North Korea set off an earthshaking explosion -- and claimed it was nuclear. Was it? For scientists, that was not a quick and easy question to answer.
Like earthquakes, large explosions send out shockwaves that can be detected with seismographs. Big nuclear bombs make big waves, with clear signatures that make them fairly easy to detect, analyze and confirm that they were caused by splitting atoms.
But smaller blasts -- as North Korea's appears to have been -- are trickier to break down.
The natural sound of the Earth, caused by tectonic plates grinding together, complicates the task of trying to determine if a blast was caused by conventional explosives or a nuclear bomb, said Xavier Clement of France's Atomic Energy Commission.
He likened the problem to trying to "detect the violins or a flute in a symphony orchestra when you are playing the cymbals."
His agency estimated the North Korean blast at around one kilotonne or less -- equivalent to the explosive force of 1,000 tonnes of TNT. For a nuclear device, that would be so weak that the French defense minister suggested that "there could have been a failure" with North Korea's reported test.
Clement said it could take days before scientists can declare with certainty whether the explosion was nuclear or not.
When blasts are very weak, "we could be in a situation where we cannot tell the difference," he said.
The US, Russia, China, Japan and South Korea are among the countries with equipment strong enough and close enough to monitor a North Korean test, according to Russian nuclear physicist Vladimir Orlov of the PIR Center, a nonproliferation think tank.
"It takes days, dozens of lab hours, to evaluate. Now we have only a rough estimate," he said.
The Comprehensive Nuclear Test Ban Treaty Organization (CTBTO), has about 200 stations worldwide to monitor nuclear tests as part of what it hopes will become the world's most reliable source of data for such tests. But until the treaty comes into force, the data is not made public, only released to governments and vetted partners.
Seismic data comes in almost immediately, and is usually passed to governments within an hour or so. Their scientists must decide what the numbers mean.
With the North Korean blast, there were wide variations. While the French atomic agency estimated around one kilotonne and South Korea's geological institute 0.5 kilotonnes, Russia's defense minister said there was "no doubt" that North Korea detonated a nuclear test and said the force of the underground blast was equivalent to 5,000 to 15,000 tonnes of TNT.
"People have different ways of cross-cutting the data and interpreting it," said Lassina Zerbo, director of the International Data Center at the CTBTO, which is based in Vienna, Austria.
The test ban treaty, which bans all types of nuclear explosions, whether tests or otherwise, will not enter into force until it has been ratified by 44 states that currently possess either nuclear weapons capability or nuclear research reactors.
So far 34 have ratified it. Nations that have not signed include the US, China, India, Pakistan, Israel and North Korea.
Indonesia yesterday began enforcing its newly ratified penal code, replacing a Dutch-era criminal law that had governed the country for more than 80 years and marking a major shift in its legal landscape. Since proclaiming independence in 1945, the Southeast Asian country had continued to operate under a colonial framework widely criticized as outdated and misaligned with Indonesia’s social values. Efforts to revise the code stalled for decades as lawmakers debated how to balance human rights, religious norms and local traditions in the world’s most populous Muslim-majority nation. The 345-page Indonesian Penal Code, known as the KUHP, was passed in 2022. It
‘DISRESPECTFUL’: Katie Miller, the wife of Trump’s most influential adviser, drew ire by posting an image of Greenland in the colors of the US flag, captioning it ‘SOON’ US President Donald Trump on Sunday doubled down on his claim that Greenland should become part of the US, despite calls by the Danish prime minister to stop “threatening” the territory. Washington’s military intervention in Venezuela has reignited fears for Greenland, which Trump has repeatedly said he wants to annex, given its strategic location in the arctic. While aboard Air Force One en route to Washington, Trump reiterated the goal. “We need Greenland from the standpoint of national security, and Denmark is not going to be able to do it,” he said in response to a reporter’s question. “We’ll worry about Greenland in
PERILOUS JOURNEY: Over just a matter of days last month, about 1,600 Afghans who were at risk of perishing due to the cold weather were rescued in the mountains Habibullah set off from his home in western Afghanistan determined to find work in Iran, only for the 15-year-old to freeze to death while walking across the mountainous frontier. “He was forced to go, to bring food for the family,” his mother, Mah Jan, said at her mud home in Ghunjan village. “We have no food to eat, we have no clothes to wear. The house in which I live has no electricity, no water. I have no proper window, nothing to burn for heating,” she added, clutching a photograph of her son. Habibullah was one of at least 18 migrants who died
Russia early yesterday bombarded Ukraine, killing two people in the Kyiv region, authorities said on the eve of a diplomatic summit in France. A nationwide siren was issued just after midnight, while Ukraine’s military said air defenses were operating in several places. In the capital, a private medical facility caught fire as a result of the Russian strikes, killing one person and wounding three others, the State Emergency Service of Kyiv said. It released images of rescuers removing people on stretchers from a gutted building. Another pre-dawn attack on the neighboring city of Fastiv killed one man in his 70s, Kyiv Governor Mykola