of changes ahead. “Right now I find myself lying awake at three in the morning,” Kirkpatrick says, “wondering if everything I’ve ever done is wrong.”

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Going back to the moon: 'This is Canada on the world stage, doing big things' –



WASHINGTON — Ask Marc Garneau if he’d go back to space and the first Canadian to ever make the trip doesn’t hesitate: “In a wink.”

It’s another matter entirely, of course, whether the now-retired former astronaut and Quebec MP —  at 74, he finally gave up his seat in the House of Commons just three weeks ago — still has the right stuff.

“You always wonder, when you reach a certain age, whether you would still have that capability that you had when you were younger,” said Garneau, who flew three Space Shuttle missions between 1984 and 2001.


“Having flown three times, I consider myself blessed beyond any reasonable expectation in life.” 

Now the country’s pre-eminent “elder statesman” of space, Garneau has long waited for the day when he’ll be joined in the pantheon of pioneering explorers by the next astronaut to earn the “first Canadian” honorific. 

Who will it be? The world finds out Monday. 

That’s when NASA and the Canadian Space Agency will introduce the four astronauts — three from the U.S., one from Canada — who will steer the next stage of an ambitious plan to establish a long-term presence on the moon. 

Scheduled to blast off as early as November 2024, Artemis II will be the first crewed mission to the moon since the final Apollo mission took flight in 1972. It will also be the first time a Canadian has ventured beyond Earth’s orbit. 

Canada’s astronaut corps currently comprises four people, including David Saint-Jacques, an astrophysicist and medical doctor from Montreal and the only member of the group who’s already been to space. 

Saint-Jacques, 53, flew to the International Space Station in 2018. He was selected for the corps in 2009 alongside Jeremy Hansen, 47, of London, Ont., a colonel and CF-18 pilot in the Royal Canadian Air Force. 

Joining them in 2017 were test pilot and Air Force Lt.-Col. Joshua Kutryk, 41, from Fort Saskatchewan, Alta., and Jennifer Sidey, 34, a mechanical engineer and Cambridge University lecturer from Calgary.  

“I’m not in any way jealous or envious,” Garneau said. “I’m just so excited that we are now taking Canada on what I would say is a major, major step forward.” 

It’s not quite the giant leap of 1969, but it’s close — about 7,400 kilometres away, to be precise. 

The four Artemis astronauts will encircle their home planet before sling-shotting into deep space for a figure-8 manoeuvre around the moon, making Canada and the U.S. the only two countries to ever pass over the dark side of the lunar surface.

“When I think back on 1984, when I first flew, we didn’t know what might happen after that,” Garneau said. 

“To now have the opportunity for Canada to be only the second country to have an astronaut go on a lunar mission — this is extraordinary.” 

It’s also the product of a tremendous amount of hard work and investment, said Western University professor Gordon Osinski, director of the school’s Institute for Earth and Space Exploration. 

Osinski spent the bulk of last week in Houston, taking part in simulated spacewalks to better learn and understand how best to conduct the geological work future astronauts will be required to do on the lunar surface.

While that research isn’t directly related to Artemis, it’s bound to be a key factor down the road as the ultimate mission continues to evolve into something that will bear little resemblance to its Apollo ancestors. 

“I can do field geology on Earth with a Star Trek-like instrument that tells me the chemistry of a rock. It wasn’t even imagined 50 years ago,” Osinski said. 

“So as we progress in the whole Artemis program, I think you’ll really see 21st-century space exploration like we might imagine from Star Trek and things.”

Even now, Osinski is still incredulous that Canada managed to secure a spot on Artemis II — and he credits everything from the country’s geographical and economic ties with the U.S. to the ongoing work of the Canadian astronaut corps. 

Then there’s the Canadarm, the articulated remote manipulators that became a fixture of Space Shuttle and International Space Station missions and a point of national pride for countless Canadians of a certain age.

“The U.S. has let go and said, ‘OK, Canada, we trust you enough that we’ll literally put the lives of our astronauts in your hand,'” Osinski said. 

“So that trust maybe goes a long way to explain how we did it.”

 The plan is to put a man and woman on the moon in 2025 in service of the ultimate goal: eventually dispatching astronauts to Mars. And Canada is expected to play a critical role going forward. 

“We’re going back to the moon. The moon, that’s a big thing,” Innovation Minister François-Philippe Champagne said last week. 

“This is Canada on the world stage, doing big things.”

That, ultimately, could be Artemis II’s biggest legacy for Canada: inspiring the next generation of astronauts in much the same way that Apollo did all those years ago. 

This time, though, the visuals will be spectacular.  

“As much as we get excited about robots and the Canadarm and things, having a personal experience in that could be a huge moment and a big milestone for the Canadian space program,” Osinski said. 

“There’s just something about having an astronaut do that.”

This report by The Canadian Press was first published April 2, 2023.

James McCarten, The Canadian Press

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After sunset, see the 5 planets in the sky



This chart shows a westward view after sunset on March 30, 2023. Jupiter is getting harder to see, and the Sun is falling into the setting light. But Mercury will rise in the west — every evening — and rise throughout early April. Note that Uranus is close to Venus, but not shown. We show Uranus in the chart below. By way of illustration Used with permission.

How to see 5 planets

This week (late March 2023), you can see five planets lined up in our evening sky: Venus and Uranus, Jupiter and Mercury and Mars. Gianluca Massi of the Virtual Telescope Project in Rome, Italy, showed them through a telescope earlier today (March 29). To enjoy his presentation, watch the video below. In addition, you can see them in the sky, perhaps, if your sky conditions are very good, and you have a sharp eye.

As soon as the sun sets, the planets are positioned in a gentle arc across the evening sky, following the sun’s path across our sky. Likewise, the Moon and the planets also follow the eclipse.

How can we see the planets? Go out around sunset and look west. Among them you can easily spot the bright planet Venus.

Then use binoculars to scan the planet Uranus next to Venus.


Then aim your binoculars low in the sky, near the point where the sun is setting. That is where you will find Jupiter and Mercury.

Then look high in the sky — still see the eclipse or the path of the Sun — to Mars.


Guide to Planetary Viewing

Venus and Uranus. Of these five planets, Venus is the brightest and Uranus is the dim. These two are close together in the sky. Venus is easily visible to the eye. It is the first “star” (actually, planet) to come into view. Uranus shines at +5.8 magnitudes. This is theoretically obvious. But, in practice, you need a dark sky and a telescope to find it. It was roughly 1.5 degrees or three moon widths from Venus earlier this week. Uranus will be closest to Venus on Thursday, March 30.

Thursday and Wednesday. Jupiter is the 2nd brightest planet. But it is now near sunset and visible only in bright twilight. Bright twilight skies make Jupiter more difficult to find. But Jupiter is still visible to the naked eye very close to sunset. And Wednesday? It is fainter than Jupiter (though still brighter than most stars). But it is near sunset. Shortly after sunset, start looking for the pair on the western horizon. You need clear skies and an unobstructed western view to catch them. A telescope should help. They disappear only 30 minutes after sunset. So, when the sun sets, the clock chimes.

tuesday, now the 5th planet in the evening sky, was easy to spot earlier this week because it’s not far from the Moon in our sky’s dome. A bright red light near the moon on Tuesday evening, March 28, 2023. Mars is bright. It is brighter than most stars. And it is clearly red. Even after the sun goes away, you can still spot Mars by its color and by the fact that it doesn’t shine like stars.

Some inventor charts

March 30, Venus and Uranus through binoculars. Venus at upper right, large and bright.March 30, Venus and Uranus through binoculars. Venus at upper right, large and bright.
On the evening of March 30, 2023, bright Venus transits dim Uranus. In other words, these 2 worlds are very close on March 30. Assuming you have a dark sky, standard telescopes can easily show Uranus next to Venus. Illustration by John Jardine Gauss/EarthSky.
5 Planets: Astrology Chart for March 31 showing Nakshatras. Planets and Moon align at sunset.5 Planets: Astrology Chart for March 31 showing Nakshatras. Planets and Moon align at sunset.
This chart shows the view looking west after sunset on March 31, 2023. Can you catch Jupiter in the sunset light? Every evening, Mercury becomes superlative in early April. Note that Uranus is close to Venus, but not shown. By way of illustration Used with permission.
5 Planets: Astrology chart for March 29 showing stars. The planets and the moon align at night.5 Planets: Astrology chart for March 29 showing stars. The planets and the moon align at night.
Want to see 5 planets tonight? Be ready for a challenge. This chart shows the view looking west after sunset on March 29, 2023. As the days pass, it becomes harder and harder for Jupiter to fall into the setting sun. But Mercury will rise in the west — every evening — and rise throughout early April. Note that Uranus is close to Venus, but not shown. By way of illustration Used with permission.
Two nearly half-light moons, 1 to the right near the Red Spot (Mars) and the other to the left near the stars named Castor and Pollux.Two nearly half-light moons, 1 to the right near the Red Spot (Mars) and the other to the left near the stars named Castor and Pollux.
Here is a chart showing both March 28 and March 29. See how the Moon moves with Mars? Check out the twin stars Castor and Pollux in Gemini the Twins. Illustration by John Jardine Gauss/EarthSky.

Visit for accurate views from your location.

Bottom line: You have a chance to see five planets tonight and throughout this week. Here are illustrations and information, including where to look in the video.


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Artemis 2’s Canadian astronaut got their moon mission seat with ‘potato salad’



It took four years of negotations for Canada to get a seat on NASA’s upcoming moon mission.

That mission, Artemis 2, will send a Canadian and three Americans around the moon no sooner than November 2024. The Canadian seat comes courtesy of a big contribution to NASA’s Artemis program: Canadarm3, a robotic arm that will service the planned Gateway moon-orbiting space station. (The identities of the Artemis 2 crewmembers are currently unknown but will be revealed on Monday, April 3, in a live NASA event that you can watch here at

Canadarm3 was announced in 2019 as part of a big push in Canadian federal government circles to reprioritize space exploration. The government pledged US $1.56 billion USD in space spending over 24 years ($2.05 billion CAD under 2019 exchange rates). That’s $65 million USD a year, a fairly significant amount for a space agency that specializes in niche projects.

Much of that Canadian Space Agency (CSA) money was for Canadarm3, but some was also earmarked for a business incubator known as the Lunar Exploration Acceleration Program (LEAP). Other support went to food and health tech development contests designed to assist future deep space astronauts.


Getting all that funding and securing a seat on Artemis 2, however, took four years of behind-the-scenes negotiations. To introduce what happened, let’s talk about something that may not sound all that space-y at first: potato salad.

Canada is a powerful tech specialist that has been supplying highly capable space robotics since 1981 — Canadarm for the space shuttle program; Canadarm2 for the International Space Station (ISS), along with a “handy robot” named Dextre; and Canadarm3, which will be built by the company MDA. These are all crucial tools used for applications such as spacewalking, satellite repairs and space station servicing.

Ken Podwalski, a senior CSA official involved with the Artemis 2 and Gateway negotiations, likens the reputation of Canada’s space robotics to the dinner guest who comes armed with a divine side dish: “People look at Canada and say, ‘Canada, you guys make the best potato salad, bar none. It’s the best potato salad you can get. Nobody does it like you.'”

His confidence comes from decades of space experience. NASA’s Hubble Space Telescope, for example, would not be running today without Canadarm, which was used on five space shuttle servicing missions to the iconic observatory from 1993 to 2009. Nor would the ISS exist in its current form without Canadarm2, which berths cargo ships, assists in construction and even starred in a spectacular 2007 emergency spacewalk to fix a torn ISS solar panel.


NASA astronaut Scott Parazynski during a tricky International Space Station solar array repair in 2007. He rode a combination of Canadian robotics to get to the distant site: the Canadarm2 grasped a modified Canadarm to extend the robotic reach as far as possible. (Image credit: NASA )

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But in 2015, when the future of the ISS collaboration was being discussed within Canada, the U.S. and other nations, there were lots of questions about what would happen next. Canada was just changing over from a Conservative to a Liberal government for the first time in nearly a decade, following the 2015 election.

The U.S. was on the eve of the 2016 election, which brought in a new presidential administration as well. Numerous ideas were batted about concerning the direction of NASA’s human spaceflight program over the coming years. Would the agency work toward a crewed visit to an asteroid? A moon mission? How quickly and with whom? And within Canada, no space plan for government spending direction had been formulated for many years, making roadmaps similarly uncertain — until a high-level strategy document came out in 2019.

The multinational space groups Canada is a part of all agreed on one thing, Podwalski said: Mars was the ultimate destination. The question simply came down to which pathway to take. The CSA created its own planning group that used the ISS agreements as a starting point. Gateway, though changing design and scope periodically, was a solid enough target to plan discussions with NASA during the 2015 to 2018 negotiations, he said.

“We were going through this quite intensive time. We were doing presentations with the partners and trying to understand what the right fit was,” Podwalski recalled. “We were [also] doing presentations with our government, trying to make sure that we’re taking the right approach.”


NASA and other international partners have agreed that eventually they want to send humans to Mars, but the pathway has been under negotiation for many years. (Image credit: NASA)

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Building the new Canadarm3 was established as the primary aim. Podwalski, citing what he calls the “potato salad speech” he brings out in such planning meetings, said he always told people that focus was essential.

“Everybody expects Canada to bring the potato salad,” he said. “The potato salad gets you in the door, no problem … and it doesn’t stop you from bringing anything else. You’re now a part of the party. Now’s a good time to bring up other things.”

He thus urged his collaborators to deprioritize expensive and newer work that Canada could undertake, such as space modules or large rovers. But they also sought other avenues where modest investments could have a powerful impact and involve many smaller companies in related industries to space. Through these conversations, a mini moon rover (announced in 2021), a lunar utility vehicle (announced in the Canadian federal budget on March 28) and the CSA LEAP incubator program (renewed in the 2023 federal budget) all eventually came to be as well.

Canadarm3 was also designed to align with the priorities of the Canadian government. Serving remote communities in the north, especially Indigenous groups, through spinoff medical technology? Check. Continuing to grow Canada’s artificial intelligence community, a key tech direction for the country? Another big check, as Canadarm3 will be autonomously operating without astronaut crews nearby for at least 11 months a year. Preparing for Mars? Absolutely, as the artificial intelligence and robotics will also be beneficial on a more faraway planet, Podwalski said.


A visualization of the crew segment of the NASA-led lunar Gateway station. Gateway’s design will likely continue to evolve as new hardware becomes available. (Image credit: ESA/NASA/ATG Medialab)

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Podwalski emphasized how important it was to stay flexible through the negotiations, which extended through several U.S. election and Canadian cycles across 2015 to 2018, not to mention policy changes in the European Space Agency, the Japan Aerospace Exploration Agency and other partners.

“It is difficult to pull together these multibillion-dollar programs and get all these partners with all their own agendas about what they want to do in space, what technologies they want to develop and what they want to do with their industry,” he said.

Formulations also will continue to change on the key hardware, he emphasized, and negotiations are always undertaken with that flexibility in mind. For example, he said, it’s possible that Gateway may alter again after SpaceX‘s Starship achieves its first spaceflight as soon as this month, given that Starship could carry a considerable amount of cargo to lunar realms.

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But for Canada, the benefits from Canadarm3’s “potato salad” approach have been considerable so far. The Artemis 2 seat, when offered by NASA, met the CSA’s goal of having an early moon mission with an astronaut on board to build industry and scientific momentum for other moon ventures, Podwalski said.

So far, NASA has also promised a long-duration Gateway mission to Canada sometime in the future. Other astronaut lunar journeys may come, including a landing mission, in negotiations down the road.

The ISS journey will continue alongside Artemis, too. Canada last month committed to extending its ISS participation to 2030 alongside other partners who agreed to that last year, most crucially NASA. (Russia has said it aims to exit the ISS partnership sometime after 2024.) Canada will also fly an astronaut to the ISS again in 2024 or 2025, the Canadian federal budget confirmed a few days ago.

Podwalski urged the community to keep watching for new announcements. “We’re a partner in good standing,” he said of the ISS and Artemis consortiums. “We’re part of the initial [moon] foray; we’re part of the trailblazers. It really does position Canada in a good way.”



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