The Odd Behavior of a Subatomic Particle May Shake up Physics

The Muon g-2 ring sits in its detector hall at US Department of Energy's Fermi National Accelerator Laboratory (Fermilab) in Batavia, Illinois, US, in an undated handout photo. (Fermi National Accelerator Laboratory/Ryan Postel/Handout via Reuters)
The Muon g-2 ring sits in its detector hall at US Department of Energy's Fermi National Accelerator Laboratory (Fermilab) in Batavia, Illinois, US, in an undated handout photo. (Fermi National Accelerator Laboratory/Ryan Postel/Handout via Reuters)
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The Odd Behavior of a Subatomic Particle May Shake up Physics

The Muon g-2 ring sits in its detector hall at US Department of Energy's Fermi National Accelerator Laboratory (Fermilab) in Batavia, Illinois, US, in an undated handout photo. (Fermi National Accelerator Laboratory/Ryan Postel/Handout via Reuters)
The Muon g-2 ring sits in its detector hall at US Department of Energy's Fermi National Accelerator Laboratory (Fermilab) in Batavia, Illinois, US, in an undated handout photo. (Fermi National Accelerator Laboratory/Ryan Postel/Handout via Reuters)

The peculiar wobble of a subatomic particle called a muon in a US laboratory experiment is making scientists increasingly suspect they are missing something in their understanding of physics - perhaps some unknown particle or force.

Researchers on Thursday announced new findings about the muon (pronounced MEW-on), a magnetic and negatively charged particle similar to its cousin the electron but 200 times more massive, in their experiment at the US Energy Department's Fermi National Accelerator Laboratory in Batavia, Illinois.

The experiment studied the wobble of muons as they traveled through a magnetic field. The muon, like the electron, has a tiny internal magnet that causes it to wobble - or, technically speaking, "precess" - like the axis of a spinning top while in a magnetic field.

But the wobble's speed, as measured in the experiment, varied considerably from what was predicted based on the Standard Model of particle physics, the theory that explains how the basic building blocks of matter interact, governed by four fundamental forces in the universe.

The new findings, building on data released in 2021, continue to hint at some mysterious factor at play as the researchers try to sort out the discrepancy between the theoretical prediction and the actual experimental results.

"We are looking for an indication that the muon is interacting with something that we do not know about. It could be anything: new particles, new forces, new dimensions, new features of space-time, anything," said Brendan Casey, a senior scientist at Fermilab and one of the authors of a research paper on the findings published in the journal Physical Review Letters.

"I like crazy so I would love this to be something like Lorentz violation or some other new property of space-time itself. That would be insane and revolutionary," Casey added.

Casey was alluding to a principle called Lorentz invariance that holds that the laws of physics are the same everywhere.

"Yes, it is fair to say that it could be pointing to unknown particles or forces," University College London physicist and study co-author Rebecca Chislett said. "Currently due to new results in the theory community, it is difficult to say exactly what the discrepancy between the two (predicted muon behavior and observed behavior) is, but theorists are working hard to resolve this."

The experiment was conducted at minus-450 degrees Fahrenheit (minus-268 degrees Celsius). The researchers shot beams of muons into a donut-shaped superconducting magnetic storage ring measuring 50 feet (15 meters) in diameter. As the muons zipped around the ring traveling nearly the speed of light, they interacted with other subatomic particles that, like tiny dance partners, altered their wobble.

The 2021 results similarly showed an anomalous wobble. The new results were based on quadruple the amount of data, bolstering confidence in the findings.

"With all this new knowledge, the result still agrees with the previous results and this is hugely exciting," Chislett said.

The researchers hope to announce their final findings using all of their collected data in about two years.

"The experiment measures how fast muons spin in a magnetic field. The concept is simple. But to get to the required precision takes years of building the experiment and taking data. We took data from 2018 to 2023. The new result is based on our 2019 and 2020 data," Casey said.

"We have to be patient because we need the Standard Model prediction to catch up to us for us to make the strongest use of our data," Casey added. "We are also very baffled because there are different ways to predict what our experiment should see and they don't agree well. So there is something very fundamental here we must be missing, which is very intriguing."



Saturn's Moon Titan May Not Have a Buried Ocean as Long Suspected, New Study Suggests

This image made by the Cassini spacecraft and provided by NASA on March 12, 2006, shows two of Saturn's moons, the small Epimetheus and smog-enshrouded Titan, with Saturn's A and F rings stretching across the frame. (NASA via AP)
This image made by the Cassini spacecraft and provided by NASA on March 12, 2006, shows two of Saturn's moons, the small Epimetheus and smog-enshrouded Titan, with Saturn's A and F rings stretching across the frame. (NASA via AP)
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Saturn's Moon Titan May Not Have a Buried Ocean as Long Suspected, New Study Suggests

This image made by the Cassini spacecraft and provided by NASA on March 12, 2006, shows two of Saturn's moons, the small Epimetheus and smog-enshrouded Titan, with Saturn's A and F rings stretching across the frame. (NASA via AP)
This image made by the Cassini spacecraft and provided by NASA on March 12, 2006, shows two of Saturn's moons, the small Epimetheus and smog-enshrouded Titan, with Saturn's A and F rings stretching across the frame. (NASA via AP)

Saturn's giant moon Titan may not have a vast underground ocean after all.

Titan instead may hold deep layers of ice and slush more akin to Earth’s polar seas, with pockets of melted water where life could possibly survive and even thrive, scientists reported Wednesday.

The team led by researchers at NASA's Jet Propulsion Laboratory challenged the decade-long assumption of a buried global ocean at Titan after taking a fresh look at observations made years ago by NASA’s Cassini spacecraft around Saturn.

They stress that no one has found any signs of life at Titan, the solar system’s second largest moon spanning 3,200 miles (5,150 kilometers) and brimming with lakes of liquid methane on its frosty surface, The AP news reported.

But with the latest findings suggesting a slushy, near-melting environment, “there is strong justification for continued optimism regarding the potential for extraterrestrial life,” said the University of Washington’s Baptiste Journaux, who took part in the study published in the journal Nature.

As to what form of life that might be, possibly strictly microscopic, “nature has repeatedly demonstrated far greater creativity than the most imaginative scientists," he said in an email.

JPL’s Flavio Petricca, the lead author, said Titan’s ocean may have frozen in the past and is currently melting, or its hydrosphere might be evolving toward complete freezing.

Computer models suggest these layers of ice, slush and water extend to a depth of more than 340 miles (550 kilometers). The outer ice shell is thought to be about 100 miles (170 kilometers) deep, covering layers of slush and pools of water that could go down another 250 miles (400 kilometers). This water could be as warm as 68 degrees Fahrenheit (20 degrees Celsius).

Because Titan is tidally locked, the same side of the moon faces Saturn all the time, just like our own moon and Earth. Saturn’s gravitational pull is so intense that it deforms the moon’s surface, creating bulges as high as 30 feet (10 meters) when the two bodies are closest.

Through improved data processing, Petricca and his team managed to measure the timing between the peak gravitational tug and the rising of Titan’s surface. If the moon held a wet ocean, the effect would be immediate, Petricca said, but a 15-hour gap was detected, indicating an interior of slushy ice with pockets of liquid water. Computer modeling of Titan’s orientation in space supported their theory.

Sapienza University of Rome’s Luciano Iess, whose previous studies using Cassini data indicated a hidden ocean at Titan, is not convinced by the latest findings.

While “certainly intriguing and will stimulate renewed discussion ... at present, the available evidence looks certainly not sufficient to exclude Titan from the family of ocean worlds," Iess said in an email.

NASA’s planned Dragonfly mission — featuring a helicopter-type craft due to launch to Titan later this decade — is expected to provide more clarity on the moon’s innards. Journaux is part of that team.

Saturn leads the solar system’s moon inventory with 274. Jupiter’s moon Ganymede is just a little larger than Titan, with a possible underground ocean. Other suspected water worlds include Saturn’s Enceladus and Jupiter’s Europa, both of which are believed to have geysers of water erupting from their frozen crusts.

Launched in 1997, Cassini reached Saturn in 2004, orbiting the ringed planet and flying past its moons until deliberately plunging through Saturn’s atmosphere in 2017.


Catch the Ursid Meteor Shower as it Peaks just before Christmas

People look up to the sky from an observatory near the village of Avren, Bulgaria, Aug. 12, 2009. (AP Photo/Petar Petrov, File)
People look up to the sky from an observatory near the village of Avren, Bulgaria, Aug. 12, 2009. (AP Photo/Petar Petrov, File)
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Catch the Ursid Meteor Shower as it Peaks just before Christmas

People look up to the sky from an observatory near the village of Avren, Bulgaria, Aug. 12, 2009. (AP Photo/Petar Petrov, File)
People look up to the sky from an observatory near the village of Avren, Bulgaria, Aug. 12, 2009. (AP Photo/Petar Petrov, File)

The last major meteor shower of the year, known as the Ursids, peaks soon, bringing glowing streaks to nighttime and early morning skies. Compared to other meteor showers, it's more subdued, but experts say it's still worth a glimpse.

Meteor showers happen when space rocks hit Earth's atmosphere at extremely high speeds and burn up, gaining fiery tails — the end of a “shooting star.” Random meteors are visible from Earth on any given clear night, but more predictable meteor showers happen yearly when Earth passes through streams of cosmic leftovers from comets or asteroids, Reuters reported.

The Ursids peak Sunday night into Monday morning and will be visible until Dec. 26 from the Northern Hemisphere. Skygazers usually see five to 10 meteors per hour during the height and there's a possibility for outbursts of up to 25 meteors per hour, according to the American Meteor Society.

How active a shower will appear from Earth depends on the amount of debris and the moon's brightness, which can blot out glowing meteors. The Ursids feature less space debris than other showers like the Geminids, but the narrow crescent moon won't be much of an obstacle when they peak.

No special equipment is needed to view a meteor shower. To see the Ursids, which hail from a comet called 8P/Tuttle, bundle up and get away from city lights.

“The darker your sky, the better the shower is going to be,” said astronomer Peter Brown with Western University in Canada.

The meteors can be seen over the whole sky, but all the streaks will seem to come from a central point near a constellation for which the shower is named. In this case, that's the constellation Ursa Minor, also known as the Little Dipper.

Once it gets dark, avoid bright lights from cellphones, which will make it harder for your eyes to adjust.


Private Astronaut Jared Isaacman Becomes NASA Chief

NASA's next-generation moon rocket, the Space Launch System (SLS) rocket with its Orion crew capsule perched on top, is seen in the Vehicle Assembly Building (VAB) before it is scheduled to make a slow-motion journey to its launch pad at Cape Canaveral, Florida, US March 16, 2022. REUTERS/Thom Baur
NASA's next-generation moon rocket, the Space Launch System (SLS) rocket with its Orion crew capsule perched on top, is seen in the Vehicle Assembly Building (VAB) before it is scheduled to make a slow-motion journey to its launch pad at Cape Canaveral, Florida, US March 16, 2022. REUTERS/Thom Baur
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Private Astronaut Jared Isaacman Becomes NASA Chief

NASA's next-generation moon rocket, the Space Launch System (SLS) rocket with its Orion crew capsule perched on top, is seen in the Vehicle Assembly Building (VAB) before it is scheduled to make a slow-motion journey to its launch pad at Cape Canaveral, Florida, US March 16, 2022. REUTERS/Thom Baur
NASA's next-generation moon rocket, the Space Launch System (SLS) rocket with its Orion crew capsule perched on top, is seen in the Vehicle Assembly Building (VAB) before it is scheduled to make a slow-motion journey to its launch pad at Cape Canaveral, Florida, US March 16, 2022. REUTERS/Thom Baur

The US Senate confirmed billionaire private astronaut Jared Isaacman to become President Donald Trump's NASA administrator, making an advocate of Mars missions and a former associate of SpaceX CEO Elon Musk the space agency's 15th leader. The vote on Isaacman, who Trump removed and then renamed as NASA administrator nominee this year, passed 67-30, two weeks after he told senators in his second hearing that NASA must pick up the pace in beating China back to the moon this decade, Reuters reported.

Isaacman will lead an agency of 14,000 employees as it invests billions of dollars into its most ambitious space exploration endeavor yet: returning humans to the moon to seed a long-term presence on the surface before eventually sending astronauts to Mars.

NASA WORKFORCE CUT IN EFFICIENCY PUSH

The White House, in its government efficiency push led by Musk, slashed NASA's workforce by 20% and has sought to cut the agency's 2026 budget by roughly 25% from its usual $25 billion, imperiling dozens of space-science programs that scientists and some officials regard as priorities.

Isaacman envisions a revamped focus on sending missions to Mars on top of the Artemis moon effort, as well as a greater dependence on private companies such as SpaceX to save taxpayer money and stimulate private-sector competition.

Of the 67 votes in Isaacman's favor, 16 were from Democrats, joining 51 from Republicans. All 30 votes against his confirmation were from Democrats.

Maria Cantwell, the ranking member of the Senate Commerce Committee that oversees NASA, has criticized the Trump administration's efforts to cut NASA's science unit. She supported Isaacman's confirmation on Wednesday.

"During his nomination process, Mr. Isaacman emphasized the importance of developing a pipeline of future scientists, engineers, researchers, (and) astronauts to support the science and technology development and align with NASA's objectives. I strongly agree," Cantwell said.

Some Democratic senators said during Isaacman's hearing on December 3 they are concerned about Isaacman's closeness to Musk, whose company holds about $15 billion in NASA contracts and could benefit from certain policies Isaacman has advocated.

Musk advocated for Isaacman's nomination when Trump was elected in 2024. Musk had sought to realign the US space program with a greater focus on Mars during his stint as a close adviser to Trump.

Senate Republicans and some Democrats, including Cantwell, have also stressed urgency in NASA's moon race with China, which is aiming to send its astronauts to the lunar surface by 2030. NASA faces a shaky target of 2028 using its Space Launch System rocket and SpaceX's giant Starship rocket, under development, as the lander.

Acting NASA chief Sean Duffy, who also leads the US Transportation Department, congratulated Isaacman on X, wishing Isaacman "success as he begins his tenure and leads NASA as we go back to the Moon in 2028 and beat China."