NASA has successfully smashed a spacecraft into an asteroid seven million miles from Earth.
The last image from the “vending machine-sized” collider showed the surface of the asteroid Dimorphos seconds before impact.
The Double Asteroid Redirection Test (DART) is the first-ever trial of a “planetary defence system”.
If the orbit of an asteroid can be changed by an object sent into space, humanity may have a chance at protecting itself from the kind of disaster that did it for the dinosaurs.
NASA, and the international team of astronomers working with them, chose their target carefully. To prove success, they needed an asteroid they can carefully monitor following the collision. They also needed to make sure any impact wouldn’t send a previously harmless piece of rock spiralling towards Earth.
They picked a pair of asteroids: the 780 metre-wide Didymos, and its moon Dimorphos which is 160m wide – about the size of the Great Pyramid.
Image: DART approaches Dimorphos
Because Dimorphos is already safely orbiting its bigger partner, they can study the change in its behaviour following the collision.
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Dimorphos is also a fairly common size of asteroid. While significantly smaller than a kilometres-wide “planet killer”, it’s of a type easily big enough to destroy a city.
“What Dart is going up there to prove is that we actually do have a system for kinetic deflection, nudging these away and nudging them off course,” says Betsy Congdon, DART’s mechanical systems engineer at Johns Hopkins University in Maryland.
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If you’ve seen Hollywood disaster movies Deep Impact, Armageddon or more recently Don’t Look Up, prepare yourself for mild disappointment.
Despite smashing a half-tonne spacecraft into Dimorphos at close to 15,000 miles an hour, the effect on the asteroid is expected to be tiny – checking its speed by just 0.4mm per second.
But over time, that should have a measurable effect on its orbit. An array of land and space-based telescopes including NASA and ESA’s new James Webb Space Telescope, will all study the asteroid to measure the outcome of the test.
Image: An illustration of NASA’s DART spacecraft on a collision course with the asteroid Dimorphos. Pic: NASA/Johns Hopkins APL
Although it’s only a modest objective, the engineering involved was a major undertaking. Didymos is far too small and far away for DART to be steered into it from Earth. The probe had to use an autonomous guidance system to target the asteroid which is so small it was only visible in DART’s cameras about 50 minutes before impact. But the sat-nav seems to have worked perfectly.
The hope is, that a tiny nudge might be enough – if the impact is sufficiently far away – to deflect a future asteroid on collision course with Earth off target.
Astronomers estimate they have tracked the orbits of 95% of asteroids large enough to destroy life on Earth and none is currently on a collision course. But there are many smaller ones. According to NASA, no known asteroid larger than 140m across is likely to hit Earth in the next 100 years. But they think they’ve only found about 40% of them.
Image: The NASA team celebrates as DART impacts Dimorphos
Around 66 million years ago a 10km-wide asteroid slammed into what is now the Yucatan Peninsular of Mexico. It left a crater 110 miles wide and 12 miles deep. The resulting change in the planet’s climate is thought to have caused the Cretaceous-Paleogene extinction event. The impact wiped out 75% of animal and plant species on Earth – and famously ended the reign of flightless dinosaurs.
But even small space rocks can lead to a bad day on Earth. In 2013 a 20m-wide asteroid exploded as a meteorite over the city of Chelyabinsk in the Ural region of Russia. The blast was equivalent to 500 tonnes of TNT, about a third of the force of the Hiroshima bomb. While no deaths were reported there were more than 1,400 casualties, some of them serious.
“An asteroid impact is the one kind of natural disaster that we could potentially see coming decades away,” says Prof Colin Snodgrass at the University of Edinburgh is a member of the DART team.
He’s helped set up a telescope in Kenya to monitor the impact from Earth. “If one [the size of Dimorphos] was ever discovered coming towards earth being able to do something about that seems like a very sensible technology to have.”
In years to come, it may become known simply as Chequers ’25.
But today’s summit between Sir Keir Starmer and Donald Trump, at the prime minister’s country retreat, has the potential to be a landmark moment in UK-US history.
There’s plenty of scope for it to go horribly wrong, of course: over Jeffrey Epstein, Sir Keir’s pledge to recognise Palestine, the president’s lukewarm support for Ukraine, the Chagos Islands sell-off, or free speech.
But on the other hand, it could be a triumph for the so-called “special relationship” – as well as relations between these two unlikely allies – with deals on trade and tariffs and an improbably blossoming bromance.
Either way, this Chequers summit – on the president’s historic second state visit to the UK – could turn out to be one of the most notable one-to-one meetings between PM and president in 20th and 21st century history.
Image: Donald Trump and Keir Starmer wave as they board Air Force One on a previous trip. Pic: AP
It was then that the PM theatrically pulled King Charles’s invitation for this week’s visit out of his inside pocket in a spectacular stunt surely masterminded by the “Prince of Darkness”, spin doctor-turned-ambassador (until last week, anyway) Peter Mandelson.
And over the years, there have been some remarkable and historic meetings and relationships, good and bad, between UK prime ministers and American presidents.
From Churchill and Roosevelt to Eden and Eisenhower, from Macmillan and JFK to Wilson and Johnson, from Thatcher and Reagan, to Blair and Bush, and from Cameron and Obama… to Starmer and Trump, perhaps?
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4:08
‘History’ that binds the UK and US
A brief history of relationships between PMs and presidents
Throughout UK-US history, there have been many examples of a good relationship and close bond between a Labour prime minister and a Republican president. And vice versa.
Also, it has not always been rosy between prime ministers and presidents of the two sister parties. There have been big fallings out: over Suez, Vietnam and the Caribbean island of Grenada.
Leading up to this Chequers summit, the omens have not been good.
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3:47
Trump meets Starmer: What can we expect?
Second, the president arrived in the UK to a barrage of criticism from London mayor Sir Sadiq Khan, who accused him of doing more than anyone else to encourage the intolerant far right across the globe.
Image: Churchill and FDR at the White House in 1941. Pic: AP
Back in the mid-20th century, the godfather of the “special relationship” was wartime leader Sir Winston Churchill, though it was 1946 before he first coined the phrase in a speech in the US, in which he also spoke of the “iron curtain”.
It was in 1941 that Churchill held one of the most significant meetings with a US president, Franklin D Roosevelt, at a Washington conference to plot the defeat of Germany after Japan’s attack on Pearl Harbour.
Churchill arrived in Washington in December after a rough 10-day voyage on a Royal Navy battleship and stayed three weeks, spending Christmas in the White House and on Boxing Day becoming the first UK PM to address Congress.
The close bond between Churchill and Roosevelt was described as a friendship that saved the world. It was even claimed one reason the pair got on famously was that they were both renowned cigar smokers.
Churchill and Truman
Image: Churchill and Truman catch a train from Washington in 1946. Pic: AP
After the war ended, Churchill’s “special relationship” speech, describing the alliance between the UK and US, was delivered at Westminster College, in Fulton, Missouri in March 1946.
The speech was introduced by president Harry Truman, a Democrat, with whom Churchill had attended the Potsdam Conference in 1945 to negotiate the terms of ending the war.
These two were also close friends and would write handwritten letters to each other and address one another as Harry and Winston. Mr Truman was also the only US president to visit Churchill at Chartwell, his family home.
Eden and Eisenhower
Image: Eden and Eisenhower shake hands at the conclusion of their three-day conference in 1956. Pic: AP
But the transatlantic cosiness came to an abrupt end in the 1950s, when Churchill’s Conservative successor Anthony Eden fell out badly with the Republican president Dwight Eisenhower over the Suez Crisis.
Mr Eden did visit Mr Eisenhower in Washington in January 1956, and the official record of the meeting describes the discussion as focussing on “policy differences and Cold War problems”.
Macmillan and JFK
Image: Harold Macmillan and John F Kennedy at Andrews Air Force Base. Pic: AP
But in the early 1960s, a Conservative prime minister and a Democrat president with seemingly nothing in common, the stuffy and diffident Harold Macmillan, and the charismatic John F Kennedy, repaired the damage.
They were credited with rescuing the special relationship after the rupture of the Suez Crisis, at a time of high tensions around the world: the Berlin Wall, the Cuban missile crisis, and the threat of nuclear weapons.
The two leaders exchanged handwritten notes, as well as Christmas and birthday cards. The Macmillans visited the Kennedys twice at the White House, in 1961 and 1962 – the second described in the US as a “momentous” meeting on the Cuban crisis.
The relationship was abruptly cut short in 1963 by Supermac’s demise prompted by the Profumo scandal, and JFK’s assassination in Dallas. But after her husband’s death, Jacqueline Kennedy was said to have had a father-daughter relationship with Macmillan, who was said to have been enchanted with her.
Wilson and LBJ
Image: Johnson meeting with Wilson. Pic: Glasshouse Images/Shutterstock
After JFK, the so-called special relationship cooled once again – and under a Labour prime minister and Democrat president – when Harold Wilson rejected pressure from Lyndon B Johnson to send British troops to Vietnam.
Mr Wilson became prime minister in 1964, just two months after LBJ sent US troops. His first overseas trip was to the White House, in December 1964, and the PM returned to tell his cabinet: “Lyndon Johnson is begging me even to send a bagpipe band to Vietnam.”
Thatcher and Reagan
Image: Thatcher at Reagan’s 83rd birthday celebrations. Pic: Reuters
And even though Margaret Thatcher and Ronald Reagan were ideological soulmates, Thatcher was furious when she wasn’t consulted before the Americans invaded Grenada in 1983 to topple a Marxist regime.
Even worse, according to Mrs Thatcher’s allies, a year earlier, Reagan had stayed neutral during the Falklands War. Reagan said he couldn’t understand why two US allies were arguing over “that little ice-cold bunch of land down there”.
Image: Thatcher and Reagan became firm friends. Pic: Reuters
But their relationship didn’t just survive, it flourished, including at one memorable visit to the presidential retreat at Camp David in 1984, where Reagan famously drove Mrs T around in a golf buggy.
They would also memorably dance together at White House balls.
Blair and Bush
Image: Blair hosts Bush in Durham in 2003. Pic: PA
Camp David was also where, in 2001, Republican president George W Bush and Labour’s Sir Tony Blair embarked on the defining mission of his premiership: the Iraq War. It was to prove to be an historic encounter.
The war was the turning point of Sir Tony’s decade in Number 10. He was branded a liar over claims about Saddam Hussein’s “weapons of mass destruction”, he was vilified by the Labour left, and it was the beginning of the end for him.
And to add to the suspicion among Sir Tony’s critics that he was Mr Bush’s poodle, in 2006 at a G8 summit in St Petersburg – that wouldn’t happen now – a rogue microphone picked up the president calling, “Yo, Blair! How are you doing?”
Cameron and Obama
Image: Cameron and Obama serve food at a barbecue in the garden of 10 Downing Street. Pic: Reuters
Some years later, the Tory prime minister sometimes called the “heir to Blair”, David Cameron, bonded over burgers with the Democrat president Barack Obama, serving a BBQ lunch to military families in the Downing Street garden. They also played golf at the exclusive Grove resort in 2016.
They seemed unlikely allies: Obama, the first African-American president, and Cameron, the 19th old Etonian prime minister. It was claimed they had a “transatlantic bromance” in office. “Yes, he sometimes calls me bro,” Lord Cameron admitted.
But not everything went well.
The Tory PM persuaded Mr Obama to help the Remain campaign in the 2016 Brexit referendum, when he claimed the UK would be “at the back of the queue” on trade deals with the US, if it left the EU. It backfired, of course.
Now it’s Sir Keir Starmer’s turn to tread a delicate and potentially hazardous political tightrope as he entertains the latest – and most unconventional – US president.
The greatest dangers for Sir Keir will be a news conference in the afternoon, in the gardens, if the weather permits.
Good luck, as they say, with that.
Before then, there’s the potential for what the Americans call a “pool spray”, one of those impromptu, rambling and unpredictable Q&As we’ve seen so many times in the Oval Office.
For Sir Keir, what could possibly go wrong?
Chequers ’25 could be memorable and notable, like so many previous meetings between a PM and a president. But not necessarily for the right reasons for this UK prime minister.
The pomp and circumstance. The man who some say wants to be king, meets The King.
Trump and King Charles spend the day together. We digest what’s happened, why it’s happened, and what it all means. You can also watch all episodes on our YouTube channel.
Email us on trump100@sky.uk with your comments and questions.
The comedian told his audience “many in MAGA land are working very hard to capitalise on the murder of Charlie Kirk”.
He added the president’s response to Mr Kirk’s death “is not how an adult grieves the murder of someone he called a friend”.
Disney-owned ABC said it would be taken off-air indefinitely – and with immediate effect – after network operator Nexstar said it would stop broadcasting the programme.
Andrew Alford, president of Nexstar’s broadcasting division, said it “strongly objects” to Kimmel’s comments.
“Mr Kimmel’s comments about the death of Mr Kirk are offensive and insensitive at a critical time in our national political discourse,” he said, with the show to go off-air to “let cooler heads prevail”.
Mr Trump welcomed the news on Truth Social, writing “congratulations to ABC” and “Kimmel has ZERO talent”.
But Kimmel’s suspension has triggered outrage from Democrats like California Governor Gavin Newsom, who posted on X: “The @GOP [Republican Party] does not believe in free speech. They are censoring you in real time.”
Senate minority leader Chuck Schumer called for people “across the political spectrum… to stop what’s happening to Jimmy Kimmel”.
What happened?
Kimmel called out what he believes is hypocrisy in how Republicans have responded to Mr Kirk’s death.
In a separate Truth Social post in the early hours of Thursday, the president – who is in the UK for his state visit – announced the anti-fascist Antifa movement would be designated as a terrorist organisation.
Mr Kirk’s suspected killer, Tyler Robinson, appeared in court for the first time on Tuesday. Prosecutors said he had shared negative views about Mr Kirk, an influential media figure in the MAGA movement.
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11:54
The killing of Charlie Kirk
On the Monday edition of his show, Kimmel drew attention to Capitol rioters who “wanted to hang” Mr Trump’s first term vice president, Mike Pence, for certifying Joe Biden’s 2020 election win.
“Was that the liberal left? Or the toothless army who stormed the Capitol on January 6,” said Kimmel.
His remarks saw the chairman of the Federal Communications Commission, Trump backer Brendan Carr, threaten to “take action” against Disney and ABC.
A representative for Kimmel did not immediately respond to a request for comment about the cancellation.
Celebrities who have guested on his show joined Democrats in speaking out. Wanda Sykes accused Mr Trump of seeking to end freedom of speech, while Ben Stiller tweeted: “This isn’t right.”
The latest season of Jimmy Kimmel Live averaged 1.57 million viewers per episode, according to media research firm Nielsen – and the show’s YouTube channel has almost 21 million subscribers.
Kimmel follows in Colbert’s footsteps
The abrupt removal of Jimmy Kimmel Live comes after fellow late night host Stephen Colbert saw his programme cancelled, which fans claimed was a result of his criticism of Mr Trump.
Mr Trump presents himself as a staunch advocate of free speech, but regularly rails against media organisations which criticise him. This week he launched a lawsuit against The New York Times.
CBS announced in July it would end The Late Show when its current series ends next May.
In a statement, the network said the move was “not related in any way to the show’s performance, content or other matters happening at Paramount.”
Mr Trump praised the move, saying “his talent was even worse than his ratings”.
Colbert’s Late Show won an Emmy for outstanding talk series for the first time at the weekend.