NASA capsule flies over Apollo landing sites, heads home - CTV News

CAPE CANAVERAL, Fla. -

NASA's Orion capsule and its test dummies swooped one last time around the moon Monday, flying over a couple Apollo landing sites before heading home.

Orion will aim for a Pacific splashdown Sunday off San Diego, setting the stage for astronauts on the next flight in a couple years.

The capsule passed within 80 miles (130 kilometres) of the far side of the moon, using the lunar gravity as a slingshot for the 237,000-mile (380,000-kilometre) ride back to Earth. It spent a week in a wide, sweeping lunar orbit.

Once emerging from behind the moon and regaining communication with flight controllers in Houston, Orion beamed back photos of a close-up moon and a crescent Earth -- Earthrise -- in the distance.

"Orion now has its sights set on home," said Mission Control commentator Sandra Jones.

The capsule also passed over the landing sites of Apollo 12 and 14. But at 1,200 miles (1,900 kilometres) up, it was too high to make out the descent stages of the lunar landers or anything else left behind by astronauts more than a half-century ago. During a similar flyover two weeks ago, it was too dark for pictures. This time, it was daylight.

Deputy chief flight director Zebulon Scoville said nearby craters and other geologic features would be visible in any pictures, but little else.

"It will be more of a tip of the hat and a historical nod to the past," Scoville told reporters last week.

The three-week test flight has exceeded expectations so far, according to officials. But the biggest challenge still lies ahead: hitting the atmosphere at more than 30 times the speed of sound and surviving the fiery reentry.

Orion blasted off Nov. 16 on the debut flight of NASA's most powerful rocket ever, the Space Launch System or SLS.

The next flight -- as early as 2024 -- will attempt to carry four astronauts around the moon. The third mission, targeted for 2025, will feature the first lunar landing by astronauts since the Apollo moon program ended 50 years ago this month.

Apollo 17 rocketed away Dec. 7, 1972, from NASA's Kennedy Space Center, carrying Eugene Cernan, Harrison Schmitt and Ron Evans. Cernan and Schmitt spent three days on the lunar surface, the longest stay of the Apollo era, while Evans orbited the moon. Only Schmitt is still alive.

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2022-12-06 17:17:10Z
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Asymmetry Detected in the Distribution of Galaxies - Quanta Magazine

Introduction

Physicists believe they have detected a striking asymmetry in the arrangements of galaxies in the sky. If confirmed, the finding would point to features of the unknown fundamental laws that operated during the Big Bang.

“If this result is real, someone’s going to get a Nobel Prize,” said Marc Kamionkowski, a physicist at Johns Hopkins University who was not involved in the analysis.

As if playing a cosmic game of Connect the Dots, the researchers drew lines between sets of four galaxies, constructing four-cornered shapes called tetrahedra. When they had built every possible tetrahedron from a catalog of 1 million galaxies, they found that tetrahedra oriented one way outnumber their mirror images.

A hint of the imbalance between tetrahedra and their mirror images was first reported by Oliver Philcox, an astrophysicist at Columbia University in New York, in a paper published in Physical Review D in September. In an independent analysis conducted simultaneously that’s now undergoing peer review, Jiamin Hou and Zachary Slepian of the University of Florida and Robert Cahn of Lawrence Berkeley National Laboratory detected the asymmetry with a level of statistical certainty that physicists usually consider definitive.

But with such a blockbuster finding — and one that’s still under review — experts say caution is warranted.

“There’s no obvious reason that they’ve made a mistake,” said Shaun Hotchkiss, a cosmologist at the University of Auckland. “That doesn’t mean that there isn’t a mistake.”

The putative imbalance violates a symmetry called “parity,” an equivalence of left and right. If the observation withstands scrutiny, physicists think it must reflect an unknown, parity-violating ingredient in the primordial process that sowed the seeds of all the structure that developed in our universe.

“It’s an incredible result — really impressive,” Kamionkowski said. “Do I believe it? I’m going to wait to really celebrate.”

Left-Handed Universe

Parity was once a cherished symmetry of physics. But then, in 1957, the Chinese American physicist Chien-Shiung Wu’s nuclear decay experiments revealed that our universe indeed has a slight handedness to it: Subatomic particles involved in the weak nuclear force, which causes nuclear decay, are always magnetically oriented in the opposite direction from the one they move in, so that they spiral like the threads of a left-handed screw. The mirror-image particles — the ones like right-handed screws — don’t feel the weak force.

Wu’s revelation was shocking. “We are all rather shaken by the death of our well-beloved friend, parity,” the physicist John Blatt wrote in a letter to Wolfgang Pauli.

The left-handedness of the weak force has subtle effects that couldn’t have influenced the cosmos on galactic scales. But ever since Wu’s discovery, physicists have sought other ways in which the universe differs from its mirror image.

If, for instance, some primordial parity violation was in effect when the universe was in its infancy, it might have imprinted a twist onto the structure of the cosmos.

At or near the time of the universe’s birth, a field known as the inflaton is thought to have permeated space. A roiling, boiling medium where inflaton particles continuously bubbled up and disappeared, the inflaton field was also repulsive; for the brief time it may have existed, it would have caused our universe to rapidly expand to 100 trillion trillion times its original size. All of those quantum fluctuations of particles in the inflaton field were flung outward and frozen into the cosmos, becoming variations in the density of matter. The denser pockets continued to gravitationally coalesce to produce the galaxies and large-scale structure we see today.

In 1999, researchers including Kamionkowski considered what would happen if more than one field was present before this explosion. The inflaton field could have interacted with another field that could produce right-handed and left-handed particles. If the inflaton treated right-handed particles differently than the left-handed ones, then it could have preferentially created particles of one handedness over the other. This so-called Chern-Simons coupling would have imbued the early quantum fluctuations with a preferred handedness, which would have evolved into an imbalance of left-handed and right-handed tetrahedral arrangements of galaxies.

As for what the additional field might be, one possibility is the gravitational field. In this scenario, a parity-violating Chern-Simons interaction would occur between inflaton particles and gravitons — the quantum units of gravity — which would have popped up in the gravitational field during inflation. Such an interaction would have created a handedness in the density variations of the early universe and, consequently, in today’s large-scale structure.

Introduction

In 2006, Stephon Alexander, a physicist now at Brown University, suggested that Chern-Simons gravity could also potentially solve one of the biggest mysteries in cosmology: why our universe contains more matter than antimatter. He surmised that the Chern-Simons interaction could have yielded a relative abundance of left-handed gravitons, which would in turn preferentially create left-handed matter over right-handed antimatter.

Alexander’s idea remained relatively obscure for years. When he heard about the new findings, he said, “that was a big surprise.”

Tetrahedra in the Sky

Cahn thought the possibility of solving the matter-antimatter asymmetry puzzle with parity violation in the early universe was “speculative, but also provocative.” In 2019, he decided to look for parity violation in a catalog of galaxies in the Sloan Digital Sky Survey. He didn’t expect to find anything but thought it would be worth a check.

To test whether the galaxy distribution respects or violates parity, he and his collaborators knew they needed to study tetrahedral arrangements of four galaxies. This is because the tetrahedron is the simplest three-dimensional shape, and only 3D objects have a chance at violating parity. To understand this, consider your hands. Because hands are 3D, there’s no way to rotate a left one to make it look like a right one. Flip your left hand over so that the thumbs of both hands are on the left, and your hands still look different — the palms face opposite ways. By contrast, if you trace a left hand on a sheet of paper and cut out the 2D image, flipping the cutout over makes it look like a right hand. The cutout and its mirror image are indistinguishable.

In 2020, Slepian and Cahn came up with a way of defining the “handedness” of a tetrahedral arrangement of galaxies in order to compare the number of left-handed and right-handed ones in the sky. First they took a galaxy and looked at the distances to three other galaxies. If the distances increased in the clockwise direction like a right-handed screw, they called the tetrahedron right-handed. If the distances increased going counterclockwise, it was left-handed.

To determine whether the universe as a whole has a preferred handedness, they had to repeat the analysis for all tetrahedra constructed from their database of 1 million galaxies. There are nearly 1 trillion trillion such tetrahedra — an intractable list to handle one at a time. But a factoring trick developed in earlier work on a different problem allowed the researchers to look at the parity of tetrahedra more holistically: Rather than assembling one tetrahedron at a time and determining its parity, they could take each galaxy in turn and group all other galaxies according to their distances from that galaxy, creating layers like the layers of an onion. By expressing the relative positions of galaxies in each layer in terms of mathematical functions of angles called spherical harmonics, they could systematically combine sets of three layers to make collective tetrahedra.

The researchers then compared the results to their expectations based on parity-preserving laws of physics. Hou led this step, analyzing fake catalogs of galaxies that had been generated by simulating the evolution of the universe starting from tiny, parity-preserving density variations. From these mock catalogs, Hou and her colleagues could determine how the tally of left- and right-handed tetrahedra randomly varies, even in a mirror-symmetric world.

The team found a “seven-sigma” level of parity violation in the real data, meaning that the imbalance between left- and right-handed tetrahedra was seven times as large as could be expected from random chance and other conceivable sources of error.

Kamionkowski called it “incredible that they were able to do that,” adding that “technically, it’s absolutely astounding. It’s a really, really, really complicated analysis.”

Philcox used similar methods (and had co-authored some earlier papers proposing such an analysis with Hou, Slepian and Cahn), but he made some different choices — for example, grouping the galaxies into fewer layers than Hou and colleagues, and omitting some problematic tetrahedra from the analysis — and therefore found a more modest 2.9-sigma violation of parity. The researchers are now studying the differences between their analyses. Even after extensive efforts to understand the data, all parties remain cautious.

Corroborating Evidence

The surprising finding hints at new physics that could potentially answer long-standing questions about the universe. But the work has only just begun.

First physicists need to verify (or falsify) the observation. New, ambitious galaxy surveys on which to repeat the analysis are already underway. The ongoing Dark Energy Spectroscopic Instrument survey, for instance, has logged 14 million galaxies so far and will contain more than 30 million when it’s completed. “That’ll give us an opportunity to look at this in much greater detail with much better statistics,” said Cahn.

Introduction

Moreover, if the parity-violating signal is real, it could show up in data other than the distribution of galaxies. The oldest light in the sky, for example — a bath of radiation known as the cosmic microwave background, left over from the early universe — provides our earliest snapshot of spatial variations in the cosmos. The dappled pattern of this light should contain the same parity-violating correlations as the galaxies that formed later. Physicists say it should be possible to find such a signal in the light.

Another place to look will be the pattern of gravitational waves that may have been generated during inflation, called the stochastic gravitational wave background. These corkscrew-like ripples in the space-time fabric can be right-handed or left-handed, and in a parity-preserving world, they would contain equal amounts of each. So if physicists manage to measure this background and find that one handedness is favored, this would be an unambiguous, independent check of parity-violating physics in the early universe.

As the search for corroborating evidence begins, theorists will study models of inflation that could have produced the signal. With Giovanni Cabass, a theoretical physicist at the Institute for Advanced Study in Princeton, New Jersey, Philcox recently used his measurement to test a slew of parity-violating models of inflation, including those of the Chern-Simons type. (They can’t yet say with certainty which model, if any, is correct.)

Alexander has also refocused his efforts on understanding Chern-Simons gravity. With collaborators including Kamionkowski and Cyril Creque-Sarbinowski of the Flatiron Institute’s Center for Computational Astrophysics, Alexander has begun working out subtle details about how Chern-Simons gravity in the early universe would influence the distribution of today’s galaxies.

“I was kind of like the lone soldier pushing this stuff for a while,” he said. “It’s good to see people taking an interest.”

Editor’s Note: The Flatiron Institute is funded by the Simons Foundation, which also supports this editorially independent magazine. In addition, Oliver Philcox receives funding from the Simons Foundation.

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2022-12-05 15:17:43Z
CBMiW2h0dHBzOi8vd3d3LnF1YW50YW1hZ2F6aW5lLm9yZy9hc3ltbWV0cnktZGV0ZWN0ZWQtaW4tdGhlLWRpc3RyaWJ1dGlvbi1vZi1nYWxheGllcy0yMDIyMTIwNS_SAQA

Clamshells Face the Acid Test - Hakai Magazine

Article body copy

It’s low tide in Bodega Bay, north of San Francisco, California, and Hannah Hensel is squishing through thick mud, on the hunt for clams. The hinged mollusks are everywhere, burrowed into the sediment, filtering seawater to feed on plankton. But Hensel isn’t looking for living bivalves—she’s searching the mudflat for the shells of dead clams.

“I did lose a boot or two,” she recalls. “You can get sunk into it pretty deep.”

Hensel, a doctoral candidate at the University of California, Davis, is studying shells, which are composed of acid-buffering calcium carbonate, as a tool that could one day help shelled species survive in the world’s rapidly acidifying oceans.

The inspiration for Hensel’s research comes from Indigenous sea gardening practices. On beaches from Alaska to Washington State, First Nations and tribal communities built rock-walled terraces in the intertidal zone to bolster populations of shellfish and other invertebrates. Although these sea gardens have not been documented farther south, clams were also vital sustenance in central California. Coast Miwok and Southern Pomo people harvested clams for food and shaped shells into bead money, says Tsim Schneider, an archaeologist at the University of California, Santa Cruz, and a member of the Federated Indians of Graton Rancheria. “So taking care of your clam beds was actually kind of protecting your vault, your bank,” says Schneider.

In the sea gardens of the Pacific Northwest, caretakers crushed the shells of harvested clams and mixed the fragments back into the beach. Recent research has shown multiple positive effects of this broken shell “hash,” from opening spaces in the sediment so young clams can more easily burrow and grow, to releasing chemical cues that encourage larval clams to settle nearby.

This millennia-old practice may hold the key to addressing a new crisis. As humans burn fossil fuels, oceans are absorbing carbon dioxide from the atmosphere, making seawater more acidic. At lower pH levels, clams and other shellfish struggle to build shells. As their protective structures weaken and dissolve, the animals become vulnerable to damage and predation. But studies suggest that adding shell fragments to clam beds could release carbonate into the water, potentially neutralizing acidity caused by the greenhouse gas.

To find out whether shell hash could help California’s clams survive increasingly acidic conditions, Hensel brought shells from the tidal flat back to the lab, where she crushed them with a mortar and pestle and mixed the fragments into four plastic buckets of sand. Hensel filled these buckets, and four others containing sand alone, with local seawater and added the pinky nail–sized progeny of Pacific littleneck clams collected from Bodega Bay. She bubbled carbon dioxide through the seawater in half of the buckets to increase acidity. With their delicate shells, young clams are thought to be especially vulnerable to acidification.

In the lab, Hannah Hensel bubbles carbon dioxide through the seawater in experimental clam beds to test whether mixing crushed shells into the sediment can protect young Pacific littleneck clams from acidic conditions. Photos courtesy of Hannah Hensel

After 90 days, Hensel dug up all the clams. Comparing the buckets containing more acidic seawater, she observed that the bivalves burrowed in shell hash had grown bigger than the clams in sand alone. Strangely, though, the larger clams were not heavier, and Hensel plans to cross-section the shells to assess whether the new growth was thinner or less dense.

The results inform researchers that shell hash does have a buffering effect under certain conditions, says Leah Bendell, a marine ecologist at Simon Fraser University in British Columbia, who was not involved in the study. “It was a well-done lab experiment.”

Bendell also studies the buffering power of shell hash. Working with the Tsleil-Waututh Nation, Bendell and graduate student Bridget Doyle added shell fragments to clam beds in Burrard Inlet, near Vancouver, British Columbia. In that study, hash reduced pH fluctuations in seawater seeping through the sediment, which can vary markedly with rising and falling tides. Although the reduction was limited to areas with coarse sediments, and the hash did not reduce the overall pH, Bendell sees the results as a hint of something promising. Given a longer period of time, shell hash could have a greater effect on pH in certain clam beds, she says.

Shell hash may not be a panacea for ocean acidification everywhere, but Bendell and Hensel are slowly piecing together how carbonate might help individual beaches weather caustic conditions. Next summer, when Hensel begins adding shell hash to Bodega Bay’s clam beds, she will incorporate another element of traditional sea gardening. Indigenous caretakers regularly tilled clam beds, loosening the sediment and mixing in shell fragments. This repeated digging could bring oxygen to burrowed clams, open more space in the sediments, and alter seawater chemistry, Hensel says, and she plans to measure how the physical process affects both seawater chemistry and clam growth.

Schneider is hopeful that Hensel’s work will improve the health of his community’s clam beds, and the two researchers are discussing ways to involve the Indigenous communities around Bodega Bay. “I think it would just be really rewarding to see community members from my tribe having opportunities to be back out on the landscape to interact with traditional resources in the ways that our ancestors did,” Schneider says.

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2022-12-05 08:01:58Z
CBMiPWh0dHBzOi8vaGFrYWltYWdhemluZS5jb20vbmV3cy9jbGFtc2hlbGxzLWZhY2UtdGhlLWFjaWQtdGVzdC_SAQA

Age of the Sun revealed; here is how old it is - HT Tech

Along with the Sun there are countless otyher objects that formed, such as asteroids, meteors, and planetesimals, which have remained unchanged for billions of years. It is these ojects that help scientists to determine the age of the Sun.  In fact, NASA says, Even Moon rocks work well for this. When astronauts brought them back for scientists to study them, they were able to find out how old they are .(Pixabay)

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2022-12-05 07:05:10Z
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Australia starts building 'momentous' radio telescope - RFI English

Issued on: 05/12/2022 - 06:42

Sydney (AFP) – Australia on Monday started building a vast network of antennas in the Outback, its section of what planners say will eventually become one of the most powerful radio telescopes in the world.

When complete, the antennas in Australia and a network of dishes in South Africa will form the Square Kilometre Array (SKA), a massive instrument that will aim to untangle mysteries about the creation of stars, galaxies and extraterrestrial life.

The idea for the telescope was first conceived in the early 1990s, but the project was plagued by delays, funding issues and diplomatic jockeying.

The SKA Observatory's Director-General Philip Diamond described the beginning of its construction as "momentous".

The telescope "will be one of humanity's biggest-ever scientific endeavours", he said.

Its name is based on the planners' original aim, a telescope that could observe a one-square-kilometre surface, but the current South African and Australian sections will have a combined collecting area of just under half that, according to the observatory.

Both countries have huge expanses of land in remote areas with little radio disturbance -- ideal for such telescopes.

More than 130,000 Christmas tree-shaped antennas are planned in Western Australia, to be built on the traditional lands of the Wajarri Aboriginal people.

They have dubbed the site "Inyarrimanha Ilgari Bundara", or "sharing sky and stars".

"We honour their willingness to share their skies and stars with us as we seek to find answers to some of the most fundamental science questions we face," said Diamond.

The South African site will feature nearly 200 dishes in the remote Karoo region, according to the organisation.

Comparison between radio telescopes is difficult as they operate in different frequencies, according to SKA's planners.

But they have said that the two sites will give SKA higher sensitivity over single-dish radio telescopes because its arrays are spread out, forming a much bigger "virtual dish".

The project will help in "charting the birth and death of galaxies, searching for new types of gravitational waves and expanding the boundaries of what we know about the universe", said telescope director Sarah Pearce.

Danny Price from the Curtin Institute of Radio Astronomy said the telescope would be extremely powerful.

"To put the sensitivity of the SKA into perspective, the SKA could detect a mobile phone in the pocket of an astronaut on Mars, 225 million kilometres away," he said.

The SKA Observatory, headquartered at Jodrell Bank in Britain, has said the telescope should start making scientific observations by the late 2020s.

The organisation has 14 members: Britain, Australia, South Africa, Canada, China, France, Germany, India, Italy, New Zealand, Spain, Sweden, Switzerland, and The Netherlands.

© 2022 AFP

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2022-12-05 05:42:10Z
1682930604

See A ‘Cold Moon’ Occult Mars At Its Biggest, Brightest And Best: The Night Sky This Week - Forbes

Each Monday I pick out the northern hemisphere’s celestial highlights (mid-northern latitudes) for the week ahead but be sure to check my main feed for more in-depth articles on stargazing, astronomy, eclipses and more.

What You Can See In The Night Sky This Week: December 5-11, 2022

This week sees the fourth planet Mars at opposition, something that happens every 26 months as Earth passes the red planet on the inside. It means Mars will be at its biggest, brightest and best as it rises in the east after dark—as you may have noticed in the past few weeks.

However, what happens this week is particularly odd because just as Mars reaches its opposition it will be briefly occulted by the Moon. What a sight! It’s one of the stargazing highlights of the year, but there are a few other Moon-related sights to search for this week.

Tuesday, December 6, 2022: The Moon in Taurus

Stellarium

Tuesday, December 6, 2022: The Moon in Taurus

Look high in the eastern night sky after sunset tonight and you’ll see a 99%-lit waxing gibbous Moon in the constellation of Taurus. On either side of it you’ll see the sparkling Pleiades and the more spread-out Hyades star cluster.

Wednesday, December 7, 2022: A full ‘Cold Moon’ occults Mars at opposition

Stellarium

Wednesday, December 7, 2022: A full ‘Cold Moon’ occults Mars at opposition from North America

Here come two celestial events simultaneously! The rising of December’s full Moon is always a magical event, but the icing on the cake for those in the north and west North America and all of Europe is that the full Moon will occult (move in front of) Mars.

The Moon will cover Mars for viewers across much of North America, northern Mexico, and most of ... [+] Europe, as well as northern Africa. In North America, the sight will unfold in the evening hours of December 7th, whereas it will be a predawn spectacle for those in Europe and northern Africa on December 8th

Gregg Dinderman / Sky & Telescope

Thursday, December 8, 2022: A full ‘Cold Moon’ occults Mars at opposition from Europe

As seen from Europe the Moon will move in front of the red planet in the western sky on Thursday, December 8, 2022. From London, Mars will disappear at 04:58 GMT and reappear at 05:59 GMT.

Saturday, December 10, 2022: Moon in Gemini

Stellarium

Saturday, December 10, 2022: Moon in Gemini

As the waning gibbous Moon rises later tonight, it will be 92% illuminated. Look to the northeast and you’ll see it appear with the two main bright stars of Gemini, Castor and Pollux.

Object of the week: Mars

This week sees the fourth planet Mars at opposition, something that happens every 26 months as Earth passes the red planet on the inside. It means Mars will be at its biggest, brightest and best as it rises in the east after dark—as you may have noticed in the past few weeks.

It’s the perfect time to put a small telescope on the red planet to glimpse its redness and, if you're lucky, its polar ice caps.

Wishing you clear skies and wide eyes.

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2022-12-05 01:00:00Z
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SKA: Construction to begin on world's biggest telescope - BBC

SKA

By Jonathan Amos

BBC Science Correspondent

@BBCAmos

One of the grand scientific projects of the 21st Century begins its construction phase on Monday.

The Square Kilometre Array (SKA) will be the largest radio telescope in the world when completed in 2028.

Split across South Africa and Australia, with a headquarters in the UK, the facility will address the biggest questions in astrophysics.

It will perform the most precise tests of Einstein's theories, and even search for extra-terrestrials.

Delegations from the eight countries leading the project are attending ceremonies in the remote Murchison shire in Western Australia and in the Karoo of South Africa's Northern Cape.

When the festivities are over, the bulldozers will move in.

"This is the moment it becomes real," said Prof Phil Diamond, director general of the Square Kilometre Array Organisation.

"It's been a 30-year journey. The first 10 years were about developing the concepts and ideas. The second 10 was spent doing the technology development. And then the last decade was about detailed design, securing the sites, getting governments to agree to set up a treaty organisation (SKAO) and provide the funds to start," he told BBC News.

• UK to build 'brain' for giant radio telescope
• A $10bn machine in search of the end of darkness
• First picture of monster black hole in our galaxy

SKA

The initial architecture of the telescope will incorporate just under 200 parabolic antennas, or "dishes", as well as 131,000 dipole antennas, which look a little like Christmas trees.

The aim is to construct an effective collecting area measuring hundreds of thousands of square metres.

This will give the SKA unparalleled sensitivity and resolutions as it probes targets on the sky.

The system will operate across a frequency range from roughly 50 megahertz to, ultimately, 25 gigahertz. In wavelength terms, this is in the centimetres to metres range.

This should enable the telescope to detect very faint radio signals coming from cosmic sources billions of light-years from Earth, including those signals emitted in the first few hundred million years after the Big Bang.

One of the SKA's great quests will be to trace the full history of hydrogen, the most abundant element in the Universe.

The telescope should be able to detect hydrogen's presence even before great clouds of it collapsed to form the first stars.

"The SKA is going to contribute to so many areas of astronomy," said Dr Shari Breen, the observatory's head of science operations.

"One would be these 'fast radio bursts' that have been detected. These things output the equivalent of an entire year's worth of energy from our Sun in just a fraction of a second. And we have no idea what they are. How is that possible? Hopefully the SKA will have an answer."

The telescope is being built in areas already used for radio astronomy on a smaller scale.

To expand these sites, however, has required various land agreements, with farmers in the Karoo; and with the Wajarri Yamaji, the Aboriginal title holders in the Murchison.

The Wajarri community have organised Monday's celebration to inaugurate the SKA.

Various procurement contracts will be announced around the ceremonies.

These will take the total financial outlay to date to just under €500m (£430m) - out of an expected final construction budget of €2bn.

SKA

The first major milestone should come in 2024, when four dishes in Australia and six antenna stations in South Africa are made to work seamlessly together as a basic telescope. This proof-of-principle moment will then trigger the array's full roll-out.

By 2028, the SKA will have an effective collecting area of just under 500,000 square metres. But the set-up is such that it can continue growing, perhaps up to the much desired one million square metres, or one square kilometre.

One way this could happen is if more and more countries join the organisation and provide the necessary funds.

The current members are: South Africa, Australia, the UK, China, Italy, Netherlands, Portugal and Switzerland. These countries have ratified the treaty.

France, Spain, and most recently Germany, have got themselves on to the accession path.

Canada, India, Sweden, South Korea and Japan have indicated their intention to join at some point.

"And we're actually in the process of talking to other countries as well, to see what interest they might have in joining the observatory," said Prof Diamond.

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2022-12-05 00:47:01Z
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