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.”
Donald Trump wants to emulate Vladimir Putin and “govern his own country in a similar fashion”, his former national security adviser has said.
Fiona Hill told Sky News’ The World with Yalda Hakim that the US and Russian presidents both share the same view of the world as being “divided up among three major powers; Russia, the US and China, with very clear spheres of influence”.
She said the two leaders “have shockingly similar world views”.
Image: Donald Trump and Vladimir Putin. Pic: Reuters
“This is the first time we’ve had a US president who wants to emulate the Russian leader in some way, who wants to create a hyper-personalised presidency, who wants to basically govern his own country in a very similar fashion, very top down without any checks and balances,” she said.
Ms Hill added Mr Trump wants to “regularise, normalise and reset” the relationship between the US and Russia.
“That’s very clear, it’s been clear since the first presidency of Trump,” she said.
“He’s always wanted to sit down with Vladimir Putin and sort out all of the difficulties in the bilateral relationship, everything from nuclear issues and nuclear arms reduction – there’s all kinds of economic and business deals that Trump himself and his immediate circle are very interested in.
“That was not the direction of travel of other US presidents. So in actual fact there’s probably more chance under Trump of a close relationship between the US and Putin.”
Ms Hill said Mr Trump has an interest in forging a “personal relationship” beyond what he already has with Mr Putin.
“He wants to extricate the United States from its support for Ukraine, he’s said that very clearly,” she said.
“He also wants to pull back from the underpinning of European security and get the Europeans to pick up not just support for Ukraine, but also much more involvement and much more in-depth payment for all of their own security, that’s also very clear.
“So there is a strategic perspective there and I think part of the US strategy and the Trump administration strategy is to push the Europeans to go off essentially on their owns in terms of framing what they want in European security and making it very clear to the Ukrainians that they can’t expect much more future support from the United States.”
Hours after US secretary of state Marco Rubio withdrew from high-level talks in London aimed at ending the conflict, the American president heaped pressure on Volodymyr Zelenskyy to “get it done”.
It’s not that Ukraine’s President Volodymyr Zelenskyy won’t back down, it’s that he can’t.
The US plan to recognise Russia‘s claim to Ukrainian territory it has seized effectively legitimises Moscow’s decision to invade.
To concede that would be a breach of Ukraine’s constitution.
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Ukraine has not hinted at recognising Crimea as Russian ‘for even a day’
The country’s economy minister Yuliia Svyrydenko says they’re “ready to negotiate, not ready to surrender”.
US vice president JD Vance has now stepped into Marco Rubio’s shoes, warning that America will “walk away” if there isn’t a “yes” from both sides.
But President Trump is only talking about one side: Ukraine.
The absence of any reference to Russian President Vladimir Putin in his lengthy post online will not have gone unnoticed.
He claimed no one was asking Zelenskyy to recognise Crimea as Russian, but contradicted that by asking why Ukraine hadn’t fought for Crimea 11 years ago.
President Trump blamed the loss of Crimea on one of his predecessors, his reference to “President Barack Hussein Obama” revealing the depth of his frustration.
He claims he is “very close” to a deal, but the signals from Washington, London, Moscow and Kyiv suggest otherwise.
Right now, it feels like he’s much closer to throwing in the towel and throwing Zelenskyy under the bus. Again.
Global stock markets and the dollar have rallied on hopes of two significant climbdowns by the Trump administration on issues blamed for a slump in values.
Remarks by the US Treasury secretary on punitive tariffs against China lifted the mood on Wall Street initially before the president himself moved to calm market trade war worries and also end speculation he could fire the head of the country’s central bank.
The Dow Jones Industrial Average and tech-focused Nasdaq Composite both ended Tuesday trading 2.7% up, erasing losses of the previous day.
Asian markets later followed that lead, with the Hang Seng in Hong Kong gaining 2.4%.
European indices also saw a strong opening, with the FTSE 100 up by more than 1.2%. It was led higher by Asia-focused banks HSBC and Standard Chartered.
US futures suggested Wall Street would pick up where it left off, with further strong gains expected.
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The US dollar – badly hit by trade war implications in recent weeks – was at least a cent higher than a day earlier against many rival currencies including the pound.
The rally gathered steam on Tuesday evening when US Treasury secretary Scott Bessent told a private JPMorgan event that he expected a “de-escalation” in the spiralling spat with China.
It’s a fight that has seen US tariffs hit 145% and China responding with duties of 125%.
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Trump: Tariffs are making US ‘rich’
According to a transcript obtained by the Associated Press news agency, he told the audience: “Neither side thinks the status quo is sustainable”, but he added that peace talks were yet to start in earnest and could take time to bear fruit.
His boss later struck a similar tone in remarks to reporters when he said the final tariff rate with China would come down “substantially” from the current 145%.
“It won’t be that high, not going to be that high,” Mr Trump said, adding: “We’re doing fine with China… we’re going to live together very happily and ideally work together.”
He gave no hint that he plans to ease wider tariffs on trading partners, including the UK which is currently subject to 25% tariffs on car, steel and aluminium imports and a wider 10% “baseline” tariff.
But the president did row back on an apparent threat, made last week, to sack the chair of the Federal Reserve Jerome Powell in revenge for the US central bank holding off on interest rate cuts that could provide some stimulus to the tariff-hit economy.
Mr Powell has said the Trump administration’s protectionist policies have created uncertainty over growth and the threat of higher inflation.
The president has dismissed those arguments but told reporters: “I have no intention of firing him”.
Image: Federal Reserve chair Jerome Powell was nominated for the role by Donald Trump in 2017. File pic: AP
His comments were widely seen as an attempt to calm financial market concerns that the independence of the country’s central bank was under threat.
Analysts cautioned there was a long way to go to recover values seen before the start of the trade war, with the Nasdaq remaining almost 16% down in the year to date alone.
US government borrowing costs also remain elevated.
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What IMF said about the UK economy
Not helping sentiment were big downgrades to global growth forecasts by the International Monetary Fund on Tuesday.
Michael Brown, senior research strategist at Pepperstone, said of the investor mood: “Participants understandably remain jittery, not only as the haven value of both Treasuries and the USD (US dollar) continue to be called into question, but also as a huge degree of trade uncertainty continues to linger.
“As a reminder, the whole concept of ’90 deals in 90 days’ is currently running at ‘0 deals in 14 days’ which, to be frank, doesn’t quite have the same ring to it.”