Wednesday, July 03, 2024

Researchers Make Breakthrough in Study of Mysterious 2000-Year-Old Computer Found in Shipwreck

Victor Tangermann
Tue, 2 July 2024

Researchers say they've used cutting-edge gravitational wave research to shed new light on a nearly 2,000-year-old mystery.

In 1901, researchers discovered what's now known as the Antikythera mechanism in a sunken shipwreck, an ancient artifact that dates back to the second century BC, making it the world's "oldest computer."

There's a chance you may have spotted a replica, directly inspired by it and featured in the blockbuster "Indiana Jones and the Dial of Destiny" last year.

Well over a century after its discovery, researchers at the University of Glasgow say they've used statistical modeling techniques, originally designed to analyze gravitational waves — ripples in spacetime caused by major celestial events such as two black holes merging — to suggest that the Antikythera mechanism was likely used to track the Greek lunar year.

In short, it's a fascinating collision between modern-day science and the mysteries of an ancient artifact.

In a 2021 paper, researchers found that previously discovered and regularly spaced holes in a "calendar ring" were marked to describe the "motions of the sun, Moon, and all five planets known in antiquity and how they were displayed at the front as an ancient Greek cosmos."

Now, in a new study published in the Oficial Journal of the British Horological Institute, University of Glasgow gravitational wave researcher Graham Woan and research associate Joseph Bayley suggest that the ring was likely perforated with 354 holes, which happens to be the number of days in a lunar year.

The researchers ruled out the possibility of it measuring a solar year.

"A ring of 360 holes is strongly disfavoured, and one of 365 holes is not plausible, given our model assumptions," their paper reads.

The team used statistical models derived from gravitational wave research, including data from the Laser Interferometer Gravitational-Wave Observatory (LIGO), a large-scale physics experiment designed to measure ripples in spacetime millions of light-years from Earth.

The technique, called Bayesian analysis, uses "probability to quantify uncertainty based on incomplete data, to calculate the likely number of holes in the mechanism using the positions of the surviving holes and the placement of the ring’s surviving six fragments," according to a press release about the research.

Surprisingly, the inspiration for the paper came from a YouTuber who has been attempting to physically recreate the ancient mechanism.

"Towards the end of last year, a colleague pointed to me to data acquired by YouTuber Chris Budiselic, who was looking to make a replica of the calendar ring and was investigating ways to determine just how many holes it contained," said Woan in a statement.

"It’s a neat symmetry that we’ve adapted techniques we use to study the universe today to understand more about a mechanism that helped people keep track of the heavens nearly two millennia ago," he added.

It may not amount to the kind of discovery fit for a Hollywood action blockbuster script — but it's an intriguing new ripple in a mystery that has puzzled scientists for over a century nonetheless.

"We hope that our findings about the Antikythera mechanism, although less supernaturally spectacular than those made by Indiana Jones, will help deepen our understanding of how this remarkable device was made and used by the Greeks," Woan said.

More on ancient Greece: The Riddle of the Antikythera Mechanism Deepen

HOMUNCULUS
Work on synthetic human embryos to get code of practice in UK

Ian Sample Science editor
Wed, 3 July 2024

Stem cell-based embryo models made global headlines last summer when researchers said they had created one with a heartbeat and traces of blood.Photograph: Ahmad Gharabli/AFP/Getty Images

Biological models of human embryos that can develop heartbeats, spinal cords and other distinctive features will be governed by a code of practice in Britain to ensure that researchers work on them responsibly.

Made from stem cells, they mimic, to a greater or less extent, the biological processes at work in real embryos. By growing them in the laboratory, scientists hope to learn more about how human embryos develop and respond to their environment, questions that would be impossible to answer with real embryos donated for research.

Scientists have worked on stem cell-based embryo models, or SCBEMs, for many years, but the technology only made global headlines last summer when researchers said they had created one with a heartbeat and traces of blood. Made without the need for eggs or sperm, the ball of cells had some features that would typically appear in the third or fourth week of pregnancy.

The technology, which advocates believe could shed fresh light on potential causes of infertility, is so new that SCBEMs are not directly covered by UK law or regulations. The situation leaves the scientists pursuing the research in an uncomfortable grey area. The new guidelines, drawn up by experts at the University of Cambridge and the Progress Educational Trust, aim to clarify the situation by setting down rules and best practice.

Dr Peter Rugg-Gunn, a member of the code of practice working group, said the guidance took “stem cell-based embryo models out of the grey zone and on to more stable footing”. It should also reassure the public that research is being performed carefully and under proper scrutiny, added Rugg-Gunn, who is a group leader at the Babraham Institute.

The code reminds researchers that there may be “a range of emotional responses” to SCBEMs with heartbeats, spinal cords and other recognisable features, and urges them to be “aware of and sensitive to these concerns, irrespective of whether they are thought to be ethically or legally relevant”.

Under existing UK law, scientists can grow real human embryos donated for research for up to 14 days in the lab, though many argue for the limit to be extended to allow for the study of later stages of embryonic development.

The new guidelines establish an oversight committee that will decide on a case-by-case basis how long specific embryo models can be grown for. The code does not rule out experiments that grow them for more than 14 days, but Roger Sturmey, professor of reproductive medicine at Hull York medical school and chair of the code of practice working group said any such experiments “would have to be very well justified”.

The code prohibits any human SCBEMs from being transferred into the womb of a human or animal, or being allowed to develop into a viable organism in the lab.

Sandy Starr, the deputy director of the Progress Educational Trust, said he expected researchers, funders, research institutes, publishers and regulators to recognise the guidelines. Scientists who worked outside the code would “find it difficult to publish, find funding and face opprobrium from their peers”,” he added.

LA REVUE GAUCHE - Left Comment: Search results for Homunculus

Could Labour use public-private projects to fix England’s hospitals?

Denis Campbell Health policy editor

THE GUARDIAN
Wed, 3 July 2024 a

Patients were evacuated from Stepping Hill hospital in Stockport when some ceilings fell down.Photograph: Manchester Evening News Syndication

Scores of hospitals in England are so old and decrepit that some are falling down. The Conservative government recognised that the NHS needed a massive modernisation of its estate in 2019 when Boris Johnson promised 40 new hospitals by 2030.

But, with public spending due to be tight for the next few years, where would a new government find the money to enable these other projects to go ahead? NHS Providers, which represents trusts, has put forward a new wave of NHS/private-sector partnerships as a potential answer.
Why are so many hospitals in England in such a bad state?

That is partly because so many NHS premises are old, and also because the NHS’s capital budget – which it uses to pay for repairs, build new facilities and buy new equipment such as scanners – has been held down for many years. The cost of all the maintenance repairs needed across the NHS has soared from £4.7bn in 2011-12 to £11.6bn in 2022-23.
But are 40 new hospitals not due to be built by 2030?

Boris Johnson promised in 2019 to do just that, but the new hospitals programme has been beset by cost overruns, confusion over when promised new facilities would finally arrive and a growing number of trusts saying their schemes would not be ready until after 2030.

Plus, while 100 health trusts applied to join, 88 were refused entry, even though parts of some of them – such as Stepping Hill hospital in Stockport – are literally falling down.
So what is NHS Providers proposing?

That the Treasury overhauls the Department of Health and Social Care’s capital departmental expenditure limit (CDEL) rules, which restrict how much money the NHS can spend on building projects, even if some of that money comes from external sources.

Julian Hartley, the head of NHS Providers, wants the new government to apply “fresh thinking” and “imagination” to how the health service can access potentially billions of pounds to build new facilities – by collaborating with property developers, private healthcare companies, pension funds, drug companies, universities and local councils.
Critics claim this would just be a rerun of PFI. What is the concern?

The private finance initiative was used to build an array of new hospitals in the 1990s and 2000s. It was a way of keeping finance used to fund public infrastructure such as schools and hospitals off the Treasury’s balance sheet for reporting public debt.

But under it, developers made profits which, in some cases, were considered obscene. In 2019, the IPPR thinktank calculated that the NHS would end up paying £80bn for £13bn worth of new hospital buildings, so extortionate were the terms their private partners obtained. Trusts spend more than £2bn a year on PFI repayments.

The Commons public accounts committee found in a 2018 report that the “ongoing costs to the institutions at the frontline have been high and the contracts inflexible”. The committee concluded that the “deal is not working for the taxpayer”.

Keep Our NHS Public fears that new joint NHS/private arrangements would again lead to a “need to siphon off taxpayer money to private companies and their shareholders”.
Could Labour act on Hartley’s suggestion?

Wes Streeting, the shadow health secretary, has made clear that he expects the NHS to use the private sector to clear as much of the care backlog as possible. It is unclear, though, if he would see NHS/private sector collaborations as a viable way for health trusts to unlock much-needed funding to enable them to press ahead with building much-needed new facilities.

On Monday, the Health Service Journal asked him if he would relax the Treasury’s CDEL rules, so that trusts could more easily partner with property developers and pension funds on construction projects. He acknowledged trusts faced obstacles accessing capital spending which caused “immense frustration”, and that the shadow chancellor, Rachel Reeves, understood “the scale of the capital challenge in the NHS”.

But, he added, “Treasury rules exist for a reason” and there are “lots of competing demands” for capital, which Labour would have to consider.

However, it is not inconceivable that Labour, which mentioned “partnership” with business 18 times in its manifesto, may be persuaded to explore Hartley’s idea as a way of using private money to rebuild the NHS’s aged, crumbling infrastructure, given the financial position it will inherit.

NHS leader calls for partnership with private sector to build new hospitals

Denis Campbell Health policy editor

THE GUARDIAN
Wed, 3 July 2024

An artist’s impression of Birmingham’s private Harborne hospital, where the local NHS trust has leased 72 beds over two floors.Illustration: Harborne hospital

The NHS must be given the green light to partner with private health firms and property developers to build new hospitals to slash the care backlog, a health service boss has said.

The last Labour government was widely criticised over controversial private finance initiative (PFI) deals to erect scores of new NHS facilities that led to vast profits for major corporations.

But in a major intervention the head of NHS Providers, Julian Hartley, has urged the next administration to relax Treasury rules that limit health service trusts in England from entering into such collaborations and insisted that the NHS has “nothing to fear” from them.

He said: “We need to think outside the box when it comes to solving this double whammy of under-strain public finances and an NHS estate in desperate need of renewal.

“Collaboration with public and private partners such as ethical pension funds, property developers, universities, private healthcare providers and local councils could unlock opportunities for NHS trusts keen to build new hospitals or redevelop existing sites which have been stymied by rigid Treasury rules.”

However, Dr John Puntis of Keep Our NHS Public said most people would find his suggestion “appalling” and that it constituted “a shocking attack on the founding principles of the NHS” as it prepares to mark the 76th birthday of its creation on Friday.

Hartley cited recent partnerships between NHS trusts in Birmingham and Surrey and private health providers to run newly built facilities, which treat NHS and fee-paying patients, as “successful examples of NHS and private sector collaboration. We can draw positive lessons that this is doable, that the NHS and the private sector can work together, and that it supports the interests of NHS services”.

“This doesn’t have to be PFI Two. This is not about privatisation of the NHS; this is about strengthening and supporting the NHS through investment that creates better facilities for patient,” Hartley added.

University Hospitals Birmingham (UHB) trust has been given operational control of 72 of the 122 beds in the Harborne private hospital on its site, which opened in January in a partnership between it and HCA, a large American healthcare firm which operates a network of private hospitals in the UK. UHB did not contribute towards the £100m cost of building the hospital, which provides cancer, cardiac and orthopaedic care, but has taken a lease on two of its eight floors for its own patients.

The extra beds will let people in Birmingham and Solihull get quicker treatment “in world-class facilities, delivered by leading NHS specialists” by cutting its waiting list, it has said.

In a similar move the Royal Surrey NHS trust and Genesis Cancer Care have entered into an arrangement to run a new dedicated cancer centre, which opened in Guildford, Surrey in March. The £30m facility is providing oncology and radiotherapy to NHS and private patients.

Hartley urged whoever are the chancellor and health secretary after the UK general election to “have an open mind” on NHS tie-ups involving major injections of capital from drug companies, pension funds and universities. The new government should see the new wave of hospitals that would ensue as a boost to the economy and a way of the public sector leveraging private sources of funding at a time when government spending is likely to remain tight, he said.

He wants the Treasury to review the Department of Health and Social Care’s capital departmental expenditure limit (CDEL), which restricts how much health trusts and the NHS overall can spend on capital projects, even if some of the money has come from external sources. The backlog of repairs needed across the NHS in England has ballooned in recent years to £11.6bn.

Keir Starmer and the shadow health secretary, Wes Streeting, have said that under a Labour government the NHS will use the private sector as much as it can to cut a backlog that has spiralled to 7.6m procedures. Acting on Hartley’s idea would risk angering those anxious about NHS privatisation.

Hartley highlighted that scores of NHS trusts were left unable to rebuild or replace sometimes dangerously decrepit facilities when, of the 100 that applied to join the New Hospitals Programme, the scheme to implement the pledge of the then prime minister, Boris Johnson, to build “40 new hospitals” by 2030, only 40 were given entry because numbers were capped.

David Hare, chief executive of the Independent Healthcare Providers Network, which represents private health providers, said: “There is huge appetite in the independent sector to partner with the NHS and bring much-needed new capital, capacity and capability to support better access to NHS services for patients free at the point of use.”

But David Rowland, director of the Centre for Health and the Public Interest thinktank, warned that NHS/private partnerships would “hasten a two-tier health system”. He accused Hartley of displaying “astonishing naivete” in his attitude to “the for-profit sector, particularly those with private equity backers”. Such firms are only interested in the NHS so they can “use the highly trained NHS workforce to treat those patients who can afford to pay privately and jump the queue.

“The last Labour government thought that getting into bed with the private sector to finance, build and operate NHS hospitals under the PFI programme would bring in investment and expertise. In reality it has led to huge amounts of money leaking out of the NHS in the form of profits and has saddled NHS Trusts with massive, crippling debt repayments.

“The mistakes from this fiasco should not be repeated.”

General Election flashback to when voting was a privilege held by the few

In Plymouth, at the beginning of the 19th century, there were little more than two or three hundred ‘freemen’ who were empowered to vote.

Chris Robinson

4 JUL 2024

(Image: The Herald)

Up until the Reform Act of 1832, few people in this country could vote in parliamentary elections. In Plymouth, at the beginning of the 19th century, there were little more than two or three hundred ‘freemen’ who were empowered to vote.

The passing of the 1832 Act meant that virtually any man occupying a house worth £10 a year rent, whether freehold or leasehold, had the vote. There were great celebrations, however it still only meant that Plymouth had less than 1,500 voters out of a population of some 30,000 (one in 20).

Furthermore, it was to be another 34 years before voters could vote privately, by secret ballot, and in the meantime voting went on as it had long done, at public meetings like these, conducted outside the Theatre Royal.

Plymouth had been sending representatives to Parliament since at least 1298, but for over 500 years here, as elsewhere in the country, the right of election was in the hands of a very few men. Sometimes the matter was determined by the mayor and corporation on their own, sometimes by the freemen, either with or without the corporate body. There were four kinds of freemen; honorary, hereditary, apprenticed and purchased.

Prior to the Restoration, in 1660, there were very few honorary freemen; the hereditary title was passed on only to the eldest son and similarly the apprenticeship system tended only to apply to a freeman’s first apprentice. To purchase such an honour could cost anything from a few shillings to £25. Just before the 1832 Act was passed, a large number of these freedoms were purchased but they were to be of little use to the buyers – these new freemen had not voted prior to 1832 and, because they had not held the freedom for 12 months, the new Act extinguished them. The money raised was not handed back, it was put instead into the building of a new jail.

Hugh Fortescue was a figure of note in Plymouth politics in subsequent years. First elected in the Plymouth constituency as Viscount Ebrington in 1841, he was the son of the 2nd Earl Fortescue, who had first captured one of the Devon seats for the Reform cause back in 1818. Not that the nobility had that much difficulty finding seats, rotten boroughs (once populated areas where few people now lived and so there were few voters to win or buy over) and pocket boroughs (where voters were easily bought off) were to be found in all parts of the country.

Indeed, when the 2nd Earl Fortescue lost his Devon seat in 1820, the Duke of Bedford gave him the Tavistock seat that his own son, Lord John Russell, had just vacated.

Russell, a leading figure in the Reform movement, a future Prime Minister and grandfather of the philosopher Bertrand Russell, was first returned for the family borough of Tavistock in 1813, when he was just 21. In 1830, following the election occasioned by the death of George IV, Lord John was one of the four ministers entrusted with framing the first Reform Bill. It was ultimately his job to compose the document.

So it was that there was great disappointment among the Whigs and their many supporters when, in May 1832, it was learnt that the Reform Bill was being opposed in the House of Lords. In Plymouth, flags were put at half-mast and a meeting that drew 26,000 people from the Three Towns was held in the Bull Ring, under the Hoe (where the Belvedere was later constructed), all supporting the Bill. Great then were their celebrations when, on June 4, the Bill was finally passed.

In Plymouth, John Collier and Thomas Bewes, both ardent Reformers, were the first members to be sent up to Parliament. There was, however, no election on this occasion, as both were returned unopposed. Collier and Bewes then fought off two Tories in the election held after the accession of Queen Victoria in 1837, and four years later Thomas Gill and Viscount Ebrington held Plymouth for Liberals. In 1846, Ebrington was made a Lord of the Treasury and was obliged to stand again, and this time his only opposition was the Chartist, Henry Vincent, whom he defeated. In 1847, there were three candidates for the two seats, Ebrington (the 3rd Earl Fortescue), Roundell Palmer (Earl of Selborne), standing as a Liberal Conservative, and Charles Calmady.

Calmady was the chosen replacement for Gill and rather than go out and canvass, decided to trust ‘his admitted popularity’. The trust was misplaced and the Liberals lost a seat to the man who professed to be ‘free from all party engagements and opposed to all rash and fundamental changes’. The voting was Ebrington 921, Palmer 837 and Calmady 769. At the next election, in 1852, the Conservative candidate, Charles Mare, topped the poll, but he was subsequently unseated on a bribery charge.

Influence and intimidation still had its effect on elections, and it was not until the introduction of voting by ballot that unruly scenes outside the Theatre Royal came to an end. The last hustings were there were on November 30, 1868, for the South Devon elections, when Sir Massey Lopes was returned.

Which parties have UK newspapers endorsed for the general election?

On the eve of the general election, most major newspapers have now revealed who they will support.

Jimmy Nsubuga
Updated Wed, 3 July 2024

On the eve of the general election, most major newspapers have now revealed who they will support.

The Sun became one of the last major publications to declare its support for the vote on Thursday, backing Keir Starmer and the Labour Party by stating “It is time for a change."

Its front page alluded to the challenges faced by England manager Gareth Southgate at the Euros, with the headline: “As Britain goes to the polls, it’s time for a new manager (and we don’t mean sack Southgate!).”

This shift marks a departure for The Sun, which traditionally supported the Conservatives. It was perhaps noticeable that its front page did not feature an image of Starmer, and the accompanying editorial was limited in its praise, citing "plenty of concerns" about its approach to immigration.

Other publications which normally back the Tories, including the Sunday Times, Economist, and the Financial Times, have also urged UK voters to vote for Labour candidates.

The Guardian and the Mirror, which traditionally support Labour, have endorsed the party again.

However, the Sunday Telegraph and Sunday Express have remained loyal to the Tories by endorsing Rishi Sunak.

Here Yahoo News breaks down the endorsements from each major newspaper:

The Sun - Labour

The tabloid said it believes the Conservatives, over the past 14 years, have become a “divided rabble, more interested in fighting themselves than running the country”.

It said Labour leader Starmer has “fought hard” to change the party since the days of Jeremy Corbyn, adding it is “still a work in progress”.

The newspaper has a record of backing the party which then wins the most seats.

Evening Standard - Labour

The Evening Standard, which backed the Tories in the last four elections, endorsed the Labour Party.

It said: “Ultimately, after 14 years in office, the Tories have earned the right to lose. It is clear that this city wants change and that you have probably already made your mind up that Labour can be that change.”

The Guardian - Labour

The Guardian was dismissive of the past 14 years of governance, saying: "The Tories don’t deserve to win. After 14 years in power, they are a shambles. The original sin was austerity. But the precipitating crisis of this government was when voters were told that leaving the EU with the thinnest of deals would be good for them."

It says, instead, that: “Labour has climbed out of the crater of its 2019 defeat, and it stands on the brink of power with some eye-catching policies. On the environment, workers’ rights and housebuilding, it signals a break with the past, and a very welcome desire to save capitalism from its failures and excesses.”

Daily and Sunday Mirror - Labour

The Daily Mirror has backed Labour, saying “there are many reasons why we need Labour to win on July 4 but chief among them must be the chance to secure a better future for our children.”

The Sunday Mirror‘s endorsement of Labour dominated its front page on the weekend.

A collage of a range of its previous front pages featuring scandals from the Conservatives’ time in government sits beside a headline which says “14 years of Tory chaos”.

It also tells readers to “be on the right side of history this time” and to vote Labour.

The Independent - Labour

The Independent said: “Labour promises change and offers hope. In Rachel Reeves, Sir Keir will have a chancellor seen as sound on the economy, who promises to keep a steady hand on the wheel of the nation’s finances, after the wild lane-changing of the brief – but immensely damaging – tenure of Ms Truss and Mr Kwarteng. We hope their mantra will be to be compensatory and not too confiscatory.”

Financial Times - Labour

The Financial Times said in an editorial headlined "Britain needs a fresh start" that: "The FT still has concerns about Labour’s interventionist instincts and fervour for regulation. On many domestic questions, Labour’s answers fall short. Its manifesto too often tinkers around the edges."

Sunday Times - Labour

The Sunday Times stated at the weekend that the “Conservatives have in effect forfeited the right to govern”.

It said that Thursday is “a landmark” election after an “unedifying” campaign as voters pass judgment on 14 years of Conservative government.

Its editorial states “we cannot go on as we are, and we believe it is now the right time for Labour to be entrusted with restoring competence to government”.

Daily Record - Labour

The Daily Record said in a front page splash on 25 June: “This election is not about independence.

“It’s about poverty, spiralling mortgages, soaring bills, the cost of living crisis, a crashed economy, dodgy contracts, broken public services, a failed Brexit, Partygate. It’s about kicking this vile and corrupt Conservative government out of office.”

Observer - Labour

On its front page, the Observer stated that voters have the chance “not just to evict one of the worst governments this country has ever endured but to replace it with a Labour administration characterised by integrity and a respect for public office, an understanding of ordinary people’s lives, and an honest desire to make Britain a fairer and greener place”.

Economist - Labour

The Economist's endorsement of Labour is its first endorsement of the party since 2005. It said: "No party fully subscribes to the ideas that The Economist holds dear. If we had a vote on July 4th, we, too, would pick Labour, because it has the greatest chance of tackling the biggest problem that Britain faces: a chronic and debilitating lack of economic growth.

Mail on Sunday - Conservative

The Mail on Sunday comments: “It is not all over yet. Vote Conservative on Thursday and we may yet escape a long and punishing season of hard Labour.”

The Daily and Sunday Telegraph - Conservative

The Telegraph endorsed the Conservatives less than three hours after Sunak called the election.

It said: “The unarguable truth facing voters is that they face a straight choice between Sir Keir and Mr Sunak. It is similarly unarguable that a Labour government might well bring change, but it will not be of the good kind.

The Sunday Telegraph‘s editorial this weekend was headlined “Vote Tory to save Britain from Labour”.

It said: “Despite the unedifying nature of the campaign, this could come to be seen as one of the most consequential general elections in decades.

“It would be a disaster for Britain if Labour were to be given unparalleled power to refashion the country in its spiteful, intolerant, “progressive” image.

Sunday Express - Conservative

The Sunday Express told voters they are not only deciding if Britain needs change but also whether Starmer is allowed to deliver that change.

It added: “If you have any doubt he is the right person, the only sensible option is to vote Conservative.”

RED TORY

Sir Keir Starmer 'delighted' to receive backing of The Sun on day before polls open

The newspaper says while it supports many of Rishi Sunak's policies, the Conservatives are "exhausted" by 14 years in power and have become a "divided rabble".

Alexandra Rogers
Political reporter @Journoamrogers
Wednesday 3 July 2024

Keir Starmer. Pic: Reuters

Sir Keir Starmer has said he is "delighted" to receive the backing of The Sun after it endorsed him in the election.

The Labour leader said the newspaper's support for his leadership showed "just how much this is a changed Labour Party back in the service of working people".
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The Sun gave its backing to Sir Keir Starmer today - the day before polls open - on the grounds he had "won the right to take charge".

The newspaper said the Labour leader had "fought hard to change his party for the better, even if it still a work in progress".

It said while there were still "plenty of concerns about Labour", including a lack of a "clear plan" to tackle both legal and illegal immigration and concerns over tax rises, it was "time for change".

By contrast, The Sun said the Conservatives had become a "divided rabble, more interested in fighting themselves than running the country".

It said while Mr Sunak had "done his best to right the economic mess he inherited" and had put forward many "common sense" policies it supported, the Tories had become "exhausted" by their years in power.

"All this upheaval, backstabbing and mayhem came at a price," it said.

"The Tories allowed a work-from-home civil service 'blob', activist quangos and human rights lawyers and judges to run rings around them, thwarting sensible policies. Illegal and legal immigration have not been kept under control.

"Taxes have ballooned to the highest level since World War Two. Plotting against the leadership has been endless. Sleaze scandals - most recently gambling on the timing of the election - have broken public trust.

"Put bluntly, the Tories are exhausted.

"They need a period in opposition to unite around a common set of principles which can finally bring to an end all the years of internal warfare.

"It is time for a change."

The Sun coming out for a certain party has traditionally marked a decisive moment in general election campaigns.

In the 1992 general election, in which Sir John Major emerged victorious despite Labour hopes, The Sun boasted on its front page: "It's The Sun wot won it" and the mantra stuck.

Its backing of Sir Tony Blair in 1997 represented a pivotal moment for the Labour Party and his leadership, given its reputation as a staunch supporter of the Conservative Party.

While the Sun lacks the clout it did in 1997 - its readership has declined from nearly 4m daily copies then to approximately 1.2m now - its decision to offer a lukewarm endorsement of Sir Keir is telling given the differences it has with the Labour leader in certain policy areas, chiefly immigration.

The Sun's backing for Labour comes as the party continues to enjoy a commanding lead in the polls, with Survation predicting on Tuesday that Sir Keir's party would win a majority of 318 seats, surpassing the 179 achieved by Sir Tony Blair in 1997.

The pollster said Sir Keir would win 484 seats out of the total of 650, while the Tories would crash to 64 seats - just three more than the Liberal Democrats.

In its editorial, The Sun said it was "time for Labour" not just because of the state the Conservatives found themselves in but because of the remaining opposition parties.

It argued that Reform UK, despite having a manifesto that had "struck a chord with millions", was nevertheless a "one-man band" with little chance of taking power, while it branded the Liberal Democrats "a joke".

"Which means that it is time for Labour," it said.

"He [Sir Keir] has a mountain to climb, with a disillusioned electorate and low approval ratings.

"But, by dragging his party back to the centre ground of British politics for the first time since Tony Blair was in No10, Sir Keir has won the right to take charge."

CLIMATE CRISIS
Brazil’s Amazon sees worst 6 months of wildfires in 20 years

By AFP
July 1, 2024

Aerial view of a burnt area in the Amazon rainforest - Copyright AFP/File DOUGLAS MAGNO
Louis GENOT

The Brazilian Amazon recorded 13,489 wildfires in the first half of the year, the worst figure in 20 years, satellite data revealed Monday.

The total was up more than 61 percent compared to the same period last year — an increase that experts say is the result of a historic drought that struck the world’s largest tropical rainforest last year.

Since Brazil’s National Institute for Space Research (INPE) began compiling records in 1998, only two other years experienced more wildfires from January through June: 2003 (17,143) and 2004 (17,340).

The data makes for difficult news for the government of President Luiz Inacio Lula da Silva, with the number of fires increasing even as deforestation in the Amazon — which helps reduce global warming by absorbing carbon dioxide — is on the wane.

According to INPE data, the surface area subject to deforestation decreased 42 percent from January 1 to June 21, as compared with the same period in 2023.

Lula has pledged to put a stop to illegal deforestation of the Amazon by 2030. The practice had dramatically worsened under his far-right predecessor Jair Bolsonaro.

For Romulo Batista, the spokesman of the Brazilian branch of Greenpeace, “climate change is contributing” to the increase in the number of wildfires.

Batista explained to AFP that most of Brazil’s biomes, or distinct natural regions, are under stress due to a lack of precipitation.

“The environment is drier, and thus vegetation is more dried out and more vulnerable to fires,” he said.

But he said most of the wildfires were likely not spontaneous, such as being sparked by lightning, but instead caused by human activity — especially the use of agricultural burning.

– Record set in Pantanal wetlands-

Wildfires also set January-June records in two other biodiverse ecosystems south of the Amazon: the Pantanal, one of the world’s largest tropical wetlands, and the Cerrado savanna, which lies mainly in Brazil.

In the Pantanal, home to millions of caimans, parrots, giant otters and the world’s highest density of jaguars, 3,538 wildfires were recorded in the first six months of 2024 — an increase of more than 2,000 percent as compared with last year.

The total is also up 40 percent as compared with 2020, the record-setting year in that region.

In June alone, 2,639 fires were detected — six times the highest number ever recorded. In recent days, residents of the Pantanal have seen a red-tinged sky and clouds of smoke due to the blazes.

The situation is worrisome as the height of the wildfires season is normally in the second half of the year, especially in September, when weather is at its most dry.

Mato Grosso state, where much of the Pantanal is located, declared a state of emergency last week, and authorities announced that firefighters would be dispatched from other regions to help battle the flames.

The Cerrado — one of Earth’s three great savannas, along with Africa’s and Australia’s — experienced 13,229 fires from January through June, almost as many as the Amazon.

The Cerrado covers a region the size of France, Germany, Italy, Spain and Britain combined.

THE LAST COLONY VIVA INDPENDENCE

New Caledonia activist says he is ‘political prisoner’ in France

By AFP
July 1, 2024

CCAT spokesman Christian Tein said he was a 'political prisoner' - Copyright AFP/File DOUGLAS MAGNO

An indigenous Kanak pro-independence activist from the French Pacific territory of New Caledonia said Monday that he considered himself a “political prisoner” as authorities held him in jail in mainland France pending charges over a wave of deadly rioting.

Christophe Tein, 56, is leader of the CCAT pro-independence group, accused by Paris of orchestrating the weeks of unrest. The group’s members deny the accusation.

Tein spoke to two French Green party senators who visited him in isolation in jail in the northeastern French city of Mulhouse, in an exchange witnessed by AFP.

“I am a political prisoner and the first one to have been extradited in this way along with my comrades,” he said.

“I have been able to speak on the phone with my lawyer in Noumea but it is difficult because of the time difference. I have to make contact with a lawyer here,” he added.

Tein was one of seven pro-independence activists transferred to mainland France on July 23 from the territory, nearly 17,000 kilometres (10,600 miles) from Paris.

The move sparked a resurgence of rioting in New Caledonia.

Authorities have placed Tein under judicial investigation on suspicion of colluding in attempted murder and other charges.

The wave of rioting and looting erupted in New Caledonia in mid-May over a proposed electoral reform.

Kanak people fear the plan would leave them in a permanent minority compared with French from the mainland, putting independence hopes out of reach.

The violence has left nine dead and more than 1,500 people have been arrested, according to the High Commission that represents the French state in the territory.

Monday’s visit was supervised by authorities and Tein was not permitted to discuss his role in the unrest.

But he said that “At some point we will have to sit down to resume discussions. The survival of New Caledonia depends on it.”

The CCAT on Monday demanded the “immediate release and return” of the detained activists so they can be tried in New Caledonia, accusing French authorities of “colonial tactics”.

France’s Human Rights League said in a statement the activists’ detention on the faraway mainland was “a serious infringement of their right to private and family life”.

U.S. to help Panama deport migrants crossing Darién Gap

Jul 2, 2024

The U.S. will soon begin helping Panama deport migrants crossing the treacherous Darién Gap to reach the southern border. CBS News immigration and politics reporter Camilo Montoya-Galvez has details on the initiative.

Panama’s new president vows to end migrant ‘transit’

ByAFP
July 1, 2024

Panama's new President Jose Raul Mulino has vowed his country will no longer serve as a 'transit' point for US-bound undocumented migrants - Copyright AFP MARTIN BERNETTI

Jose Raul Mulino was sworn in Monday as Panama’s new president, with the right-leaning leader pledging to make his Central American country no longer a “transit” point for US-bound undocumented migrants.

Mulino, 65, was elected in May after a campaign in which he vowed to close the dangerous migration route through the Darien jungle between Colombia and Panama.

More than half a million undocumented migrants passed through the so-called Darien Gap last year — subject to abuses criticized by rights groups.

On Monday, after taking the oath of office, he said Panama “cannot continue to finance the economic cost of illegal migration… Panama will no longer be a transit country for illegal immigrants.”

He has previously promised to deport migrants bound for the United States who enter Panama illegally.

Following the ceremony, he signed an agreement with with President Joe Biden’s top border official, Alejandro Mayorkas, that pledges US funding for repatriating undocumented migrants from Panama.

“By returning such individuals to their country of origin, we will help deter irregular migration in the region and at our Southern border, and halt the enrichment of malign smuggling networks that prey on vulnerable migrants,” said US National Security Council spokeswoman Adrienne Watson in a statement.

The 165-mile (265-kilometer) Darien Gap has become a key corridor for migrants heading from South America through Central America and Mexico in hopes of reaching the United States and a chance at a better life.

They face dense jungle, treacherous terrain, wild animals and violent criminal gangs that extort, kidnap and abuse them.

Enough migrants traverse the Darien Gap that the Panamanian government has set up facilities and earmarked resources to aid them.

But Mulino, a conservative lawyer, pledged during his campaign that he would shut it down.

Colombian President Gustavo Petro, who attended the inauguration, also discussed the migration crisis with Mulino, according to an official report which gave no further details.

Mulino is the protege of popular former president Ricardo Martinelli, who could not run because he lost an appeal against a money-laundering conviction.

Among other challenges, Mulino also faces deep-rooted corruption, economic woes and a severe drought that has hobbled the economically critical Panama Canal.

SPACE

Europe’s Ariane 6 rocket finally ready for liftoff

By AFP
July 1, 2024

A dress rehearsal for the Ariane 6 rocket, which will launch for the first time on July 9 - Copyright ArianeGroup/AFP/File P. PIRON
Mathieu Rabechault

Europe’s new Ariane 6 rocket is set for its first-ever launch next week, carrying with it the continent’s hopes of regaining independent access to space and fending off soaring competition from Elon Musk’s SpaceX.

After four years of delays, the European Space Agency’s (ESA) most powerful rocket yet is finally due to blast off from Europe’s spaceport in Kourou, French Guiana, at 3:00 pm (1800 GMT) on July 9.

Since the last flight of the rocket’s workhorse predecessor, Ariane 5, a year ago, Europe has been unable to launch satellites or other missions into space without relying on rivals such as the US firm SpaceX.

Kourou was the site of launches by Russia’s Soyuz rockets for more than a decade, before Moscow withdrew them after invading Ukraine in 2022.

Later that year, Europe’s Vega-C light launcher was grounded after a launch failure. Delays to Ariane 6’s first flight — originally scheduled for 2020 — compounded the crisis.

“Everything that could go wrong went wrong,” ESA chief Josef Aschbacher said.

That is why “Ariane 6 is crucial for Europe,” he added. “It’s absolutely mandatory for Europe to have an independent access to space.”

After the struggles of the 4.5-billion-euro ($4.8 billion) programme, Europe’s space industry has been nervously observing the run-up to the launch.

A “wet dress rehearsal” late last month ran through all the launch procedures, right up to the moment before the engines ignite on the launchpad.

It went “very smoothly… like a Swiss watch,” ESA space transportation acting director Toni Tolker-Nielsen said, adding that there was nothing to call the launch date into question.

– ‘Important moment’ –

Ariane 6 will put satellites into geostationary orbit, which appears stationary by matching Earth’s speed at 36,000 kilometres (22,000 miles) above Earth. It can also launch constellations a few hundred kilometres up.

The rocket’s upper stage, powered by the Vinci engine, ignites after take-off to place satellites in orbit before falling into the Pacific Ocean — a special feature to prevent space debris.

Ariane 6’s first launch will use two boosters, with a more powerful four-booster version scheduled for liftoff in the middle of next year.

However, the boosters and other parts of the rocket are not reusable — unlike SpaceX’s Falcon 9 rocket.

Billionaire Musk has repeatedly criticised Ariane 6 for not being reusable.

The European response has been that it would not make economic sense for the rocket to be reusable because it was designed for far fewer launches than the Falcon 9.

The rocket will initially carry out nine launches a year — a far cry from the Falcon 9, which managed 14 in May alone.

The rocket’s inaugural flight will carry 18 different smaller items, including university micro-satellites and scientific experiments.

Its first commercial flight is scheduled for later in 2024, with 14 more planned over the next two years.

– Shock late cancellation –

One positive for Ariane 6 is that space business is booming.

The amount spent on launchers, satellites and other parts of the space economy is projected to surge to $822 billion by 2032, up from $508 billion last year, according to consulting firm Novaspace.

But this has not yet been enough to make Ariane 6 profitable.

The financing for the first 15 launches has been secured.

But the ESA’s 22 member states have agreed to subsidise the rocket for up to 340 million euros a year from its 16th to 42nd flights — in return for an 11 percent discount.

Ariane 6 already has an order book of 30 missions, including 18 to deploy some of Amazon’s Kuiper constellation of internet satellites.

“That is absolutely unprecedented for a rocket that has not flown,” said Stephane Israel, CEO of launch service provider Arianespace.

However, just days before the inaugural flight, Europe’s weather satellite operator EUMETSAT cancelled plans to use the European Ariane 6 in favour of SpaceX’s Falcon 9, citing “exceptional circumstances”.

Philippe Baptiste, head of France’s CNES space agency, called it “a very disappointing day for European space efforts”.

Faced with such stiff competition, the challenge for Ariane 6 will be to survive in a “market that needs rockets”, ArianeGroup CEO Martin Sion said.

After all, Ariane 6 is “Europe’s sovereignty launcher”, he added.

Moon ‘swirls’ could be magnetized by unseen magmas

Mysterious, light-colored swirls on Moon’s surface could be rocks magnetized by magma activity underground, WashU laboratory experiments confirm

WASHINGTON UNIVERSITY IN ST. LOUIS

Lunar swirls are light-colored, sinuous features on the Moon’s surface, bright enough to be visible from a backyard telescope. Some people think they look like the brushstrokes in an abstract painting. But these are not mere artistic flourishes: NASA images show that the tendrils from some lunar swirls extend for hundreds of miles.

Lunar swirls have defied easy explanation, but recent modeling and spacecraft data shed light on the twisty mystery. The data shows that rocks in the swirls are magnetized, and these rocks deflect or redirect solar wind particles that constantly bombard the Moon. Nearby rocks take the hit instead. Over time, neighboring rocks become darkened by chemical reactions caused by the collisions, while the swirls remain light colored.

But how did the rocks in lunar swirls get magnetized? The Moon does not have a magnetic field today. No astronaut or rover has yet visited a lunar swirl to investigate.

“Impacts could cause these types of magnetic anomalies,” said Michael J. Krawczynski, an associate professor of earth, environmental and planetary sciences in Arts & Sciences at Washington University in St. Louis. He notes that meteorites regularly deliver iron-rich material to areas on the Moon’s surface. “But there are some swirls where we’re just not sure how an impact could create that shape and that size of thing.”

Krawczynski believes it’s more likely that something else has locally magnetized the swirls.

“Another theory is that you have lavas underground, cooling slowly in a magnetic field and creating the magnetic anomaly,” said Krawczynski, who designed experiments to test this explanation. His results are published in the Journal of Geophysical Research: Planets.

Krawczynski and study first author Yuanyuan Liang, who recently earned her PhD in earth, environmental and planetary sciences in Arts & Sciences, measured the effects of different combinations of atmospheric chemistry and magmatic cooling rates on a mineral called ilmenite to see if they could produce a magnetizing effect.

“Earth rocks are very easily magnetized because they often have tiny bits of magnetite in them, which is a magnetic mineral,” Krawczynski said. “A lot of the terrestrial studies that have focused on things with magnetite are not applicable to the Moon, where you don’t have this hyper-magnetic mineral.”

But ilmenite, which is abundant on the Moon, can also react and form particles of iron metal, which can be magnetized under the right conditions, Krawczynski and his team found.

“The smaller grains that we were working with seemed to create stronger magnetic fields because the surface area to volume ratio is larger for the smaller grains compared to the larger grains,” Liang said. “With more exposed surface area, it is easier for the smaller grains to undergo the reduction reaction.”

“Our analog experiments showed that at lunar conditions, we could create the magnetizable material that we needed. So, it’s plausible that these swirls are caused by subsurface magma,” said Krawczynski, who is a faculty fellow in the university’s McDonnell Center for the Space Sciences.

Determining the origin of lunar swirls is considered key in understanding what processes have shaped the lunar surface, the history of a magnetic field on the Moon and even how the surfaces of planets and moons generally affect the space environment surrounding them.

This study will help interpret data acquired by future missions to the Moon, especially those that explore magnetic anomalies on the lunar surface. NASA intends to send a rover to the lunar swirl area known as Reiner Gamma in 2025 as part of the Lunar Vertex mission.

“If you’re going to make magnetic anomalies by the methods that we describe, then the underground magma needs to have high titanium,” Krawczynski said. “We have seen hints of this reaction creating iron metal in lunar meteorites and in lunar samples from Apollo. But all of those samples are surface lava flows, and our study shows cooling underground should significantly enhance these metal-forming reactions.”

For now, his experimental approach is the best way to test predictions about how unseen lava may be driving the magnetic effects of the mysterious lunar swirls.

“If we could just drill down, we could see if this reaction was happening,” Krawczynski said. “That would be great, but it’s not possible yet. Right now, we’re stuck with the surface.”

JOURNAL

Journal of Geophysical Research Planets

DOI

10.1029/2023JE008179

Russia to build new orbital station by 2033

Yury Borisov, head of Russia's state space corporation Roscosmos, has approved the schedule for the creation of a Russian orbital station by 2033, the corporation said in a press release Tuesday.

The schedule includes the design and construction of the space modules, flight tests of a new-generation manned spaceship, the creation of launch vehicles and space infrastructure on Earth, and a timetable for the work of scientific institutes supporting the project, the statement said.

The document was also signed by the general directors of 19 enterprises which are involved in the construction of the new orbital station.

The scientific and energy module will be launched first in 2027, and three other core modules, namely the universal nodal, gateway and base modules, will be launched by 2030. Two other target modules are scheduled to be launched by 2033.

A total of 608.9 billion rubles (around 6.9 billion U.S. dollars) has been allocated to finance the project, Roscosmos said.

The corporation further said the creation of the Russian orbital station would ensure the continuity of Russia's space program and address issues of national security and scientific and technological development. The station would also serve as a platform for testing space technologies, it noted.

Machine learning could aid efforts to answer long-standing astrophysical questions

DOE/PRINCETON PLASMA PHYSICS LABORATORY

Plasmoids — IMAGE:
AN ARTIST'S REPRESENTATION OF PLASMOID DETECTION USING MACHINE LEARNING
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CREDIT: KYLE PALMER / PPPL COMMUNICATIONS DEPARTMENT

In an ongoing game of cosmic hide and seek, scientists have a new tool that may give them an edge. Physicists at the U.S. Department of Energy’s (DOE) Princeton Plasma Physics Laboratory (PPPL) have developed a computer program incorporating machine learning that could help identify blobs of plasma in outer space known as plasmoids. In a novel twist, the program has been trained using simulated data.

The program will sift through reams of data gathered by spacecraft in the magnetosphere, the region of outer space strongly affected by Earth’s magnetic field, and flag telltale signs of the elusive blobs. Using this technique, scientists hope to learn more about the processes governing magnetic reconnection, a process that occurs in the magnetosphere and throughout the universe that can damage communications satellites and the electrical grid.

Scientists believe that machine learning could improve plasmoid-finding capability, aid the basic understanding of magnetic reconnection and allow researchers to better prepare for the aftermath of reconnection-caused disturbances.

“As far as we know, this is the first time that anyone has used artificial intelligence trained on simulated data to look for plasmoids,” said Kendra Bergstedt, a graduate student in the Princeton Program in Plasma Physics, which is based at PPPL. Bergstedt was the first author of the paper reporting the results in Earth and Space Science. The work pairs the Lab’s growing expertise in computational sciences with its long history of exploring magnetic reconnection.

Looking for a link

Scientists want to find reliable, accurate methods for detecting plasmoids so they can determine whether they affect magnetic reconnection, a process consisting of magnetic field lines separating, violently reattaching and releasing tremendous amounts of energy. When it occurs near Earth, reconnection can trigger a cascade of charged particles falling into the atmosphere, disrupting satellites, mobile phones and the electrical grid. “Some researchers believe that plasmoids aid fast reconnection in large plasmas,” said Hantao Ji, professor of astrophysical sciences at Princeton University and a distinguished research fellow at PPPL. “But those hypotheses haven’t been proven yet.”

The researchers want to know whether plasmoids can change the rate at which reconnection occurs. They also want to gauge how much energy reconnection imparts to the plasma particles. “But to clarify the relationship between plasmoids and reconnection, we have to know where the plasmoids are,” Bergstedt said. “That’s what machine learning could help us do.”

The scientists used computer-generated training data to ensure the program could recognize a range of plasma signatures. Typically, plasmoids created by computer models are idealized versions based on mathematical formulas with shapes — like perfect circles — that do not often occur in nature. If the program were trained only to recognize these perfect versions, it might miss those with other shapes. To prevent those misses, Bergstedt and Ji decided to use artificial, deliberately imperfect data so the program would have an accurate baseline for future studies. “Compared to mathematical models, the real world is messy,” Bergstedt said. “So we decided to let our program learn using data with fluctuations that you would get in actual observations. For instance, rather than beginning our simulations with a perfectly flat electrical current sheet, we give our sheet some wobbles. We’re hoping that the machine learning approach can allow for more nuance than a strict mathematical model can.” This research builds on past attempts in which Bergstedt and Ji wrote computer programs that incorporated more idealized models of plasmoids.

The use of machine learning will only become more common in astrophysics research, according to the scientists. “It could particularly be helpful when making extrapolations from small numbers of measurements, as we sometimes do when studying reconnection,” said Ji. “And the best way to learn how to use a new tool is to actually use it. We don’t want to stand on the sidelines and miss an opportunity.”

Bergstedt and Ji plan to use the plasmoid-detecting program to examine data being gathered by NASA’s Magnetospheric Multiscale (MMS) mission. Launched in 2015 to study reconnection, MMS consists of four spacecraft flying in formation through plasma in the magnetotail, the area in space pointing away from the sun that is controlled by Earth’s magnetic field.

The magnetotail is an ideal place to study reconnection because it combines accessibility with scale. “If we study reconnection by observing the sun, we can only take measurements from afar,” Bergstedt said. “If we observe reconnection in a laboratory, we can put our instruments directly into the plasma, but the sizes of the plasmas would be smaller than those typically found in space.” Studying reconnection in the magnetotail is an ideal middle option. “It’s a large and naturally occurring plasma that we can measure directly using spacecraft that fly through it,” Bergstedt said.

As Bergstedt and Ji improve the plasmoid-detecting program, they hope to take two significant steps. The first is performing a procedure known as domain adaptation, which will help the program analyze datasets that it has never encountered before. The second step involves using the program to analyze data from the MMS spacecraft. “The methodology we demonstrated is mostly a proof of concept since we haven’t aggressively optimized it,” Bergstedt said. “We want to get the model working even better than it is now, start applying it to real data and then we’ll just go from there!”

This research was supported by the DOE’s Fusion Energy Sciences program under contract DE-AC0209CH11466, by NASA under grants NNH15AB29I and 80HQTR21T0105, and by the National Science Foundation Graduate Research Fellowship under grant DGE-2039656.

PPPL is mastering the art of using plasma — the fourth state of matter — to solve some of the world's toughest science and technology challenges. Nestled on Princeton University’s Forrestal Campus in Plainsboro, New Jersey, our research ignites innovation in a range of applications, including fusion energy, nanoscale fabrication, quantum materials and devices, and sustainability science. The University manages the Laboratory for the U.S. Department of Energy’s Office of Science, which is the nation’s single largest supporter of basic research in the physical sciences. Feel the heat at https://energy.gov/science and http://www.pppl.gov.

JOURNAL

Earth and Space Science

DOI

10.1029/2023EA002965

ARTICLE TITLE

A Novel Method to Train Classification Models for Structure Detection in In Situ Spacecraft Data

lmpact flux on the Moon

BEIJING INSTITUTE OF TECHNOLOGY PRESS CO., LTD

Fig. 1. Locations of samples returned from the Moon. Model ages of mare deposits [1] were based on superposed crater densities and the Neukum crater chronology [23]. The Moon had a much higher impact flux before the visible lunar mare were emplaced, but t — IMAGE:
FIG. 1. LOCATIONS OF SAMPLES RETURNED FROM THE MOON. MODEL AGES OF MARE DEPOSITS [1] WERE BASED ON SUPERPOSED CRATER DENSITIES AND THE NEUKUM CRATER CHRONOLOGY [23]. THE MOON HAD A MUCH HIGHER IMPACT FLUX BEFORE THE VISIBLE LUNAR MARE WERE EMPLACED, BUT THE EARLY IMPACT HISTORY IS LARGELY UNCONFIRMED. FORMATION AGES OF SEVERAL CRITICAL IMPACT BASINS SUCH AS THOSE ANNOTATED IN THE FIGURE ARE CRITICAL TO EVALUATE THE EARLY IMPACT FLUX [56]. THE BASE IMAGE IS A SHADED RELIEF MODEL (VERTICAL EXAGGERATION OF 8) BASED ON THE GLOBAL DIGITAL ELEVATION MODEL CONSTRUCTED USING LUNAR ORBITER LASER ALTIMETER DATA.
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CREDIT: SPACE: SCIENCE & TECHNOLOGY

Firstly, the scholars reviewed the existing anchor points and construction history of lunar crater chronology. Before the return of lunar samples, the stratification of the near side of the Moon was based on remote sensing data from ground-based telescopes and lunar orbiters. As shown in Fig. 1, six manned missions and four robotic missions have so far brought back samples, including basalts and volcanic glass, from different geological units of the Moon. Based on the lithology and thermal history of these samples, radiometric dating techniques have determined their radiometric ages, which are then used to interpret the exposure ages of geological units. However, geological background investigations of lunar samples revealed uncertainties due to unclear sample origins and difficulties in deriving crater groups. The mixed nature of the regolith makes the geological relationship between samples and specific geological units unclear. Impact craters play a crucial role in estimating the model ages of geological units on the Moon and other solid bodies in the solar system. Scholars typically fit mathematical functions to establish lunar crater chronology functions, which predict the model ages of geological units on the Moon and other solid solar system bodies. These predictions are validated by samples returned from deep space exploration missions. For example, samples returned by the Chang'e-5 mission further validated the reliability of age determination techniques based on crater statistics, thereby supporting the current popular lunar crater chronology model.

The article then introduced the main consensus and findings regarding lunar impact flux. Firstly, the lunar impact record began during the solidification phase of the lunar magma ocean. Early impacts did not leave clear records due to the continuous differentiation of the magma ocean. After the magma ocean had mostly solidified around 4.46 billion years ago, the lunar impact structures started to be preserved. Secondly, the unexpectedly high content of highly siderophile elements (HSEs) in the lunar mantle suggests that the Moon continued to be bombarded by chondritic meteorites after the differentiation of the magma ocean, possibly due to a late veneer impact event. Thirdly, the comparison of crater densities between the lunar highlands and maria indicates that the Moon experienced a late heavy bombardment event, with the impact flux significantly higher around 3.8 billion years ago compared to later periods. The South Pole-Aitken (SPA) basin, believed to be one of the largest impact structures on the Moon, possibly formed around 4.3 billion years ago. This was followed by the late heavy bombardment (LHB) period around 3.8 billion years ago, which led to significant geological and biochemical evolution on the Moon and terrestrial planets. Lastly, since around 3.8 billion years ago, the lunar impact flux has remained relatively stable, with occasional peaks but no significant changes in overall stability. These findings are crucial for understanding the evolution of the Moon and terrestrial planets.

Then, the article introduced the main disagreements and significant progress in resolving the controversy surrounding the impact flux around 3.8 billion years ago. The primary uncertainty in lunar impact flux arises from the mismatch between radiometric ages and model ages predicted by crater chronology. This uncertainty mainly stems from the imperfect calibration of radiometric ages and crater production statistical data, which is common for geological units older than approximately 3.92 billion years, with diameters greater than 300 kilometers or less than about 10 meters. Additionally, there are other issues such as the precise isotopic ages of returned samples not clearly indicating their source; the unclear origins of early lunar impact events and orbital dynamics; the possibility that the late veneer may have formed after the solidification of the lunar magma ocean, but its specific origin remains uncertain; early lunar impact history providing constraints on the final stages of planetary formation, potentially related to the orbital dynamics of the entire solar system; the uncertain relationship between the lunar late mantle and late heavy bombardment events, making it difficult to attribute early geophysical and geochemical characteristics to specific geological contexts. As shown in Fig. 5, the crater groups in the lunar highlands resemble modern main-belt asteroid impactors, suggesting that the main asteroid belt could have been the primary source for impacts on the Moon before 3.8 billion years ago. However, the source and dynamics of early impactors remain uncertain and require further research to resolve these issues.

Finally, the authors summarized the current research and discussed future research directions in the context of planned sample returns. While techniques such as sample analysis, high-resolution geological mapping, geophysical surveys, and orbital dynamics modeling can reduce uncertainties related to unclear sample origins and challenges in deriving crater groups, they have not fundamentally addressed the weak understanding of early meteorite impact processes. Currently, calibrating lunar impact flux based on sample and crater structure remains elusive. However, in the coming years, with upcoming lunar exploration missions from various countries set to return more samples and remote sensing data, future research will prioritize sampling sites older than 3.92 billion years. This approach aims to connect planetary evolution and orbital dynamics, resolve early impact history, and further enhance understanding of lunar impact flux. By designing new exploration missions and research strategies, advancements are expected in calibrating lunar impact flux and elucidating early meteorite impact processes.

Fig. 5. Similar sources of impactors of inner Solar System bodies, but different crater populations and impactors before and after ~3.8 Ga. This figure is adapted from Strom et al. [12]. (A) SFD of crater populations formed on terrains older and younger than 3.8 Ga on the Moon and terrestrial planets. (B) SFD of impactors that formed the crater population in the lunar highland (red circles) and that in the Mars northern plains (green open circle). The older impactor population is comparable with the current main belt asteroids, and the younger impactor population is comparable with the near-Earth asteroids (NEAs). Subaru, SDSS, Spacewatch, IRAS, and LINEAR are telescopes for asteroid observations [12,13].

JOURNAL

Space: Science & Technology