NBC News reports that in various parts of America, "States that had committed to using contact tracing apps or expressed interest are now backing away from those claims." The few states that have rolled them out have seen only tepid responses. And there are no indications of any momentum for the apps at a national level... A survey of state health officials from Business Insider this week showed that only three states — Alabama, North Dakota and South Carolina — said they were going to use the software provided by Apple and Google. The number hasn't grown since the same three states reported interest last month, and none has launched an app with the Google-Apple software...

Even the World Health Organization has piled on. "Digital tools do not replace the human capacity needed to do contact tracing," WHO Director-General Tedros Adhanom Ghebreyesus said at a briefing this week, adding that more evidence was needed and that the WHO would convene experts to share information...

A handful of states — North Dakota, South Dakota and Utah — launched apps without the support of Apple and Google, but none saw widespread adoption. More states, including Washington, have considered doing so or have launched test versions, and it's possible that apps will gain momentum closer to the fall, when they might be taken up by more employers, schools and universities and at related football games.
Two months ago Google and Apple announced a joint project to build a contact-tracing app -- which was supported by the governor of America's most populous state, California. But now a spokesperson for California's public health department tells NBC News that the state isn't currently using any apps or cellphone tracking technology.

"Most of the contact tracing work (notifying people who have been in close contact with an infected person to prevent the disease from spreading to others) can be done by phone, text, email and chat."

An anonymous reader quotes a report from Ars Technica: On May 29, President Trump said his administration would take immediate action to withdraw the U.S. from the World Health Organization. "Because they have failed to make the requested and greatly needed reforms, we will be today terminating our relationship with the World Health Organization, and redirecting those funds to other worldwide and deserving, urgent global public health needs," Trump said at the time, while criticizing the WHO's response to the coronavirus pandemic and claiming that "China has total control" over the United Nations agency.

But now, two weeks later, there's nothing to indicate that Trump has followed through on his plan. In an article yesterday titled "U.S. hasn't taken action to withdraw from WHO despite Trump pledge," The Hill wrote that "no steps toward a formal withdrawal have been taken," and that "a WHO spokesman told The Hill that the agency had received no formal notification that the United States would withdraw." Another article yesterday in Stat, a health news website, said that "none of the levers that would need to be pulled to follow through on [Trump's WHO] decision has been pulled." For example, the Trump administration has "not paid outstanding financial obligations to the WHO, a step that would be required before the United States could pull out under a joint resolution signed by Congress," the article said. These reports follow a Vanity Fair article published Monday that describes "the secret plan to unwithdraw from the WHO after Trump's 'bizarre,' 'ruinous' exit." The article continued:

"Now, Vanity Fair has learned, secret negotiations aimed at reversing Trump's decision have begun between [U.S.] Ambassador [Andrew] Bremberg and the WHO's director general, Dr. Tedros Adhanom Ghebreyesus. A phone call Saturday between the two men resulted in a possible framework agreement to restore the relationship, which the U.S. diplomatic corps views as essential to the global fight against coronavirus and myriad other public health issues.

"The framework would allow for both increased scrutiny of China's conduct and an independent review of the WHO's performance in the first six months of the outbreak. And discussions continue over whether the WHO would exert pressure on China to turn over original samples of the live virus and allow its scientists to be interviewed regarding the virus's origins. 'It's fair to say the US is not out of WHO, and negotiations are ongoing to address concerns and hopefully walk back from this decision,' said an official who participated in a call with G7 partners, an alliance of countries with advanced economies, where this information was shared."

Sexual activity among young American men has declined sharply since 2000, with nearly a third reporting no sex with a partner in the prior year, according to a survey study published on Friday that suggests social media and electronic gaming might be filling the void. Reuters reports: The survey found that from 2000 to 2018, nearly one in three U.S. men aged 18 to 24 reported no sexual activity in the past year. Lack of sexual activity, or sexual inactivity, was also on the rise among men and women aged 25 to 34 years during the survey period, the report in the journal JAMA Network Open found. Possible reasons for the decline in sexual frequency may also include stress of juggling work and intimate relationships, as well as the prevalence of other forms of solo entertainment.

"There are now many more choices of things to do in the late evening than there once were and fewer opportunities to initiate sexual activity if both partners are engrossed in social media, electronic gaming, or binge watching," Jean Twenge, from the department of psychology in San Diego State University said in an editorial accompanying the report.

Scientists combed through nearly 30 years of earthquake data to probe huge and mysterious objects near the Earth's core. From a report: Scientists have discovered a vast structure made of dense material occupying the boundary between Earth's liquid outer core and the lower mantle, a zone some 3,000 kilometers (1,864 miles) beneath our feet. The researchers used a machine learning algorithm that was originally developed to analyze distant galaxies to probe the mysterious phenomenon occurring deep within our own planet, according to a paper published on Thursday in Science. One of these enormous anomalies, located deep under the Marquesas Islands, had never been detected before, while another structure beneath Hawaii was found to be much larger than previously estimated.

Scientists led by Doyeon Kim, a seismologist and postdoctoral fellow at the University of Maryland, fed seismograms captured from hundreds of earthquakes that occurred between 1990 to 2018 into an algorithm called Sequencer. While seismological studies tend to focus on relatively small datasets of regional earthquake activity, Sequencer allowed Kim and his colleagues to analyze 7,000 measurements of earthquakes -- each with a magnitude of at least 6.5 -- that shook the subterranean world under the Pacific Ocean within the past three decades. "This study is very special because, for the first time, we get to systematically look at such a large dataset that actually covers more or less the entire Pacific basin," Kim said in a call. Though scientists have previously mapped out structures deep inside Earth, this study presents a rare opportunity to "bring everything in together and try to explain it in a global context," he noted.

NASA has awarded Astrobotic of Pittsburgh $199.5 million to deliver NASA's Volatiles Investigating Polar Exploration Rover (VIPER) to the Moon's South Pole in late 2023. From a report: The water-seeking mobile VIPER robot will help pave the way for astronaut missions to the lunar surface beginning in 2024 and will bring NASA a step closer to developing a sustainable, long-term presence on the Moon as part of the agency's Artemis program. "The VIPER rover and the commercial partnership that will deliver it to the Moon are a prime example of how the scientific community and U.S. industry are making NASA's lunar exploration vision a reality," said NASA Administrator Jim Bridenstine. "Commercial partners are changing the landscape of space exploration, and VIPER is going to be a big boost to our efforts to send the first woman and next man to the lunar surface in 2024 through the Artemis program."

VIPER's flight to the Moon is part of NASA's Commercial Lunar Payload Services (CLPS) initiative, which leverages the capabilities of industry partners to quickly deliver scientific instruments and technology demonstrations to the Moon. As part of its award, Astrobotic is responsible for end-to-end services for delivery of VIPER, including integration with its Griffin lander, launch from Earth, and landing on the Moon.

Writing today in the journal Science, researchers report a startling discovery: After collecting rainwater and air samples for 14 months, they calculated that over 1,000 metric tons of microplastic particles fall into 11 protected areas in the western U.S. each year. That's the equivalent of over 120 million plastic water bottles. Wired: To quantify just how bad the problem has become across the American West, the researchers used collectors in 11 national parks and protected areas, sampling both rain and air. Each had a "wet" bucket to collect rainwater, and a "dry" bucket to collect air. A sensor would detect rainfall and open up the "wet" bucket while closing the dry one. And vice versa when it's sunny out, so the dry bucket would collect microplastic particles carried on the wind while the wet bucket stayed shut. The researchers also modeled where each particular storm they collected rain from had originated, looking at the size of the cities it traveled through before dumping water, and microplastics, into the wet bucket.

Overall, they found that a stunning 98 percent of samples collected over a year contained microplastic particles. On average, 4 percent of captured atmospheric particulates were actually synthetic polymers. The particles that fell in rain were larger than those deposited by wind -- lighter particles are more easily caught up in air currents. Microfibers, from sources like polyester clothing, made up 66 percent of the synthetic material in wet samples and 70 percent in dry samples. Plus, the team wasn't able to count clear or white particles and fibers with their equipment, so their tally is likely conservative.

New submitter gam shares an announcement from MIT: Standing by its commitment to provide equitable and open access to scholarship, MIT has ended negotiations with Elsevier for a new journals contract. Elsevier was not able to present a proposal that aligned with the principles of the MIT Framework for Publisher Contracts.

Developed by the MIT Libraries in collaboration with the Ad Hoc Task Force on Open Access to MIT's Research and the Committee on the Library System in October 2019, the MIT Framework is grounded in the conviction that openly sharing research and educational materials is key to the Institute's mission of advancing knowledge and bringing that knowledge to bear on the world's greatest challenges. It affirms the overarching principle that control of scholarship and its dissemination should reside with scholars and their institutions, and aims to ensure that scholarly research outputs are openly and equitably available to the broadest possible audience, while also providing valued services to the MIT community. More than 100 institutions, ranging from multi-institution consortia to large research universities to liberal arts colleges, decided to endorse the MIT Framework in recognition of its potential to advance open scholarship and the public good. "We hope to be able to resume productive negotiations if and when Elsevier is able to provide a contract that reflects our community's needs and values and advances MIT's mission," said Chris Bourg, director of the MIT Libraries. "In the meantime, we will continue to use the framework to pursue new paths to achieving open access to knowledge..."

On board the International Space Station since May 2018 is a mini-fridge-size facility called the Cold Atom Lab (CAL), capable of chilling atoms in a vacuum down to temperatures one ten billionth of a degree above absolute zero. It is, for all intents and purposes, one of the coldest spots in the known universe. And according to a new study published in Nature, scientists have just used it to create a rare state of matter for the first time ever in space. From a report: Bose-Einstein condensates, sometimes called the fifth state of matter, are gaseous clouds of atoms that stop behaving like individual atoms and start to behave like a collective. BECs, as they're often called, were first predicted by Albert Einstein and Satyendra Nath Bose over 95 years ago, but they were first observed in the lab by scientists just 25 years ago. The general idea when making a BEC is to inject atoms (in the case of CAL, rubidium and potassium) into an ultra-cold chamber to slow them down. A magnetic trap is then created in the chamber with an electrified coil, which is used along with lasers and other tools to move the atoms into a dense cloud. At this point the atoms "kind of blur into one another," says David Aveline, a physicist at NASA's Jet Propulsion Laboratory, and the lead author of the new study.

To run experiments using a BEC, you need to turn down or release the magnetic trap. The cloud of crowded atoms will expand, which is useful because BECs need to stay cold, and gases tend to cool off as they expand. But if the atoms in a BEC get too far apart, they no longer behave like a condensate. This is where the microgravity of low Earth orbit comes into play. If you try to increase the volume on Earth, says Aveline, gravity will just pull the atoms in the center of the BEC cloud down to the bottom of the trap until they spill out, distorting the condensate or ruining it entirely. But in microgravity, the tools in the CAL can hold the atoms together even as the trap's volume increases. That makes for a longer-lived condensate, which in turn allows scientists to study it longer than they could on Earth (this initial demonstration ran for 1.118 seconds, although the goal is to be able to detect the cloud for up to 10 seconds). Though only a first step, the CAL experiment could one day allow BECs to form the basis of ultra-sensitive instruments that detect faint signals from some of the universe's most mysterious phenomena, like gravitational waves and dark energy. From a more practical perspective, Aveline believes the team's work could pave the way for better inertial sensors. "The applications range from accelerometers and seismometers to gyroscopes," he says.

The James Webb Space Telescope, NASA's follow-on instrument to the wildly successful Hubble Space Telescope, will not meet its current schedule of launching in March 2021, according to the chief of NASA's science programs. Ars Technica reports: "We will not launch in March," said Thomas Zurbuchen, the space agency's associate administrator for science. "Absolutely we will not launch in March. That is not in the cards right now. That's not because they did anything wrong. It's not anyone's fault or mismanagement." Zurbuchen made these comments at a virtual meeting of the National Academies' Space Studies Board. He said the telescope was already cutting it close on its schedule before the COVID-19 pandemic struck the agency and that the virus had led to additional lost work time.

"This team has stayed on its toes and pushed this telescope forward at the maximum speed possible," he said. "But we've lost time. Instead of two shifts fully staffed, we could not do that for all the reasons that we talk about. Not everybody was available. There were positive cases here and there. And so, perhaps, we had only one shift." NASA and the telescope's prime contractor, Northrop Grumman, are evaluating the schedule going forward. This will include an estimate of when operations can completely return to normal -- Zurbuchen said telescope preparation and testing activities are nearing full staffing again -- and set a new date for a launch. This schedule review should conclude in July. "I'm very optimistic about this thing getting off the launch pad in 2021," Zurbuchen said. "Of course, there is still a lot of mountain to climb."

Software developer Danny Bittman tweeted about how he's convinced that his eyesight was damaged from wearing a VR headset for hours a day. The BBC reports: Danny Bittman, who has worked as a virtual reality developer for four years, suggested it could have affected his eyesight. "Just had my first eye doctor visit in three years. Now I'm very worried about my future VR use. I have a new eye convergence problem that acts like dyslexia. The doc, a headset owner, is convinced my VR use caused this. He said "these glasses we usually prescribe to 40-year-olds," he tweeted. He went on to describe the problem: "My eyes jump when I read things like a screen or books. I've always had a small level of this but it's greatly intensified now. It's also linked to headaches and vertigo."

He said that the issue was about "prolonged use," and admitted that he could spend up to six hours a day wearing a headset, split into 30-minute sessions. Ceri Smith-Jaynes, from the Association of Optometrists, told the BBC: "We currently do not have any reliable evidence that VR headsets cause permanent deterioration in eyesight in children or adults. There have been some studies looking into the effects of short-term use of VR headsets only; these did not reveal a deterioration in eyesight. "However, some people do suffer from temporary symptoms such as nausea, dry, irritable eyes, headache or eyestrain." But she did have some advice about usage: "If you spend all day in VR without a break, you'll need time to readjust to the light and the different visual environment of the real world. I would suggest taking a five-to-ten minute break each hour, using that time to move about, blink and look out of a window, or take a short walk.

Representation theory was initially dismissed. Today, it's central to much of mathematics. From a report: When representation theory emerged in the late 19th century, many mathematicians questioned its worth. In 1897, the English mathematician William Burnside wrote that he doubted that this unorthodox perspective would yield any new results at all. "Basically what [Burnside was] saying is that representation theory is useless," said Geordie Williamson of the University of Sydney in a 2015 lecture. More than a century since its debut, representation theory has served as a key ingredient in many of the most important discoveries in mathematics. Yet its usefulness is still hard to perceive at first. "It doesn't seem immediately clear that this is a reasonable thing to study," said Emily Norton of the Technical University of Kaiserslautern in Germany.

Representation theory is a way of taking complicated objects and "representing" them with simpler objects. The complicated objects are often collections of mathematical objects -- like numbers or symmetries -- that stand in a particular structured relationship with each other. These collections are called groups. The simpler objects are arrays of numbers called matrices, the core element of linear algebra. While groups are abstract and often difficult to get a handle on, matrices and linear algebra are elementary. "Mathematicians basically know everything there is to know about matrices. It's one of the few subjects of math that's thoroughly well understood," said Jared Weinstein of Boston University.

An anonymous reader quotes a report from the BBC: Babylon Health has acknowledged that its GP video appointment app has suffered a data breach. The firm was alerted to the problem after one of its users discovered he had been given access to dozens of video recordings of other patients' consultations. A follow-up check by Babylon revealed a small number of further UK users could also see others' sessions. The firm said it had since fixed the issue and notified regulators. Babylon allows its members to speak to a doctor, therapist or other health specialist via a smartphone video call and, when appropriate, sends an electronic prescription to a nearby pharmacy. It has more than 2.3 million registered users in the UK. "On the afternoon of Tuesday June 9 we identified and resolved an issue within two hours whereby one patient accessed the introduction of another patient's consultation recording," it said in statement. "Our investigation showed that three patients, who had booked and had appointments today, were incorrectly presented with, but did not view, recordings of other patients' consultations through a subsection of the user's profile within the Babylon app."

Researchers around the world are developing more than 135 vaccines against the coronavirus. Vaccines typically require years of research and testing before reaching the clinic, but scientists are racing to produce a safe and effective vaccine by next year. The New York Times: Work began in January with the deciphering of the SARS-CoV-2 genome. The first vaccine safety trials in humans started in March, but the road ahead remains uncertain. Some trials will fail, and others may end without a clear result. But a few may succeed in stimulating the immune system to produce effective antibodies against the virus. The story outlines the status of all the vaccines that have reached trials in humans, along with a selection of promising vaccines still being tested in cells or animals. The closest to developing the vaccine currently is a joint collaboration between the British-Swedish company AstraZeneca and the University of Oxford, and their vaccine is based on a chimpanzee adenovirus called ChAdOx1. The vaccine has gone through Phase I testing and is beginning Phase II/III testing in England and Brazil. Supported by Operation Warp Speed, the project may deliver emergency vaccines by October.

An anonymous reader quotes a report from IEEE Spectrum: Flat solar panels still face big limitations when it comes to making the most of the available sunlight each day. A new spherical solar cell design aims to boost solar power harvesting potential from nearly every angle without requiring expensive moving parts to keep tracking the sun's apparent movement across the sky. The spherical solar cell prototype designed by Saudi researchers is a tiny blue sphere that a person can easily hold in one hand like a ping pong ball. Indoor experiments with a solar simulator lamp have already shown that it can achieve between 15 percent and 100 percent more power output compared with a flat solar cell with the same total surface area, depending on the background materials reflecting sunlight into the solar cells. The research group hopes its nature-inspired design can fare similarly well in future field tests in many different locations around the world.

Testing with the solar simulator lamp showed that the spherical solar cell provided 24 percent more power output over a traditional flat solar cell upon immediate exposure to sunlight. That power advantage jumped to 39 percent after both types of solar cells had begun to heat up and suffered some loss in power efficiency -- an indication that the spherical shape may have some advantages in dissipating heat. The spherical solar cell also delivered about 60 percent more power output than its flat counterpart when both could collect only scattered sunlight under a simulated roof rather than receiving direct sunlight. Additional experiments with different reflective backgrounds -- including an aluminum cup, aluminum paper, white paper, and sand -- showed that the hexagonal aluminum cup background helped the spherical solar cell outperform the flat solar cell by 100 percent in terms of power output. The new work is detailed in a paper submitted for review to the journal MRS Communications.

An anonymous reader quotes a report from Phys.Org: Our lungs, bones, blood vessels and other major organs are made up of cells, and one way our bodies keep us healthy is by using protein messengers known as ligands that bind to receptors on the surfaces of cells to regulate our biological processes. When those messages get garbled, it can make us ill with a host of different diseases. Now a team led by Stanford bioengineer and department chair Jennifer Cochran has tweaked one ligand in slightly different ways to produce two startlingly different results. One set of alterations caused neuronal cells to regenerate, while different tweaks to the same protein inhibited lung tumor growth. The experiments her team described in the Proceedings of the National Academy of Sciences were performed on rat and human cells or in mice that model actual diseases and are still far from being tested in humans. But the results show how scientists are becoming increasingly adept at tinkering with the body's protein-based control mechanisms to help vital organs heal themselves.

California counties, including Los Angeles County, could decide to reopen movie theaters as early as Friday. The Los Angeles Times reports: Each local health officer has the authority to decide whether to move forward with relaxing restrictions on reopening theaters. While the state provides guidance on how businesses can reopen, counties decide when they occur. The new rules would limit the number of guests in a movie theater to 25% of theater capacity or a maximum of 100 attendees, whichever is lower. Also, theaters would need to implement a reservation system to limit the number of attendees entering the theater at a time when possible. "Designate arrival times as part of reservations, if possible so that customers arrive at and enter the theater in staggered groups," the state's rules say.

To keep guests six feet away from others, theaters are to close or otherwise remove seats from use, which may require seating every other row or blocking off seats in a checkerboard style, in which no one is sitting directly behind other patrons. The rules would ask patrons to wear face coverings when not eating or drinking. Staff would need to be available to help usher people before the show begins and at its conclusion to reduce crowding when entering or exiting. The guidelines also suggest using disposable or washable seat covers in theaters, "particularly on porous surfaces that are difficult to properly clean. Discard and replace seat covers between each use," the guidelines say.

Los Angeles, San Diego, Orange, Riverside, San Bernardino and Ventura are among 51 California counties that will be given the option by the state to allow movie theaters to reopen. All but seven of California's 58 counties have filed attestation paperwork to reopen their economies at an accelerated pace. Six of the counties that have not done so are in the San Francisco Bay Area -- Alameda, Contra Costa, Marin, San Francisco, San Mateo and Santa Clara -- and the seventh is Imperial County east of San Diego, which is facing a bad outbreak. Deadline notes that while some independently owned cinemas could open their doors again, "many notable chains won't."

Not only do movie theaters need more time to prep, but many have paused their leases with landlords. "Also, while a 30%-50% capacity auditorium level is doable financially for most theater owners, a 25% cap is stretching it for some," the report adds. "Chains in California we hear aren't reopening Friday include AMC, Regal, Cinemark (which has outlined a three-phase approach beginning June 19 in Dallas), Alamo Drafthouse, Arclight Cinemas, Laemmle, Cinepolis and Landmark."

Beijing dismissed as "ridiculous" a Harvard Medical School study of hospital traffic and search engine data that suggested the new coronavirus may already have been spreading in China last August, and scientists said it offered no convincing evidence of when the outbreak began. From a report: The research, which has not been peer-reviewed by other scientists, used satellite imagery of hospital parking lots in Wuhan -- where the disease was first identified in late 2019 -- and data for symptom-related queries on search engines for things such as "cough" and "diarrhea." The study's authors said increased hospital traffic and symptom search data in Wuhan preceded the documented start of the SARS-CoV-2 pandemic in December 2019.

"While we cannot confirm if the increased volume was directly related to the new virus, our evidence supports other recent work showing that emergence happened before identification at the Huanan Seafood market (in Wuhan)," they said. Paul Digard, an expert in virology at the University of Edinburgh, said that using search engine data and satellite imagery of hospital traffic to detect disease outbreaks "is an interesting idea with some validity." But he said the data were only correlative and -- as the Harvard scientists noted -- cannot identify cause.

A top expert at the World Health Organization on Tuesday walked back her earlier assertion that transmission of the coronavirus by people who do not have symptoms is "very rare." From a report: Dr. Maria Van Kerkhove, who made the original comment at a W.H.O. briefing on Monday, said that it was based on just two or three studies and that it was a "misunderstanding" to say asymptomatic transmission is rare globally. "I was just responding to a question, I wasn't stating a policy of W.H.O. or anything like that," she said. Dr. Van Kerkhove said that the estimates of transmission from people without symptoms come primarily from models, which may not provide an accurate representation. "That's a big open question, and that remains an open question," she said.

Scientists had sharply criticized the W.H.O. for creating confusion on the issue, given the far-ranging public policy implications. Governments around the world have recommended face masks and social distancing measures because of the risk of asymptomatic transmission. A range of scientists said Dr. Van Kerkhove's comments did not reflect the current scientific research. "All of the best evidence suggests that people without symptoms can and do readily spread SARS-CoV-2, the virus that causes Covid-19," scientists at the Harvard Global Health Institute said in a statement on Tuesday.

An anonymous reader quotes a report from PBS NewsHour: The head of the World Health Organization warned that the coronavirus pandemic is worsening globally, even as the situation in Europe is improving. At a press briefing on Monday, Tedros Adhanom Ghebreyesus noted that about 75% of cases reported to the U.N. health agency on Sunday came from 10 countries in the Americas and South Asia. He noted that more than 100,000 cases have been reported on nine of the past 10 days -- and that the 136,000 cases reported Sunday was the biggest number so far. Tedros said most countries in Africa are still seeing an increase in cases, including in new geographic areas even though most countries on the continent have fewer than 1,000 cases. "At the same time, we're encouraged that several countries around the world are seeing positive signs," Tedros said. "In these countries, the biggest threat now is complacency." There was some good news to come from the media briefing. "From the data we have, it still seems to be rare that an asymptomatic person actually transmits onward to a secondary individual," said Maria Van Kerkhove on Monday. "We have a number of reports from countries who are doing very detailed contact tracing. They're following asymptomatic cases, they're following contacts and they're not finding secondary transmission onward. It is very rare -- and much of that is not published in the literature," she said. "We are constantly looking at this data and we're trying to get more information from countries to truly answer this question. It still appears to be rare that an asymptomatic individual actually transmits onward."

Tedros also dedicated time to addressing protests across the globe fighting against police brutality and systemic racism. "WHO fully supports equality and the global movement against racism," Tedros said during the briefing. "We reject discrimination of all kinds. We encourage all those protesting around the world to do so safely."

According to a study published in the journal Nature Astronomy, the orbit of Saturn's moon Titan is expanding at a rate about 100 times faster than expected. "The research suggests that Titan was born much closer to Saturn and migrated out to its current distance of 1.2 million kilometers (about 746,000 miles) over 4.5 billion years," reports Phys.Org. From the report: In the work detailed in the Nature Astronomy paper, two teams of researchers each used a different technique to measure Titan's orbit over a period of 10 years. One technique, called astrometry, produced precise measurements of Titan's position relative to background stars in images taken by the Cassini spacecraft. The other technique, radiometry, measured Cassini's velocity as it was affected by the gravitational influence of Titan. "By using two completely independent data sets -- astrometric and radiometric -- and two different methods of analysis, we obtained results that are in full agreement," says the study's first author, Valery Lainey formerly of JPL (which Caltech manages for NASA), now of Paris Observatory, PSL University. Lainey worked with the astrometry team.

The results are also in agreement with a theory proposed in 2016 by Fuller, who predicted that Titan's migration rate would be much faster than standard tidal theories estimated. His theory notes that Titan is expected to gravitationally squeeze Saturn with a particular frequency that makes the planet oscillate strongly, similarly to how swinging your legs on a swing with the right timing can drive you higher and higher. This process of tidal forcing is called resonance locking. Fuller proposed that the high amplitude of Saturn's oscillation would dissipate a lot of energy, which in turn would cause Titan to migrate outward away from the planet at a faster rate than previously thought. Indeed, the observations both found that Titan is migrating away from Saturn at a rate of 11 centimeters per year, more than 100 times faster than previous theories predicted.