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Sunday, February 27, 2022

Supreme Court Will Hear Biggest Climate Change Case in a Decade

The court could handcuff President Biden’s climate change agenda — and restrict federal agencies from enacting new regulations governing health, workplace safety and more.

WASHINGTON — In the most important environmental case in more than a decade, the Supreme Court on Monday will hear arguments in a dispute that could restrict or even eliminate the Environmental Protection Agency’s authority to control the pollution that is heating the planet.

A decision by the high court, with its conservative supermajority, could shred President Biden’s plans to halve the nation’s greenhouse emissions by the end of the decade, which scientists said is necessary to avert the most catastrophic impacts of climate change.

“They could handcuff the federal government’s ability to affordably reduce greenhouse gases from power plants,” said Michael Oppenheimer, a professor of geosciences and international affairs at Princeton University.

But the outcome could also have repercussions that stretch well beyond air pollution, restricting the ability of federal agencies to regulate health care, workplace safety, telecommunications, the financial sector and more.

“If the court were to require the E.P.A. to have very specific, narrow direction to address greenhouse gases, as a practical matter it could be devastating for other agencies’ abilities to enact rules that safeguard the public health and welfare of the nation,” said Richard Lazarus, a professor of environmental law at Harvard. “It would restrict the enactment of regulations under any host of federal statutes — OSHA, the Clean Water Act, hazardous waste regulation. In theory it even could limit the Fed’s authority to set interest rates.”

At issue is a federal regulation that broadly governs emissions from power plants. But in a curious twist, the regulation actually never took effect and does not currently exist.

The legal wrangling began in 2015 when President Barack Obama announced the Clean Power Plan, his chief strategy to fight climate change. Citing its authority under the Clean Air Act, the Obama administration planned to require each state to lower carbon dioxide emissions from the electricity sector — primarily by replacing coal-fired power plants with wind, solar and other clean sources. Electricity generation is the second largest source of greenhouse gas emissions in the United States, behind transportation.

But the Clean Power Plan was never implemented. After a barrage of lawsuits from Republican states and the coal industry, the Supreme Court put the program on hold. Once President Donald J. Trump took office, he instituted a new plan that was effectively the same as no regulation. But on the last full day of Mr. Trump’s presidency, a federal appeals court found that the Trump administration had “misconceived the law” and vacated the Trump plan. That cleared the way for the Biden administration to issue its own regulation, which it has yet to do.

It is highly unusual for the Supreme Court to take up a case that revolves around a hypothetical future regulation, legal experts said.

“Trying to figure out the contours of E.P.A.’s authority to regulate greenhouse gases when there’s no regulation being defended is just kind of a weird thing for the court to consider,” said Jonathan Adler, a law professor at Case Western Reserve University. “I was surprised when they took the case.”

Evan Vucci/Associated Press

The plaintiffs in the case, West Virginia v. Environmental Protection Agency, want the high court to block the kind of sweeping changes to the electricity sector that defined the Obama Clean Power Plan.

Instead, Republican attorneys general in 18 states and some of the nation’s largest coal companies will argue that the 1970 Clean Air Act limits the E.P.A. to dictate changes only at individual power plants, not across the entire power sector.

Conservatives have long argued that the executive branch routinely oversteps the authority granted by the Constitution in regulating all kinds of economic activity.

“This is really about a fundamental question of who decides the major issues of the day,” said Patrick Morrisey, the attorney general of West Virginia, speaking at an event in Washington earlier this month, ahead of his appearance before the Supreme Court on Monday. “Should it be unelected bureaucrats, or should it be the people’s representatives in Congress? That’s what this case is all about. It’s very straightforward.”

Others maintain that Congress delegated authority to the executive branch to broadly regulate air pollution under the Clean Air Act. The legislature makes the law; the executive implements it through regulation, they say.

“Just because the opponents are particularly shrill in their objection doesn’t change the fact that this regulation is no different than hundreds of regulation that the agencies have produced since the New Deal — just as Congress intended them to do,” said Richard Revesz, who teaches environmental law at New York University and filed a brief in support of the administration.

With the stakes high, each side has drawn legal backing from an array of supporters. Significantly, many of the nation’s largest electric utilities — the companies that would be subject to environmental regulation — have filed legal briefs in support of the government. They are joined by 192 members of Congress, the U.S. Conference of Mayors, climate and public health advocates and tech giants like Apple, Google and Netflix.

Lining up behind the plaintiffs are 91 members of Congress and some of the nation’s most powerful conservative groups, including Americans for Prosperity Foundation, a group affiliated with the libertarian Koch family and their billions.

Mr. Morrissey suggested that he was encouraged by the 6-3 split on the court between conservatives and liberals, including a trio of Trump appointees. “We have optimism about the result we’re going to get,” he said.

Biden administration officials and environmentalists concede that given both the composition of the court and its recent decisions against federal rules, such as blocking a federal vaccine mandate and ending Mr. Biden’s eviction moratorium, Mr. Morrissey’s optimism is probably well-founded.

“This is certainly a court that is not friendly to government action,” said David Doniger, a lawyer for the Natural Resources Defense Council. “But there are some reasons why we have a fighting chance.”

A spokesman for the Justice Department declined to discuss the case ahead of the oral arguments. But in its brief to the court, the Biden administration urged the court to dismiss the case, noting of the plaintiffs that “the current absence of any federal greenhouse gas regulation causes them no tangible harm.”

That argument may resonate with Justice Brett Kavanaugh, one of the conservatives on the court, who first heard the West Virginia case against the Obama power plant regulation when he was a federal appeals judge in 2015.

Everything you wanted to know about the giant squid











As they live in the deep sea, giant squid are really hard to study. Much of our information has been pieced together from animals that have washed up on beaches or have been captured in fishing nets. Modern techniques using deep-sea cameras have allowed us to capture them on film a handful of times, but there is still much we don’t fully understand about their lifestyle and behaviour.



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How big is a giant squid?


The giant squid is the longest cephalopod out there. That’s the class of molluscs that includes squid, cuttlefish and octopuses. While there have been claims of these ocean giants achieving lengths of 15 or 20 metres, in reality they reach a far more modest 12 to 13 metres. At least, that’s the size of the largest well-preserved individual that has been scientifically recorded. Who knows if there could be a bigger one out there?


The massive molluscs usually weigh around 200-280kg, according to scientific records, but there is one chonky individual that tipped the scales at 317.62kg.



Dead giant squid
Dead giant squid specimen, minus its two feeding tentacles © Wikimedia Commons

What do giant squid look like?


Much like other squid species, the giant squid is characterised by a squishy elongated body, huge eyes, a beak, eight arms and two tentacles. Whereas most squid are pretty small, the giant squid is the supersized version.


When you look at a squid, it has a mantle, which is the ‘body’ of the squid where all the internal organs are located. The mantle has small fins at the end, used for moving around. Then there is the head, and finally the arms and tentacles. When scientists are establishing the size of a squid, they will take measurements of the mantle length as well as the total length. Mantle length can be considered a more reliable measurement, as the arms and tentacles can be stretched out like elastic, making the animal seem far longer than it really is.


How many tentacles does a giant squid have?


Cephalopod limbs seem to get the best of us in a tangle. Do they have arms, legs or tentacles? For a start, all cephalopods have appendages that extend from their head and encircle their beaks. Generally, arms have suckers along most of their length, while tentacles only have suckers at the end.


Octopuses have eight arms and no tentacles, whereas squid and cuttlefish have eight arms and two tentacles. Most male cephalopods will have a specialised arm to deliver sperm to the female. Giant squid are no different to their smaller relatives. They have eight arms and two longer tentacles.


But that’s not all. The suckers on the giant squid’s tentacles and arms measure between two and five centimetres in diameter. These suckers are lined with a sharp, serrated ring of chitin; this tough substance is also found in cephalopod beaks, as well the exoskeletons of insects. When the squid grabs its prey, the suckers’ jagged teeth, combined with suction, allow the squid to hang on tight so the animal cannot escape. It is not unusual to find circular scars around the head and mouth of sperm whales that have snacked on giant squid, and then had to deal with a many-armed meal that fights back.



Giant squid suckers
Giant squid suckers have jagged structures to help them hang onto their prey © Alamy

When were giant squid discovered?


Aristotle talked about a large squid in Historia Animalium, while Pliny the Elder also described a huge squid with arms measuring more than nine metres in length. Tales of gargantuan sea monsters have been common for centuries, and then there is the Norse legend of the ferocious kraken.


It wasn’t until 1857 that the Danish zoologist Japetus Steenstrup compiled stories, reports of washed-up animals, and one very large squid beak to confirm that an enormous squid indeed lurked in the ocean. He named it Architeuthis dux.


Over the years, the number of species of giant squid has been debated. Then in 2004, one nearly complete specimen was accidentally caught by a fishing trawler off the Falkland Islands. The body was immediately frozen and transferred to the Natural History Museum, London, for study and preservation. DNA samples obtained from this specimen, named Archie, helped scientists confirm that there is only one species of giant squid, Architeuthis dux.



What do giant squid eat?


By analysing the stomach contents of dead giant squid, scientists can establish what their recent meals were. It appears that they like to eat deep-sea fish and other squid species. As for cannibalism? We aren’t sure.


They grab the prey with their two feeding tentacles, and draw it towards their sharp, powerful beak, before shredding the unfortunate animal with their radula. The radula is tongue-like organ covered in tiny, toothed structures and is found in many mollusc species, including the humble garden snail. It is used to scrape or rasp at food, whether that’s algae, leaves or flesh.


What eats giant squid?


One perk of being a giant, intelligent animal is that not many animals can eat you. You’re big enough and smart enough to overpower or outwit anything that fancies having a go. Nonetheless, Mr Squiddy isn’t completely undefeatable. Sperm whales and sleeper sharks are known to feed on adult giant squid, while juveniles are a little more vulnerable and may be attacked by smaller whales and sharks, as well as other squid.


Where do giant squid live?


Their inaccessible habitat has made them hard to study, but data gained from sperm whale diving behaviour and trawled specimens suggests they live at depths of 300 to 1,000 metres – yet it is completely possible that they could live even deeper. They are widespread around the world’s oceans, but tend to avoid tropical and polar regions.


Read more about squid:


How long do giant squid live?


Giant squid, like other cephalopods, have an organ called a statocyst, which helps them with orientation and motion. Within the statocyst is a mineralised structure called a statolith. Scientists can use these statoliths to determine the age of cephalopods by counting the statolith’s growth rings – similarly to how you would calculate the age of a tree. Researchers have established that giant squid can live to about five to six years old.


“Most squid live shorter lives, some as short as six months, most about a year,” says squid biologist Dr Sarah McAnulty.  “The longest lived cephalopod I can think of is Graneledone, a deep-sea octopus, and we’re not even totally sure how long they live. It’s just a guess that they live quite a while based on how long they brood their eggs – 4.5 years!


“Some deep-sea animals live an obscenely long time, like the Greenland shark. Five to six years is pretty old for a cephalopod. While it’s not as old as that Greenland shark, it’s still in line with deep animals living longer than shallow animals.”



Old illustration of a giant squid
For decades, scientists had to rely on washed-up specimens of giant squid to study them © Getty Images

How smart is a giant squid?


Cephalopods can problem-solve and are capable of opening containers to extract food, while captive octopuses will need enrichment in their tanks to keep them occupied. Scientists are therefore incredibly interested in studying the ‘intelligence’ of these animals.


We do know that giant squid have a large brain and a complex nervous system, just like other cephalopods. While we haven’t managed to keep any giant squid specimens alive in captivity in order to study them, research conducted in 2020 looked at the giant squid genome and found that it contains around 135 protocadherin genes.


In vertebrates, it is thought that these genes play an important role in wiring up the brain, but they are typically not found large numbers in invertebrates. This research suggests that they could play a similar developmental role in the giant squid, hinting at a complex and highly evolved brain.


Read more about the deep sea:


How big is a giant squid’s eye?


A giant squid has an eye measuring up to 27cm, making it the largest peeper of any animal (although colossal squid eyes may be bigger). To put it into context, that’s about the size of a dinner plate. According to Te Papa museum in Wellington, the giant squid’s eyes are placed on the side of its head, allowing it to see forwards and behind. The colossal squid’s eyes face forwards, giving it binocular vision, which allows it to judge distances.


While large eyes will allow the squid to make the most of any meagre light that reaches the ocean depths, there is another theory as to why they have evolved such massive eyes. A paper published in 2012 in the journal Current Biology suggested that the huge eyes allow the giant squid to detect sperm whales – their main predator – at depth. As the whales move through the water, they disturb plankton and other smaller organisms, causing flashes of bioluminescence. If the giant squid can detect these flashes of light in enough time, they can make a rapid escape.




Giant squid
Giant squid pulled up by zoologist Dr Tsunemi Kubodera in 2006 © Tsunemi Kubodera of the National Science Museum of Japan/AP

What are colossal squid?


Giant squid, colossal squid… nope, scientists aren’t just getting creative with their adjectives, there really is a different species of squid called the colossal squid. While the colossal squid is a bit shorter than the giant squid, measuring up at about 10m, it’s far heavier, reaching a weight of 495kg.


Researchers at Te Papa museum have measured the beak of a colossal squid that they have on display at 42.5mm. Colossal squid beaks found in the stomachs of sperm whales have been measured at 49mm, so the scientists think that bigger colossal squid must be lurking in the ocean’s depth.


When was the first living giant squid photographed?


It wasn’t until 2004 that the first giant squid was photographed while still alive. Zoologist Dr Tsunemi Kubodera and whale watcher Kyoichi Mori went to a known sperm whale hunting ground off the Ogasawara Islands, south of Japan. They dropped a baited line and a camera to a depth of 900m and managed to successfully photograph the squid.


The animal became caught on the line, and when it broke free, it left a tentacle behind. Genetic analysis confirmed the tentacle was from a giant squid, and the researchers say that once the tentacle was back on the boat, “It was still functioning, with the large suckers of the tentacle club repeatedly gripping the boat deck and any offered fingers.”


A few years later, in 2012, scientists hit the jackpot. Kubodera once again travelled to the Ogasawara Islands with deep-sea explorer Edith Widder, who had developed a special camera called Medusa, which uses a low-light system to avoid scaring the squid away. They dropped Medusa to 700 metres and captured a giant squid on film for the first time.



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Later expeditions using Medusa filmed a squid off the coast of the US, as seen in this video.





About our expert 


Dr Sarah McAnulty (@SarahMackAttack) is a squid biologist and science communicator.


Read more about cephalopods:




































#Nature | https://sciencespies.com/nature/everything-you-wanted-to-know-about-the-giant-squid/

Chernobyl Plant Is Unharmed Despite Russian Invasion of Ukraine, Scientists Say

The nation’s 15 operating reactors have also been assessed as safe — at least for the moment.

The failed Chernobyl nuclear power plant in northern Ukraine as well as the nation’s 15 operating reactors are safe and secure amid Russia’s invasion, according to nuclear experts and the International Atomic Energy Agency, an arm of the United Nations that sets safety standards for the world’s nuclear reactors and inspects them for compliance.

“The only real issue is if a nearby target got hit and caused some collateral damage,” said Edwin Lyman, a reactor expert at the Union of Concerned Scientists, a private group in Cambridge, Mass. “I don’t see this as an imminent radiological threat. I don’t think Russia would deliberately target a plant.”

In 1986, the Chernobyl nuclear power plant suffered a meltdown that sent radioactive clouds over parts of Europe and locally left a wasteland of contaminated soil. All four Chernobyl reactors are still shut down, and the plant’s work force closely monitors the safety of Chernobyl’s Unit 4 reactor, which in 1986 exploded and caught fire. An exclusion zone for hundreds of square miles surrounds the abandoned plant to limit public access and inhabitation.

The sprawling plant — some 10 miles from Belarus, a Russian ally — is on one of Russia’s main invasion routes. Western experts said it was in Moscow’s interest to keep Ukraine’s reactors and electrical system running smoothly if its aim was regime change rather than national ruin.

“There’s some risk of a direct hit,” said R. Scott Kemp, a professor of nuclear science at the Massachusetts Institute of Technology. “But I imagine they’ll do everything possible to avoid that because they don’t want to deal with the fallout.”

The bigger threat, Dr. Kemp said, is the degradation of Ukraine’s power grid, which could throw nuclear power plants offline and result in cascading blackouts.

The Ukrainian government said on Thursday on its official website that the Russian invasion and its military takeover of Chernobyl “may cause another ecological disaster.” If the war continues, the government added, a disaster like Chernobyl “can happen again in 2022.”

But nuclear experts rang no strident alarms. Rafael Mariano Grossi, director general of the International Atomic Energy Agency, based in Vienna, said in a statement on Thursday that its Ukrainian counterpart reported that the nation’s 15 nuclear power plants were operating safely. As for the Chernobyl site, he added, the Ukrainian body reported “no casualties nor destruction.”

On Friday, the agency noted reports of “higher radiation measurements at the Chernobyl site” and quoted Ukraine’s nuclear body as saying that the readings may have resulted from heavy military vehicles stirring up soil that the 1986 accident had poisoned.

The stated readings, the agency added, “are low and remain within the operational range measured in the Exclusion Zone since it was established, and therefore do not pose any danger to the public.”

According to the international atomic agency, Ukraine receives a bit more than half of its electricity from its reactors — an unusually high fraction.

Two of Ukraine’s four operational nuclear sites are in its western region — far from Russia’s main invasion routes and presumably out of harm’s way. The other two are in the southern region, much closer to the ongoing military strikes.

The Zaporizhzhia Nuclear Power Plant — the largest of Ukraine’s atomic plants — houses six separate reactors. It sits on the Dnieper River roughly 100 miles north of Crimea. Russia annexed the peninsular part of southern Ukraine in 2014, and the breakaway region serves as a staging area for Russian troops as well as a main invasion route.

US Oil Industry Uses Ukraine Invasion to Push for More Drilling at Home

The goal is “energy security,” lobbyists said, although clean-energy advocates counter that wind and solar provide more protection from boom-and-bust oil markets.

Russian troops hadn’t yet begun their full-on assault on Ukraine late Wednesday when the rallying cry came from the American oil and gas industry.

“As crisis looms in Ukraine, U.S. energy leadership is more important than ever,” the American Petroleum Institute, the powerful industry lobby group, wrote on Twitter with a photo that read: “Let’s unleash American energy. Protect our energy security.”

The crux of the industry’s argument is that any effort to restrain drilling in America makes a world already reeling from high oil prices more dependent on oil and gas from Russia, a rival and belligerent fossil fuel superpower.

The industry’s demands have focused on reversing steps the Biden administration has taken to start reining in the production of fossil fuels, the main driver of climate change.

The administration should release permits for drilling on federal lands, the lobby urged, and push ahead with leasing more tracts for offshore oil and development. The A.P.I., which condemned the invasion, also called on President Biden to accelerate permits for energy infrastructure and to roll back legal and regulatory uncertainty — industry speak for getting rules and lawsuits out of the way.

The crisis “has the given industry a great talking point,” said Kathy Hipple, a finance professor at the MBA in Sustainability program at Bard College and a research fellow at the Ohio River Valley Institute, a nonprofit think tank that focuses on oil and gas. But the industry misses the point that “we’re overly dependent on fossil fuels,” she said.

For one, experts are in agreement that nations around the world need to stop approving new coal-fired power plants, and new oil and gas fields, to avert the most catastrophic effects of climate change, Professor Hipple said. “Does anyone want to continue to be dependent on oligarchs in Russia, Saudi Arabia, Canada’s oil, a handful of private companies in the United States? To my mind, that’s not resilient,” she said.

Environmental groups criticized the industry’s logic. “It’s pretty rich for the oil and gas industry to talk about how reliable fossil fuels are when any big storm that happens, any time a war pops up, their reliability is thrown into question,” said Nathaniel Stinnett, founder and executive director of the Environmental Voter Project, a group that mobilizes voters in elections. “Wars aren’t fought over solar energy. You don’t see these huge price spikes in clean energy,” he said.

Some Republican lawmakers began to echo the oil and gas industry’s demands.

“It’s now clearer than ever what is at stake when anti-American energy policies make us and Europe more dependent on Russian oil and natural gas,” said Representative Cathy McMorris Rodgers, a Republican from Washington State and the Republican leader of the House Committee on Energy and Commerce. “I continue to urge President Biden to restore America’s energy dominance. It’s our most powerful weapon against Putin,” she said.

Mr. Biden’s attempts to quell concerns, promising that his administration will do everything it can to secure energy independence and “limit the pain the American people are feeling at the gas pump,” have fallen on deaf ears.

“You need to do much more. You need to get your boot off the neck of American energy producers,” Dan Sullivan, a Republican senator from Alaska said in a video response. The administration, he said, should revive the Keystone XL pipeline, for example — the embattled project that would have carried petroleum from Canadian tar sands to Nebraska — and resume issuing drilling leases in the Arctic National Wildlife Refuge, one of the largest tracts of untouched wilderness in the United States.

The oil and gas lobby has been less vocal about putting sanctions on Russia’s oil and gas capacity itself. In fact, even as the United States and Western Europe have imposed other economic sanctions, and Germany has put Russia’s Nord Stream 2 gas pipeline on hold, the Biden administration has so far held back on measures that directly affect Russian energy companies, instead focusing on banks, as well as government officials and their families.

Some of the industry’s biggest drillers, including Shell, BP and Exxon Mobil, are involved in oil and gas projects within Russia.

Aseem Prakash, a political science professor and founding director of the Center for Environmental Politics at the University of Washington, said continued pressure from the climate community meant Mr. Biden was unlikely to backslide on major climate-related decisions, like his canceling of the Keystone pipeline.

“But there could be surreptitious rollbacks, like less aggressive measures in terms of oil or shale leases. And their rhetoric will have to be toned down,” he said, referring to the Biden administration. In places like Pennsylvania, for example, Democrats “simply cannot afford to say, ‘Oil prices are rising, but let’s not revive shale.’ That’s political suicide,” he said.

These changes weren’t just coming as a result of the Ukraine crisis, he added. Rising gas prices had already started to shift the picture months ago.

The larger worry, he said, was that climate “could also get completely shoved off the agenda,” including hopes of passing an ambitious climate spending bill. “Everybody is talking Ukraine, everybody’s talking NATO,” he said, referring to the North Atlantic Treaty Organization, an alliance that Ukraine has sought to join over the objections of President Vladimir Putin of Russia. But the “climate problems aren’t going away,” Professor Prakash said.





#Environment | https://sciencespies.com/environment/us-oil-industry-uses-ukraine-invasion-to-push-for-more-drilling-at-home/

JUICE: What secrets lie beneath the icy surface of Jupiter’s moons?











Deep beneath the salty ocean, the seafloor is cracked. Hot gases from the layers below bubble into the water, sustaining colonies of microbial life that are eking out an existence far from the sunkissed surface.



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This may sound like a scene from the bottom of Earth’s vast oceans, but it’s actually a possible description of Europa – one of the icy moons orbiting Jupiter. And thanks to the upcoming Jupiter Icy Moons Explorer (JUICE) mission, we may finally have the opportunity to find out how accurate that description is.


Astrobiologists – scientists who look for signs of life beyond the confines of our planet – have long adhered to a simple mantra: follow the water. That’s because every living thing on Earth, from the tiniest bacterium to the mighty blue whale, needs liquid water to survive. While alien life without water may be possible, looking for that molecular marriage between hydrogen and oxygen is an excellent place to start.


In the hunt for H₂O, much has been made of the habitable zone – the narrow ring around a star where the temperature is just right for liquid water. Earth sits in this region, so the majority of our water neither freezes nor boils. But the habitable zone is an imperfect concept.


“At least five objects in the outer Solar System have sub-surface oceans,” says Dr Mark Fox-Powell, an astrobiologist at the Open University. All are far beyond the outer reaches of the traditional habitable zone. Three of these oceans can be found beneath the surfaces on a trio of Jupiter’s moons: Europa, Ganymede and Callisto. Jupiter has a habitable zone of its own. The required heat isn’t coming from the Sun, but from the gravity of Jupiter. It expands and contracts the moons, warming them up like squash balls.



An image showing the fractures across Europa's crust
Scores and fractures criss-cross Europa’s icy crust. The red-brown material is thought to be salt and sulphur compounds that have been modified by radiation © Science Photo Library

While we have been to the Jovian system many times, these moons have rarely been the main attraction. “The last time we were there studying them directly was with the Galileo spacecraft in the 1990s,” says Fox-Powell. Instead, the focus has tended to fall on the giant planet itself. But now there’s JUICE, a dedicated mission heading for its icy satellites.


Read more about Jupiter:


The spacecraft


At the heart of the JUICE mission is a spacecraft that’s been built by the European Space Agency (ESA). It bears a slight resemblance to a giant bird, with solar panel wings stretching out on either side of the spacecraft’s main body. The sunlight at Jupiter is 30 times dimmer than the light that reaches Earth, so the panels need to be big. They cover an area equal to 85m², or about half the size of a volleyball court.


Its three-metre-diameter antenna will send the data JUICE collects back to mission control, although it will take almost two hours to travel the more than half a billion kilometres to Earth.



A scale model of the RIME antenna undergoes testing at the Hertz facility in the Netherlands © ESA/ M Cowan
A scale model of the RIME antenna undergoes testing at the Hertz facility in the Netherlands © ESA/ M Cowan

ESA had been working towards launching JUICE in 2022 until the coronavirus pandemic hit. Instead of the planned liftoff, this coming year will now see frantic activity as ESA scrambles to claw back the time lost during lockdown, and make the final preparations needed to ready the landmark mission for its rescheduled launch in 2023.


The original plan was for JUICE to take a convoluted route, involving five flybys of Earth, Venus and Mars to use the planets’ gravitational might to slingshot the spacecraft towards Jupiter, a journey that was set to take 7.5 years. ESA has yet to reveal exact details of the new timeline, but JUICE should arrive at Jupiter at the start of the 2030s. Once there, it will spend at least three years exploring Europa, Ganymede and Callisto. It will be joined by NASA’s Europa Clipper mission, currently scheduled for launch in 2024 and arrival in April 2030.


The moons of Jupiter


We’ve known about these moons for a long time. Along with Io – the most volcanically active place in the Solar System – Europa, Ganymede and Callisto make up the so-called ‘Galilean moons’, first seen by the Italian astronomer Galileo at the start of the 17th Century.


Of the trio that JUICE will focus on, Europa tends to steal the limelight. “It’s definitely the poster child of the Galilean moons,” says Fox-Powell. That’s because beneath its icy crust sits an ocean that contains more liquid water than all of Earth’s seas, lakes and rivers combined. If there’s life swimming around in our oceans, could the same be true of Europa?


Part of the problem is that the ocean is hiding beneath a thick, icy surface. “We can’t access it directly,” says Fox-Powell. Thankfully, scientists think the icy crust and the water are interacting, a bit like the molten rock beneath Earth’s surface that breaks through during volcanic activity. “It means we can use material on the surface to study the oceans indirectly,” Fox-Powell says.



Ice volcanoes on Europa, illustration. Europa may have small ice volcanoes where warm water from deep beneath the icy crust makes its way to the surface, erupting like hot springs or geysers.
Plumes of water from the ocean below often erupt through Europa’s icy surface, as illustrated here. © Science Photo Library

We may even be able to collect a sample of that material, despite JUICE being unable to land on Europa. The spacecraft is carrying 10 high-precision instruments to Jupiter, including the Particle Environment Package (PEP). “It’s designed to study dust and other molecules that have been kicked up from the surface,” says Fox-Powell. “It’s not impossible that, if that material came from the oceans, it could contain molecules that are indicative of life.”


If there are organisms in Europa’s oceans, then they’ll need a source of energy. Hidden beneath the icy crust, they can’t get that energy from the Sun. Fox-Powell sees two potential options. The Jovian system is an environment flooded with intense levels of radiation as Jupiter’s magnetic field slings and funnels high-energy particles around.


“Any ocean material that ends up on the surface is going to be irradiated,” Fox-Powell says. That changes the chemistry of the ice. One likely scenario is that the radiation is breaking water into hydrogen and oxygen, with that oxygen potentially seeping back down into the ocean below. Other potential by-products include compounds containing the element sulphur. “On Earth, they’re known to support microbial life,” says Fox-Powell. JUICE will help us to learn more about that ocean-surface boundary and to what extent the conditions are suitable for biology.


Alternatively, life may have colonised the ocean floor. On Earth, there are whole communities of organisms that thrive on the seabed without any sunlight whatsoever. The source of their energy is hydrothermal vents – cracks in the boundary between the ocean and Earth’s hot interior. JUICE could help us see how geologically active Europa’s interior is.


An opportunity to survey Callisto


While Europa grabs the lion’s share of public attention, it’s not JUICE’s main target. The mission will only fly by Europa twice but will buzz past Callisto on 12 occasions. Callisto is the outermost of the four Galilean moons, so is least affected by Jupiter’s gravity and radiation. In contrast to Europa, whose surface is constantly reshaped by material welling up from beneath the ice, Callisto has the oldest surface in the Solar System. Unchanged for billions of years, it’s pockmarked by more impact craters than any other body orbiting the Sun.


Astronomers suspect that a 200km-deep ocean lies beneath Callisto’s ancient surface. This is where JUICE’s Radar for Icy Moons Exploration (RIME) instrument will come into its own. It will transmit radio waves that can penetrate the icy shells of the Galilean moons down to a depth of around nine kilometres. From the way the radio waves are reflected back, we should be able to learn more about the moons’ internal structures.


Another approach will be provided by the Gravity and Geophysics of Jupiter and Galilean Moons (3GM) instrument. It will measure the gravitational fields of Callisto and the other icy moons, which will reveal how different layers of material – including water – are stacked up inside them.


JUICE will also use Callisto for a leg-up. Mission controllers will use the gravity of the moon to increase the spacecraft’s inclination by about 30° so it can get a better look at Jupiter’s polar regions – the source of Jupiter’s vast and intense magnetic field.


Looking for magnetic fields


It is magnetism that determined where JUICE will spend the bulk of its time: Ganymede. Along with a dozen fly-bys, the spacecraft will also go into orbit around Ganymede and stay there for eight months. It will be the first time that a spacecraft from Earth has orbited a moon other than our own.


“Ganymede is the most exciting body in the Solar System,” says Prof Michele Dougherty, from Imperial College London. For one thing, it’s bigger than any other moon. In fact, it’s bigger than the dwarf planet Pluto and the planet Mercury. Like Europa, it’s also thought to have a sub-surface ocean that contains more water than we have on Earth.


Yet it’s Ganymede’s magnetism that’s the main attraction. It’s unique among the moons of the Solar System for having a magnetic field of its own. Dougherty is the principal investigator for J-MAG – an instrument on JUICE for measuring magnetic fields. J-MAG is located at the end of a 10.6m-long boom to keep it away from magnetic interference from the main spacecraft. Its sensitive electronics are locked inside a lead-lined vault to protect them from Jupiter’s intense radiation.



Auroral activity on Ganymede holds clues as to the magnetic influence of Jupiter © NASA/ ESA
Auroral activity on Ganymede holds clues as to the magnetic influence of Jupiter © NASA/ ESA

Dougherty wants to measure Ganymede’s magnetic field in detail, including how it interacts with Jupiter’s own magnetic field. Astronomers using the Hubble Space Telescope have spotted auroral activity on Ganymede. The equivalent of the northern and southern lights on Earth, the auroras should wobble around Ganymede’s poles due to the influence of Jupiter’s magnetism.


That they don’t, suggests a sub-surface ocean of salty water on Ganymede that’s conducting electricity and counter-balancing Jupiter’s magnetic might. Studying Ganymede’s magnetic field could provide further clues about the size and nature of this ocean. In turn, that could help us understand if it’s a place that may be home to alien life.


Separating Ganymede’s magnetic field from Jupiter’s is far from straightforward, though, particularly given how much the planet dominates its surrounding satellites. “It’s like trying to find needles in a haystack,” Dougherty says, “but they’re changing size, shape and colour all the time.” Still, she’s confident the team can pull it off. The flybys will be used to practise, with the really important data coming once JUICE settles into orbit around Ganymede. “The results are going to be spectacular,” Dougherty says.


Is there life elsewhere in the Solar System?


If she’s right, it’ll be the crowning achievement at the end of a long and winding road. Dougherty was previously involved in another flagship spacecraft: the Cassini mission to Saturn. Discussions about JUICE began in earnest in 2008, when Cassini had already been at Saturn for four years.


It was one of Saturn’s moons – Enceladus – that made people sit up and take notice. “My team was instrumental in discovering that Enceladus has plumes of water vapour,” Dougherty says. Water from a sub-surface ocean was being spat out into space, showing that it’s possible to find water beyond the traditional habitable zone.


“The discoveries at Enceladus showed us that focusing on moons of the outer planets was a good thing to do.” Soon a plan was hatched to get a closer view of Jupiter’s icy moons. Not that it’s all been plain-sailing. At one point during the pandemic, with labs closed, Dougherty’s team was building parts of J-MAG on their kitchen tables. “Building an instrument is always stressful, but the pandemic took that stress to the next level,” she says.



A simplified mock-up of the JUICE spacecraft is used to carry out tests © Airbus/ Rolf Schwark
A simplified mock-up of the JUICE spacecraft is used to carry out tests © Airbus/ Rolf Schwark

That effort is all the more remarkable given that the team will eventually destroy all of that hard work. Sometime in 2034, the spacecraft is likely to run out of propellant. Without any fuel, scientists will no longer be able to manoeuvre it around the Jovian system. So the team will do what’s been done before with spacecraft like Cassini and the MESSENGER mission to Mercury: deliberately crash it.


By smacking into the surface of Ganymede, JUICE will provide one final experiment to see what this gargantuan moon is made of. Its days of exploring Jupiter’s icy moons will be over, but scientists will continue to pore over JUICE’s collection of valuable data for a long time afterwards. “In 20 years’ time, our understanding of these moons will be different,” says Fox-Powell. “JUICE is going to provide a real revolution.” It could, finally, tell us whether or not we’re alone in this vast and often surprising Solar System.


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#Space | https://sciencespies.com/space/juice-what-secrets-lie-beneath-the-icy-surface-of-jupiters-moons/