The moon exerts a previously unknown tidal force on the “plasma ocean” surrounding Earth’s upper atmosphere, creating fluctuations that are similar to the tides in the oceans, a new study suggests.
In the study, published Jan. 26 in the journal Nature Physics (opens in new tab) , scientists used more than 40 years of data collected by satellites to track the minute changes in the shape of the plasmasphere, the inner region of Earth’s magnetosphere, which shields our planet from solar storms and other types of high-energy particles.
The plasmasphere is a roughly doughnut-shaped blob of cool plasma that sits on top of Earth’s magnetic field lines, just above the ionosphere, the electrically charged part of the upper atmosphere. The plasma, or ionized gas, in the plasmasphere is denser than the plasma in the outer regions of the magnetosphere, which causes it to sink to the bottom of the magnetosphere. The boundary between this dense sunken plasma and the rest of the magnetosphere is known as the plasmapause.
“Given its cold, dense plasma properties, the plasmasphere can be regarded as a ‘plasma ocean,’ and the plasmapause represents the ‘surface’ of this ocean,” the researchers wrote in the paper. The moon’s gravitational pull can distort this “ocean,” causing its surface to rise and fall like the ocean tides.
Related: Colossal asteroid impact forever changed the balance of the moon
The moon is already known to exert tidal forces on Earth’s oceans, crust, near-ground geomagnetic field and the gas within the lower atmosphere. However, until now, nobody had tested to see if there was a tidal effect on the plasmasphere.
To investigate this question, the researchers analyzed data from more than 50,000 crossings of the plasmasphere by satellites belonging to 10 scientific missions, including NASA’s Time History of Events and Macroscale Interactions during Substorms (THEMIS) mission. The satellites’ sensors are capable of detecting minute changes in the concentrations of plasma, which allowed the team to map out the exact boundary of the plasmapause in greater detail than ever before.
The satellite crossings occurred between 1977 and 2015, and during this period, there were four complete solar cycles. This information allowed the team to factor in the role of solar activity on Earth’s magnetosphere. Once the sun’s influence was accounted for, it started to become clear that fluctuations in the shape of the plasmapause followed daily and monthly patterns that were very similar to the ocean’s tides, indicating that the moon was the most likely cause of the plasma tides.
The researchers are unsure exactly how the moon causes the plasma tides, but their current best guess is that the moon’s gravity causes perturbations in Earth’s electromagnetic field. But further research is needed to tell for sure.
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The team thinks this previously unknown interaction between Earth and the moon could help researchers understand other parts of the magnetosphere in greater detail, such as the Van Allen radiation belts, which capture highly energetic particles from solar wind and trap them in the outer magnetosphere.
“We suspect that the observed plasma tide may subtly affect the distribution of energetic radiation belt particles, which are a well-known hazard to space-based infrastructure and human activities in space,” the researchers wrote. Better understanding the tides could therefore help to improve work in these areas, they added.
The researchers also want to see if plasma in the magnetospheres of other planets is influenced by those planets’ moons. “These findings may have implications for tidal interactions in other two-body celestial systems,” they wrote.
Ukrainians say they are in danger of losing the drone arms race with Russia and need more help.
And that is worrying not just for Ukraine, because the drone is becoming the likely weapon of choice in other future conflicts.
Sky News has been given exclusive access to a Ukrainian drone factory to watch its start up ingenuity at work. Ukrainians have turned the drone into their most effective weapon against the invaders.
But they are now, we are told, losing the upper hand in the skies over Ukraine.
General Cherry Drones was started by volunteers at the beginning of the war, making a 100 a month, but is now producing 1,000 times that. The company’s Andriy Lavrenovych said it is never enough.
Image: Andriy Lavrenovych
“The Russians have a lot of troops, a lot of vehicles and our soldiers every day tell us we need more, we need more weapons, we need better, we need faster, we need higher.”
The comments echo the words of Ukraine’s leader, President Volodymyr Zelenskyy, who told reporters this week “the Russians have increased the number of drones, while due to a lack of funding, we have not yet been able to scale up.”
The factory’s location is a closely-guarded secret, moved often. Russia strikes weapons factories when it can.
In a nondescript office building we watched drones being assembled and stacked in their thousands. Put together like toys, they are hand assembled and customised.
The quadcopters vary in size, some carry explosives to attack the enemy. Others fly as high as six kilometres to ambush Russian surveillance drones.
Image: A combat drone is prepared by a Ukrainian soldier in the frontline town of Chasiv Yar. Pic:24th King Danylo Separate Brigade/Reuters
A $1,000 (£743) Ukrainian drone can bring down an enemy aircraft worth 300 times as much.
Downstairs each drone is tested before it’s sent to the front. Nineteen-year-old Dima – not his real name – used to play with drones at home before it was occupied in Kherson Oblast.
Now he works here using his skills to check the drones are fit for battle.
But Russia is catching up. Sinister propaganda released this week filmed at one of its vast new drone factories shows hundreds of Geranium delta wing attack drones lined up ready to be launched at Ukraine.
Russia has refined the technology provided by Iranians to produce faster, more lethal versions of their Shahed drones. They have wreaked havoc and carnage, coming in their hundreds every night and killing scores of civilians. Ukraine expects 1,000 a night in the months ahead.
Russia is using scale and quantity to turn the tables on Ukrainians. And it is mastering drones controlled by fibre optic thread, trailing in their wake, that cannot be jammed.
Image: Oleksandr “Drakar”, head of new product development
Oleksandr “Drakar”, head of new product development, showed us his company’s prototype fibre optic model. It is more effective than the Russians, he told us, but added: “The Russians began using the technology earlier and have scaled up production.
“They’ve had considerable help from the Chinese – entire factories there are under contract to supply fibre exclusively to Russia, producing it in vast quantities.”
Russia’s Chinese allies, who claim to be neutral in this conflict, are also throttling the supply of microchips and other parts vital to drone production. The West is not doing enough, say Ukrainians, to counterbalance the threat.
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16:01
Is NATO ready for drone war?
It is a constant race to beat the other side, innovation met by more innovation. This conflict is revolutionising warfare into a sci-fi battle of machines.
Ukrainians say 80% of battlefield strikes are now carried out by drones.
Whoever has the upper hand with them in this conflict is likely to have the edge in future wars. If the West wants to be on the winning side, it will need to give Zelenskyy and his drone start-up companies more help to maintain their edge.
Nigel Farage has said he would scrap the UK’s human rights law to enable the mass deportation of illegal migrants, as the government reportedly prepares to send more than 100 small boat arrivals back to France.
Writing in The Daily Telegraph ahead of a speech later today, the Reform leader said the Human Rights Act would be ripped up should he become prime minister.
He would also take the country out of the European Convention on Human Rights (ECHR) and other international treaties, describing them as “malign influences” which had been “allowed to frustrate deportations”.
Pulling Britain out of the ECHR would make it one of only three European countries not signed up – the others being Russia and Belarus.
The UK’s Human Rights Act, Reform say, would be replaced by a British Bill of Rights. This would only apply to British citizens and those with a legal right to live in the UK.
Small boat arrivals would have no right to claim asylum. They would be housed at old military bases before being deported to their country of origin, or third countries like Rwanda.
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1:35
Will Starmer’s migration tough talk deliver?
One in, one out
Sir Keir Starmer, meanwhile, is said to be ready to implement one of his major policies to tackle the small boats crisis within weeks.
According to The Times, the one in, one out migrant deal he signed with France’s Emmanuel Macron earlier this summer will soon see more than 100 people sent back.
The newspaper reported there are dozens of migrants currently in detention, including some arrested over the bank holiday weekend, who could be among the first sent back to France.
In exchange, the UK would be expected to take an equal number of asylum seekers in France with ties to Britain.
Protests have taken place outside hotels used to house asylum seekers over the weekend, and the government is braced for more legal challenges from councils over their use.
Labour have taken a battering in the opinion polls throughout 2025, with Reform consistently in the lead.
US rapper Lil Nas X has pleaded not guilty after being charged with assaulting a police officer while walking in downtown Los Angeles in his underwear.
The musician, real name Montero Lamar Hill, was taken to hospital and arrested after police responded to reports of a naked man shortly before 6am on Thursday.
The district attorney’s office said on Monday that Lil Nas X faces three counts of battery with injury on a police officer and one count of resisting an executive officer.
He was being held on a $75,000 (£55,457) bail, conditional on attending drug treatment. It is not immediately clear whether he had posted it and been released yet.
He is set to return to court on 15 September for his next pre-trial hearing.
Image: Pic: AP
During the hearing on Monday, Hill’s lawyer Christy O’Connor told the judge he had led a “remarkable” life, adding: “Assuming the allegations here are true, this is an absolute aberration in this person’s life.
“Nothing like this has ever happened to him.”
A law enforcement source told Sky’s US partner network, NBC News, on Thursday that the Old Town Road and Industry Baby hitmaker punched an officer twice in the face during the encounter.
The source added officers were unsure whether he was on any substances or in mental distress.
NBC News cited TMZ footage where Hill was seen walking down the middle of Ventura Boulevard at 4am on Thursday in a pair of white briefs and cowboy boots.
In the videos, Hill tells a driver to “come to the party” in one clip and in another tells the person: “Didn’t I tell you to put the phone down?”
“Uh oh, someone’s going to have to pay for that,” Hill says as he continues to walk away.
In some clips, Hill struts as if he’s on a catwalk, posing for onlookers, and at one point he places an orange traffic cone on his head.