Science

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Whale songs have features of language, but whales may not be speaking

animal behavior, Biology, language, Science, whale song, whales / /
A group of sperm whales and remora idle near the surface of the ocean.

Whales use complex communication systems we still don’t understand, a trope exploited in sci-fi shows like Apple TV’s Extrapolations. That show featured a humpback whale (voiced by Meryl Streep) discussing Mahler’s symphonies with a human researcher via some AI-powered inter-species translation app developed in 2046.

We’re a long way from that future. But a team of MIT researchers has now analyzed a database of Caribbean sperm whales’ calls and has found there really is a contextual and combinatorial structure in there. But does it mean whales have a human-like language and we can just wait until Chat GPT 8.0 to figure out how to translate from English to Sperm-Whaleish? Not really.

One-page dictionary

“Sperm whales communicate using clicks. These clicks occur in short packets we call codas that typically last less than two seconds, containing three to 40 clicks,” said Pratyusha Sharma, a researcher at the MIT Computer Science and Artificial Intelligence Laboratory and the lead author of the study. Her team argues that codas are analogues of words in human language and are further organized in coda sequences that are analogues of sentences. “Sperm whales are not born with this communication system; it’s acquired and changes over the course of time,” Sharma said.

Seemingly, sperm whales have a lot to communicate about. Earlier observational studies revealed that they live a fairly complex social life revolving around family units forming larger structures called clans. They also have advanced hunting strategies and do group decision-making, seeking consensus on where to go and what to do.

Despite this complexity in behavior and relationships, their vocabulary seemed surprisingly sparse.

Sharma’s team sourced a record of codas from the dataset of the Dominica Sperm Whale Project, a long-term study on sperm whales that recorded and annotated 8,719 individual codas made by EC-1, a sperm whale clan living in East Caribbean waters. Those 8,719 recorded codas, according to earlier research on this database, were really just 21 coda types that the whales were using over and over.

A set of 21 words didn’t look like much of a language. “But this [number] is exactly what we found was not true,” Sharma said.

Fine-grained changes

“People doing those earlier studies were looking at the calls in isolation… They were annotating these calls, taking them out of context, shuffling them up, and then tried to figure out what kind of patterns were recurring,” Sharma explained. Her team, by contrast, analyzed the same calls in their full context, basically looking at entire exchanges rather than at separate codas. “One of the things we saw was fine-grained changes in the codas that other whales participating in the exchange were noticing and reacting to. If you looked at all these calls out of context, all these fine-grained changes would be lost; they would be considered noise,” Sharma said.

The first of those newly recognized fine-grained changes was termed “rubato,” borrowed from music, where it means introducing slight variations in the tempo of a piece. Communicating sperm whales could stretch or shrink a coda while keeping the same rhythm (where rhythm describes the spacing between the clicks in a coda).

The second feature the researchers discovered was ornamentation. “An ornament is an extra click added at the end of the coda. And when you have this extra click, it marks a critical point, and the call changes. It either happens toward the beginning or at the end of the call,” said Sharma.

The whales could individually manipulate rubato and ornamentation, as well as previously identified rhythm and tempo features. By combining this variation, they can produce a very large variety of codas. “The whales produce way more combinations of these features than 21—the information-carrying capacity of this system is a lot more capable than that,” Sharma said.

Her team identified 18 types of rhythm, three variants of rubato, five types of tempo, and an ability to add an ornament or not in the sperm whale’s communication system. That adds up to 540 possible codas, of which there are roughly 150 these whales frequently used in real life. Not only were sperm whales’ calls built with distinctive units at a coda level (meaning they were combinatorial), but they were compositional in that a call contained multiple codas.

But does that get us any closer to decoding the whale’s language?

“The combinatoriality at the word level and compositionality at the sentence level in human languages is something that looks very similar to what we found,” Sharma said. But the team didn’t determine whether meaning was being conveyed, she added. And without evidence of meaning, we might be barking up the wrong tree entirely.

Whale songs have features of language, but whales may not be speaking Read More »

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The first crew launch of Boeing’s Starliner capsule is on hold indefinitely

atlas v, Boeing, commercial crew, human spaceflight, NASA, Science, Space, starliner, united launch alliance / /

Pursuing rationale —

“NASA will share more details once we have a clearer path forward.”

–

Boeing's Starliner spacecraft on the eve of the first crew launch attempt earlier this month.

Enlarge / Boeing’s Starliner spacecraft on the eve of the first crew launch attempt earlier this month.

Miguel J. Rodriguez Carrillo/AFP via Getty Images

The first crewed test flight of Boeing’s long-delayed Starliner spacecraft won’t take off as planned Saturday and could face a longer postponement as engineers evaluate a stubborn leak of helium from the capsule’s propulsion system.

NASA announced the latest delay of the Starliner test flight late Tuesday. Officials will take more time to consider their options for how to proceed with the mission after discovering the small helium leak on the spacecraft’s service module.

The space agency did not describe what options are on the table, but sources said they range from flying the spacecraft “as is” with a thorough understanding of the leak and confidence it won’t become more significant in flight, to removing the capsule from its Atlas V rocket and taking it back to a hangar for repairs.

Theoretically, the former option could permit a launch attempt as soon as next week. The latter alternative could delay the launch until at least late summer.

“The team has been in meetings for two consecutive days, assessing flight rationale, system performance, and redundancy,” NASA said in a statement Tuesday night. “There is still forward work in these areas, and the next possible launch opportunity is still being discussed. NASA will share more details once we have a clearer path forward.”

Delays are nothing new for the Starliner program, but it’s not yet clear how this delay will compare to the spacecraft’s previous setbacks.

Software problems cut short an unpiloted test flight in 2019, forcing Boeing to fly a second demonstration mission. Starliner was on the launch pad when pre-flight checkouts revealed stuck valves in the spacecraft’s propulsion system in 2021. Boeing finally flew Starliner on a round-trip mission to the space station in May 2022. Concerns about Starliner’s parachutes and flammable tape inside the spacecraft’s crew cabin delayed the crewed test flight from last summer until this year.

Boeing aims to become the second company to fly astronauts to the space station under contract with NASA’s commercial crew program, following the start of SpaceX’s crew transportation service in 2020. Assuming a smooth crewed test flight, NASA hopes to clear the Starliner spacecraft for six-month crew rotation flights to the space station beginning next year.

In the doghouse

Engineers first noticed the helium leak during the first launch attempt for Starliner’s crewed test flight May 6, but managers did not consider it significant enough to stop the launch. Ultimately, a separate problem with a pressure regulation valve on the spacecraft’s United Launch Alliance (ULA) Atlas V rocket prompted officials to scrub the launch attempt.

NASA astronauts Butch Wilmore and Suni Williams were already strapped into their seats inside the Starliner spacecraft on the launch pad at Cape Canaveral Space Force Station, Florida, when officials ordered a halt to the May 6 countdown. Wilmore and Williams returned to their homes in Houston to await the next Starliner launch opportunity.

ULA returned the Atlas V rocket to its hangar, where technicians swapped out the faulty valve in time for another launch attempt May 17. NASA and Boeing pushed the launch date back to May 21, then to May 25, as engineers assessed the helium leak. The Atlas V rocket and Starliner spacecraft remain inside ULA’s Vertical Integration Facility to wait for the next launch opportunity.

Boeing engineers traced the leak to a flange on a single reaction control system thruster in one of four doghouse-shaped propulsion pods on the Starliner service module.

There are 28 reaction control system thrusters—essentially small rocket engines—on the Starliner service module. In orbit, these thrusters are used for minor course corrections and pointing the spacecraft in the proper direction. The service module has two sets of more powerful engines for larger orbital adjustments and launch-abort maneuvers.

The spacecraft’s propulsion system is pressurized using helium, an inert gas. The thrusters burn a mixture of toxic hydrazine and nitrogen tetroxide propellants. Helium is not combustible, so a small leak is not likely to be a major safety issue on the ground. However, the system needs sufficient helium gas to force propellants from their internal storage tanks to Starliner’s thrusters.

In a statement last week, NASA described the helium leak as “stable” and said it would not pose a risk to the Starliner mission if it didn’t worsen. A Boeing spokesperson declined to provide Ars with any details about the helium leak rate.

If NASA and Boeing resolve their concerns about the helium leak without requiring lengthy repairs, the International Space Station could accommodate the docking of Starliner through part of July. After docking at the station, Wilmore and Williams will spend at least eight days at the complex before undocking to head for a parachute-assisted, airbag-cushioned landing in the Southwestern United States.

After July, the schedule gets messy.

The space station has a busy slate of multiple visiting crew and cargo vehicles in August, including the arrival of a fresh team of astronauts on a SpaceX Dragon spacecraft and the departure of an outgoing crew on another Dragon. There may be an additional window for Starliner to dock with the space station in late August or early September before the launch of SpaceX’s next cargo mission, which will occupy the docking port Starliner needs to use. The docking port opens up again in the fall.

ULA also has other high-priority missions it would like to launch from the same pad needed for the Starliner test flight. Later this summer, ULA plans to launch a US Space Force mission; it will be the last mission to use an Atlas V rocket. Then, ULA aims to launch the second demonstration flight of its new Vulcan Centaur rocket—the Atlas V’s replacement—as soon as September.

The first crew launch of Boeing’s Starliner capsule is on hold indefinitely Read More »

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Nova explosion visible to the naked eye expected any day now

astronomy, astrophysics, nova, Science, white dwarf / /
Image of a blue sphere, surrounded by blue filaments, and enclosed in a partial sphere of pink specks.s

Enlarge / Aftermath of a nova at the star GK Persei.

When you look at the northern sky, you can follow the arm of the Big Dipper as it arcs around toward the bright star called Arcturus. Roughly in the middle of that arc, you’ll find the Northern Crown constellation, which looks a bit like a smiley face. Sometime between now and September, if you look to the left-hand side of the Northern Crown, what will look like a new star will shine for five days or so.

This star system is called T. Coronae Borealis, also known as the Blaze Star, and most of the time, it is way too dim to be visible to the naked eye. But once roughly every 80 years, a violent thermonuclear explosion makes it over 10,000 times brighter. The last time it happened was in 1946, so now it’s our turn to see it.

Neighborhood litterbug

“The T. Coronae Borealis is a binary system. It is actually two stars,” said Gerard Van Belle, the director of science at Lowell Observatory in Flagstaff, Arizona. One of these stars is a white dwarf, an old star that has already been through its fusion-powered lifecycle. “It’s gone from being a main sequence star to being a giant star. And in the case of giant stars, what happens is their outer parts eventually get kind of pushed into outer space. What’s left behind is a leftover core of the star—that’s called a white dwarf,” Van Belle explained.

The white dwarf stage is normally a super peaceful retirement period for stars. The nuclear fusion reaction no longer takes place, which makes white dwarfs very dim. They are still pretty hot, though, and they’re super dense, with a mass comparable to our Sun squeezed into a volume resembling the Earth.

But the retirement of the white dwarf in T. Coronae Borealis is hardly peaceful, as it has a neighbor prone to littering. “Its companion star is in the red giant phase, where it is puffed up. Its outer parts are getting sloughed off and pushed into space. The material that is coming off the red giant is now falling onto the white dwarf,” Van Belle said.

Ticking time bomb

And it doesn’t take much littering to make the white dwarf explode. “The material from the red giant will accumulate on the white dwarf’s surface until it forms a layer that’s actually not that thick. Just a few meters—the depth of a deep swimming pool,” Van Belle explained. Most of the material coming off the red giant is hydrogen. And since the red dwarf is still hot, there will eventually be a spark that triggers a runaway nuclear fusion reaction. “That is what causes the explosion,” Van Belle said.

The explosion is a nova, which means it doesn’t kill either the white dwarf or the red giant as a supernova would. “Only about 5 percent of the hydrogen layer fuses into heavier elements like helium, and the rest just gets ejected into space. Then the process starts all over again because the explosion isn’t large enough to disrupt the red giant, the donor of all this hydrogen, so it just keeps doing its thing,” Van Belle told Ars. This is why we can predict this event with such precision.

Nova explosion visible to the naked eye expected any day now Read More »

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Blue Origin resumes human flights to suborbital space, but it wasn’t perfect

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“I lied” —

Blue Origin’s space capsule safely landed despite a problem with one of its parachutes.

–

Ed Dwight, 90, exits Blue Origin's crew capsule Sunday after a 10-minute flight to the edge of space.

Enlarge / Ed Dwight, 90, exits Blue Origin’s crew capsule Sunday after a 10-minute flight to the edge of space.

More than 60 years after he was denied an opportunity to become America’s first Black astronaut, Ed Dwight finally traveled into space Sunday with five other passengers on a 10-minute flight inside a Blue Origin capsule.

Dwight, a retired Air Force captain and test pilot, had a chance to become the first African American astronaut. He was one of 26 pilots the Air Force recommended to NASA for the third class of astronauts in 1963, but the agency didn’t select him. It took another 20 years for America’s first Black astronaut, Guion Bluford, to fly in space in 1983.

“Everything they did, I did, and I did it well,” Dwight said in a video released by Blue Origin. “If politics had changed, I would have gone to space in some kind of capacity.”

At the age of 90, Dwight finally entered the record books Sunday, becoming the oldest person to reach space, displacing the previous record-holder, actor William Shatner, who flew on a similar Blue Origin launch to the edge of space in 2021.

“I thought I didn’t need it in my life,” Dwight said after Sunday’s fight. “But I lied!”

Since retiring from the Air Force, Dwight became an accomplished sculptor. His works, which focus on Black history, are installed at memorials and monuments across the country.

“The transitions, the separations and stuff were a little bit more dynamic than I thought,” Dwight said in remarks after Sunday’s flight. “But that’s how it’s supposed to be. It makes your mind wonder, ‘Is something wrong?’ But no, it was absolutely terrific and the view … absolutely fantastic. This was a life-changing experience. Everybody needs to do this.”

Ed Dwight stands in front of an F-104 jet fighter in 1963.

Enlarge / Ed Dwight stands in front of an F-104 jet fighter in 1963.

Dwight and his five co-passengers lifted off from Blue Origin’s remote launch site in West Texas at 9: 35 am CDT (14: 35 UTC). Strapped into reclining seats inside a pressurized capsule, the passengers rode Blue Origin’s New Shepard rocket into the uppermost layers of the atmosphere. After burning its main engine more than two minutes, the rocket released the crew capsule and continued coasting upward to an apogee, or high point, of nearly 66 miles (107 kilometers), just above the internationally recognized boundary of space.

This was the seventh time Blue Origin, the space company owned by billionaire Jeff Bezos, has flown people to suborbital space, and the 25th flight overall of the company’s fleet of New Shepard rockets. It was the first time Blue Origin has launched people in nearly two years, resuming suborbital service after a rocket failure on an uncrewed research flight in September 2022. In December, Blue Origin launched another uncrewed suborbital research mission to set the stage for the resumption of human missions Sunday.

Joining Dwight on Blue Origin’s capsule were investor Mason Angel, French businessman Sylvain Chiron, software engineer Kenneth Hess, adventurer Carol Schaller, and Gopi Thotakura, an Indian pilot and entrepreneur. Dwight’s ticket with Blue Origin was sponsored by Space for Humanity, a nonprofit that seeks to expand access to space for all people, and the other five participants were paying passengers.

After cutoff of the New Shepard rocket engine, the passengers had a few minutes to unfasten their seatbelts and float around the cabin while taking in the view of Earth. They returned to their seats as the capsule descended back into the atmosphere. The reusable New Shepard booster reignited its main engine for a propulsive landing back in Texas, while the crew capsule deployed parachutes to slow for touchdown a few miles away.

Two of three

However, one of the three main parachutes did not fully unfurl as the capsule drifted back to the ground. The capsule is designed to safely land with two chutes, a capability Blue Origin demonstrated on a test flight in 2016.

“It looks like we do have two parachutes that have full inflation, the third is not quite fully inflated,” said Ariane Cornell, a Blue Origin official hosting the company’s live webcast Sunday. “Landing with two parachutes is perfectly OK for this system.”

Family members and Blue Origin personnel greeted the passengers as they exited the capsule. All six appeared to be in good spirits and good health.

Although it had no obvious ill effects on the crew or the spacecraft, Blue Origin engineers will investigate the malfunction to determine what went wrong. The capsule’s three main parachutes were supplied to Blue Origin by Airborne Systems, which manufactures parachutes for every US human-rated spacecraft.

One of the three main parachutes on Blue Origin's crew capsule did not fully inflate before landing.

Enlarge / One of the three main parachutes on Blue Origin’s crew capsule did not fully inflate before landing.

Blue Origin

Airborne also provides parachutes for SpaceX’s Dragon spacecraft, Boeing’s Starliner, and NASA’s Orion capsule. Those parachutes have different designs and sizes than the chutes used on Blue Origin’s capsule, but it wasn’t immediately clear if there might be any crossover concerns on other programs stemming from the malfunction on Sunday’s flight.

The Federal Aviation Administration, the regulatory agency that oversees US commercial space missions, said in a statement it did not consider the parachute issue a mishap. This statement suggests the incident will not trigger a mishap investigation that would require FAA oversight.

Before the 2022 launch failure, Blue Origin’s New Shepard program achieved a cadence, on average, of roughly one flight every two months. Virgin Galactic, the space tourism company founded by Richard Branson, ramped up the flight rate of its suborbital SpaceShipTwo spaceplane over the last year as Blue Origin’s rocket remained grounded.

But Virgin Galactic is about to halt operations of its own spaceship following one more flight with passengers next month. The company says it decided to suspend flights of the VSS Unity rocket plane to focus its resources on developing a fleet of larger air-launched spaceships that are easier to reuse.

This means Blue Origin, assuming it can regain or build on the cadence it demonstrated in 2021 and 2022, will be the only company serving the suborbital space tourism and research market for at least the next couple of years.

Blue Origin resumes human flights to suborbital space, but it wasn’t perfect Read More »

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The Atlantic hurricane season begins soon—hold on to your butts

hurricane forecast, Science / /

Batten down the hatches —

One reputable forecast team predicts 33 named storms.

–

Hurricane Dorian's satellite appearance on a Sunday morning in 2019.

Enlarge / Hurricane Dorian’s satellite appearance on a Sunday morning in 2019.

NOAA

Later this week, the US federal agency charged with weather forecasting will release its outlook for the 2024 Atlantic hurricane season at a news conference in Washington, DC. But we already know what the National Oceanic and Atmospheric Administration (NOAA) forecast will say: This year will likely be extremely active in the Atlantic Ocean, Gulf of Mexico, and Caribbean Sea.

The Atlantic season formally begins on June 1, and based on current trends, the first named storm may not develop until the middle of the month or later. But make no mistake—when the light switches on later this summer, the season is likely to be a blockbuster.

Why? Because the oceans are screaming at us.

In the Pacific Ocean, there is an increasingly high likelihood of a La Niña developing during the critical months of August, September, and October, when the Atlantic season peaks. This has a couple of effects in the Atlantic. First, through a combination of weaker trade winds and westerlies over the tropical Atlantic, La Niña tends to create a more placid atmosphere. This leads to less wind shear, which is favorable for the development and strengthening of tropical storms and hurricanes.

Secondly, there is a growing amount of data to support the idea that Atlantic storms tend to recurve into the open ocean less during La Niña years, with fewer systems becoming “fish storms” that do not interact with landmasses. Rather, a stronger high-pressure system such as the Bermuda High steers such storms westward into the Caribbean Sea or Gulf of Mexico—and potentially toward the United States.

Another signal from the oceans is the extremely warm temperatures in the tropical Atlantic right now. Due at least in part to climate change, the ocean is anomalously warm, with seas closer to August “normals” than what is to be expected in late May.

So, if you put together sizzling seas and low wind shear, you get a recipe for lots of hurricane activity.

Blockbuster forecasts

We’ve already seen this in seasonal forecasts from other outfits. The venerable forecast team at Colorado State University, led by Phil Klotzbach, has predicted an “extremely active” 2024 season with 23 named storms and 11 hurricanes. Each of these values is about 60 percent higher than a typical season.

One of the pre-season forecasts that most caught my attention came from the University of Pennsylvania, led by scientists Michael Mann, Shannon Christiansen, and Michael Kozar. They predict an astounding 33 named storms in the tropical Atlantic this year. This would eclipse the previous record of 30 named storms, set in 2020.

It might be easy to dismiss the Pennsylvania forecast. In some corners of the Internet, Mann is viewed as a master of climate doomerism for his outspoken views on the perils of a warming world. But if anything, since its first issuance in 2007, Mann’s forecast has proven to be conservative. In 2020, for example, the team predicted 20 named storms. So it’s a sobering outlook.

If you prefer a purely numerical prediction, the European Centre for Medium-Range Weather Forecasts—which produces the most reliable computational weather forecasts in the world—has been issuing seasonal hurricane outlooks for three decades.

European model seasonal forecast for Atlantic tropical activity over time.

Enlarge / European model seasonal forecast for Atlantic tropical activity over time.

ECMWF

As the center’s time series indicates, the seasonal forecast is far from perfect. (Most hurricane season forecasting, it must be said, is part art and part science.) But it is one of the best forecasts available, and for 2024, it made its highest prediction ever. The European model calls for an “accumulated cyclone energy” forecast twice as high as a normal year. This means that the duration and intensity of tropical activity are expected to double that of a typical season.

As always, a busy hurricane season does not guarantee that any part of the United States, Mexico, Central America, or the Caribbean Islands will get hit. Rather, it simply loads the dice, increasing the odds of a strike during a season. As a coastal resident, I don’t particularly like those odds.

The Atlantic hurricane season begins soon—hold on to your butts Read More »

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East Coast has a giant offshore freshwater aquifer—how did it get there?

aquifers, Earth science, fresh water, geology, glaciers, Science / /
Image of a large boat with a tall tower at its center, and a crane in the rear. It is floating on a dark blue ocean and set in front of a white cloud.

Enlarge / An oceangoing scientific drilling vessel may be needed to figure out how huge undersea aquifers formed.

One-quarter of the world’s population is currently water-stressed, using up almost their entire fresh water supply each year. The UN predicts that by 2030, this will climb to two-thirds of the population.

Freshwater is perhaps the world’s most essential resource, but climate change is enhancing its scarcity. An unexpected source may have the potential to provide some relief: offshore aquifers, giant undersea bodies of rock or sediment that hold and transport freshwater. But researchers don’t know how the water gets there, a question that needs to be resolved if we want to understand how to manage the water stored in them.

For decades, scientists have known about an aquifer off the US East Coast. It stretches from Martha’s Vineyard to New Jersey and holds almost as much water as two Lake Ontarios. Research presented at the American Geophysical Union conference in December attempted to explain where the water came from—a key step in finding out where other undersea aquifers lie hidden around the world.

As we discover and study more of them, offshore aquifers might become an unlikely resource for drinking water. Learning the water’s source can tell us if these freshwater reserves rebuild slowly over time or are a one-time-only emergency supply.

Reconstructing history

When ice sheets sat along the East Coast and the sea level was significantly lower than it is today, the coastline was around 100 kilometers further out to sea. Over time, freshwater filled small pockets in the open, sandy ground. Then, 10,000 years ago, the planet warmed, and sea levels rose, trapping the freshwater in the giant Continental Shelf Aquifer. But how that water came to be on the continental shelf in the first place is a mystery.

New Mexico Institute of Mining and Technology paleo-hydrogeologist Mark Person has been studying the aquifer since 1991. In the past three decades, he said, scientists’ understanding of the aquifer’s size, volume, and age has massively expanded. But they haven’t yet nailed down the water’s source, which could reveal where other submerged aquifers are hiding—if we learn the conditions that filled this one, we could look for other locations that had similar conditions.

“We can’t reenact Earth history,” Person said. Without the ability to conduct controlled experiments, scientists often resort to modeling to determine how geological structures formed millions of years ago. “It’s sort of like forensic workers looking at a crime scene,” he said.

Person developed three two-dimensional models of the offshore aquifer using seismic data and sediment and water samples from boreholes drilled onshore. Two models involved ice sheets melting; one did not.

Then, to corroborate the models, Person turned to isotopes—atoms with the same number of protons but different numbers of neutrons. Water mostly contains Oxygen-16, a lighter form of oxygen with two fewer neutrons than Oxygen-18.

Throughout the last million years, a cycle of planetary warming and cooling occurred every 100,000 years. During warming, the lighter 16O in the oceans evaporated into the atmosphere at a higher rate than the heavier 18O. During cooling, that lighter oxygen came down as snow, forming ice sheets with lower levels of 18O and leaving behind oceans with higher levels of 18O.

To determine if ice sheets played a role in forming the Continental Shelf Aquifer, Person explained, you have to look for water that is depleted in 18O—a sure sign that it came from ice sheets melting at their base. Person’s team used existing global isotope records from the shells of deep-ocean-dwelling animals near the aquifer. (The shells contain carbonate, an ion that includes oxygen pulled from the water).

Person then incorporated methods developed by a Columbia graduate student in 2019 that involve using electromagnetic imaging to finely map undersea aquifers. Since saltwater is more electrically conductive than freshwater, the boundaries between the two kinds of water are clear when electromagnetic pulses are sent through the seafloor: saltwater conducts the signal well, and freshwater doesn’t. What results looks sort of like a heat map, showing regions where fresh and saltwater are concentrated.

Person compared the electromagnetic and isotope data with his models to see which historical scenarios (ice or no ice) were statistically likely to form an aquifer that matched all the data. His results, which are in the review stage with the Geological Society of America Bulletin, suggest it’s very likely that ice sheets played a role in forming the aquifer.

“There’s a lot of uncertainty,” Person said, but “it’s the best thing we have going.”

East Coast has a giant offshore freshwater aquifer—how did it get there? Read More »

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We take a stab at decoding SpaceX’s ever-changing plans for Starship in Florida

artemis, cape canaveral, Commercial space, Features, Federal Aviation Administration, Kennedy Space Center, launch, launch complex 39a, NASA, Science, Space, spacex, starship / /
SpaceX's Starship tower (left) at Launch Complex 39A dwarfs the launch pad for the Falcon 9 rocket (right).

Enlarge / SpaceX’s Starship tower (left) at Launch Complex 39A dwarfs the launch pad for the Falcon 9 rocket (right).

There are a couple of ways to read the announcement from the Federal Aviation Administration that it’s kicking off a new environmental review of SpaceX’s plan to launch the most powerful rocket in the world from Florida.

The FAA said on May 10 that it plans to develop an Environmental Impact Statement (EIS) for SpaceX’s proposal to launch Starships from NASA’s Kennedy Space Center in Florida. The FAA ordered this review after SpaceX updated the regulatory agency on the projected Starship launch rate and the design of the ground infrastructure needed at Launch Complex 39A (LC-39A), the historic launch pad once used for Apollo and Space Shuttle missions.

Dual environmental reviews

At the same time, the US Space Force is overseeing a similar EIS for SpaceX’s proposal to take over a launch pad at Cape Canaveral Space Force Station, a few miles south of LC-39A. This launch pad, designated Space Launch Complex 37 (SLC-37), is available for use after United Launch Alliance’s last Delta rocket lifted off there in April.

On the one hand, these environmental reviews often take a while and could cloud Elon Musk’s goal of having Starship launch sites in Florida ready for service by the end of 2025. “A couple of years would not be a surprise,” said George Nield, an aerospace industry consultant and former head of the FAA’s Office of Commercial Space Transportation.

Another way to look at the recent FAA and Space Force announcements of pending environmental reviews is that SpaceX finally appears to be cementing its plans to launch Starship from Florida. These plans have changed quite a bit in the last five years.

The environmental reviews will culminate in a decision on whether to approve SpaceX’s proposals for Starship launches at LC-39A and SLC-37. The FAA will then go through a separate licensing process, similar to the framework used to license the first three Starship test launches from South Texas.

NASA has contracts with SpaceX worth more than $4 billion to develop a human-rated version of Starship to land astronauts on the Moon on the first two Artemis lunar landing flights later this decade. To do that, SpaceX must stage a fuel depot in low-Earth orbit to refuel the Starship lunar lander before it heads for the Moon. It will take a series of Starship tanker flights—perhaps 10 to 15—to fill the depot with cryogenic propellants.

Launching that many Starships over the course of a month or two will require SpaceX to alternate between at least two launch pads. NASA and SpaceX officials say the best way to do this is by launching Starships from one pad in Texas and another in Florida.

Earlier this week, Ars spoke with Lisa Watson-Morgan, who manages NASA’s human-rated lunar lander program. She was at Kennedy Space Center this week for briefings on the Starship lander and a competing lander from Blue Origin. One of the topics, she said, was the FAA’s new environmental review before Starship can launch from LC-39A.

“I would say we’re doing all we can to pull the schedule to where it needs to be, and we are working with SpaceX to make sure that their timeline, the EIS timeline, and NASA’s all work in parallel as much as we can to achieve our objectives,” she said. “When you’re writing it down on paper just as it is, it looks like there could be some tight areas, but I would say we’re collectively working through it.”

Officially, SpaceX plans to perform a dress rehearsal for the Starship lunar landing in late 2025. This will be a full demonstration, with refueling missions, an uncrewed landing of Starship on the lunar surface, then a takeoff from the Moon, before NASA commits to putting people on Starship on the Artemis III mission, currently slated for September 2026.

So you can see that schedules are already tight for the Starship lunar landing demonstration if SpaceX activates launch pads in Florida late next year.

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How the perils of space have affected asteroid Ryugu

asteroid, astronomy, magneticsm, planetary science, Ryugu, Science / /

Magnets: how do they stop working? —

Ryugu’s parent body appears to have had a fair amount of water present, too.

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Grey image of a complicated surface composed of many small rocks bound together by dust.

Enlarge / The surface of Ryugu. Image credit: JAXA, University of Tokyo, Kochi University, Rikkyo University, Nagoya University, Chiba Institute of Technology, Meiji University, Aizu University, AIST

An asteroid that has been wandering through space for billions of years is going to have been bombarded by everything from rocks to radiation. Billions of years traveling through interplanetary space increase the odds of colliding with something in the vast emptiness, and at least one of those impacts had enough force to leave the asteroid Ryugu forever changed.

When the Japanese Space Agency’s Hayabusa2 spacecraft touched down on Ryugu, it collected samples from the surface that revealed that particles of magnetite (which is usually magnetic) in the asteroid’s regolith are devoid of magnetism. A team of researchers from Hokkaido University and several other institutions in Japan are now offering an explanation for how this material lost most of its magnetic properties. Their analysis showed that it was caused by at least one high-velocity micrometeoroid collision that broke the magnetite’s chemical structure down so that it was no longer magnetic.

“We surmised that pseudo-magnetite was created [as] the result of space weathering by micrometeoroid impact,” the researchers, led by Hokkaido University professor Yuki Kimura, said in a study recently published in Nature Communications.

What remains…

Ryugu is a relatively small object with no atmosphere, which makes it more susceptible to space weathering—alteration by micrometeoroids and the solar wind. Understanding space weathering can actually help us understand the evolution of asteroids and the Solar System. The problem is that most of our information about asteroids comes from meteorites that fall to Earth, and the majority of those meteorites are chunks of rock from the inside of an asteroid, so they were not exposed to the brutal environment of interplanetary space. They can also be altered as they plummet through the atmosphere or by physical processes on the surface. The longer it takes to find a meteorite, the more information can potentially be lost.

Once part of a much larger body, Ryugu is a C-type, or carbonaceous, asteroid, meaning it is made of mostly clay and silicate rocks. These minerals normally need water to form, but their presence is explained by Ryugu’s history. It is thought that the asteroid itself was born from debris after its parent body was smashed to pieces in a collision. The parent body was also covered in water ice, which explains the magnetite, carbonates, and silicates found on Ryugu—these need water to form.

Magnetite is a ferromagnetic (iron-containing and magnetic) mineral. It is found in all C-type asteroids and can be used to determine their remanent, or remaining, magnetization. The remanent magnetization of an asteroid can reveal how intense the magnetic field was at the time and place of the magnetite’s formation.

Kimura and his team were able to measure remanent magnetization in two magnetite fragments (known as framboids because of their particular shape) from the Ryugu sample. It is proof of a magnetic field in the nebula our Solar System formed in, and shows the strength of that magnetic field at the time that the magnetite formed.

However, three other magnetite fragments analyzed were not magnetized at all. This is where space weathering comes in.

…and what was lost

Using electron holography, which is done with a transmission electron microscope that sends high-energy electron waves through a specimen, the researchers found that the three framboids in question did not have magnetic chemical structures. This made them drastically different from magnetite.

Further analysis with scanning transmission electron microscopy showed that the magnetite particles were mostly made of iron oxides, but there was less oxygen in those particles that had lost their magnetism, indicating that the material had experienced a chemical reduction, where electrons were donated to the system. This loss of oxygen (and oxidized iron) explained the loss of magnetism, which depends on the organization of the electrons in the magnetite. This is why Kimura refers to it as “pseudo-magnetite.”

But what triggered the reduction that demagnetized the magnetite in the first place? Kimura and his team found that there were more than a hundred metallic iron particles in the part of the specimen that the demagnetized framboids had come from. If a micrometeorite of a certain size had hit that region of Ryugu then it would have produced approximately that many particles of iron from the magnetite framboids. The researchers think this mystery object was rather small, or it would have had to have been moving incredibly fast.

“With increasing impact velocity, the estimated projectile size decreases,” they said in the same study.

Pseudo-magnetite might sound like an imposter, but it will actually help upcoming investigations that seek to find out more about what the early Solar System was like. Its presence indicates the former presence of water on an asteroid, as well as space weathering, such as micrometeoroid bombardment, that affected the asteroid’s composition. How much magnetism was lost also affects the overall remanence of the asteroid. Remanence is important in determining an object’s magnetism and the intensity of the magnetic field around it when it formed. What we know of the Solar System’s early magnetic field has been reconstructed from remanence records, many of which come from magnetite.

Some magnetic properties of those particles might have been lost eons ago, but so much more could be gained in the future from what remains.

Nature Communications, 2024.  DOI: 10.1038/s41467-024-47798-0

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The nature of consciousness, and how to enjoy it while you can

altered, consciousness, Neuroscience, psychedelics, psychology, Science / /

Remaining aware —

In his new book, Christof Koch views consciousness as a theorist and an aficionado.

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A black background with multicolored swirls filling the shape of a human brain.

Unraveling how consciousness arises out of particular configurations of organic matter is a quest that has absorbed scientists and philosophers for ages. Now, with AI systems behaving in strikingly conscious-looking ways, it is more important than ever to get a handle on who and what is capable of experiencing life on a conscious level. As Christof Koch writes in Then I Am Myself the World, “That you are intimately acquainted with the way life feels is a brute fact about the world that cries out for an explanation.” His explanation—bounded by the limits of current research and framed through Koch’s preferred theory of consciousness—is what he eloquently attempts to deliver.

Koch, a physicist, neuroscientist, and former president of the Allen Institute for Brain Science, has spent his career hunting for the seat of consciousness, scouring the brain for physical footprints of subjective experience. It turns out that the posterior hot zone, a region in the back of the neocortex, is intricately connected to self-awareness and experiences of sound, sight, and touch. Dense networks of neocortical neurons in this area connect in a looped configuration; output signals feedback into input neurons, allowing the posterior hot zone to influence its own behavior. And herein, Koch claims, lies the key to consciousness.

In the hot zone

According to integrated information theory (IIT)—which Koch strongly favors over a multitude of contending theories of consciousness—the Rosetta Stone of subjective experience is the ability of a system to influence itself: to use its past state to affect its present state and its present state to influence its future state.

Billions of neurons exist in the cerebellum, but they are wired “with nonoverlapping inputs and outputs … in a feed-forward manner,” writes Koch. He argues that a structure designed in this way, with limited influence over its own future, is not likely to produce consciousness. Similarly, the prefrontal cortex might allow us to perform complex calculations and exhibit advanced reasoning skills, but such traits do not equate to a capacity to experience life. It is the “reverberatory, self-sustaining excitatory loops prevalent in the neocortex,” Koch tells us, that set the stage for subjective experience to arise.

This declaration matches the experimental evidence Koch presents in Chapter 6: Injuries to the cerebellum do not eliminate a person’s awareness of themselves in relation to the outside world. Consciousness remains, even in a person who can no longer move their body with ease. Yet injuries to the posterior hot zone within the neocortex significantly change a person’s perception of auditory, visual, and tactile information, altering what they subjectively experience and how they describe these experiences to themselves and others.

Does this mean that artificial computer systems, wired appropriately, can be conscious? Not necessarily, Koch says. This might one day be possible with the advent of new technology, but we are not there yet. He writes. “The high connectivity [in a human brain] is very different from that found in the central processing unit of any digital computer, where one transistor typically connects to a handful of other transistors.” For the foreseeable future, AI systems will remain unconscious despite appearances to the contrary.

Koch’s eloquent overview of IIT and the melodic ease of his neuroscientific explanations are undeniably compelling, even for die-hard physicalists who flinch at terms like “self-influence.” His impeccably written descriptions are peppered with references to philosophers, writers, musicians, and psychologists—Albert Camus, Viktor Frankl, Richard Wagner, and Lewis Carroll all make appearances, adding richness and relatability to the narrative. For example, as an introduction to phenomenology—the way an experience feels or appears—he aptly quotes Eminem: “I can’t tell you what it really is, I can only tell you what it feels like.”

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“Outrageously” priced weight-loss drugs could bankrupt US health care

bernie sanders, GLP-1, health, health care costs, medicaid, medicare, premiums, Science, wegovy, weight loss / /

Collision course —

Prices would need to be dramatically slashed to avoid increasing the national deficit.

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Packaging for Wegovy, manufactured by Novo Nordisk, is seen in this illustration photo.

Enlarge / Packaging for Wegovy, manufactured by Novo Nordisk, is seen in this illustration photo.

With the debut of remarkably effective weight-loss drugs, America’s high obesity rate and its uniquely astronomical prescription drug pricing appear to be set on a catastrophic collision course—one that threatens to “bankrupt our entire health care system,” according to a new Senate report that modeled the economic impact of the drugs in different uptake scenarios.

If just half of the adults in the US with obesity start taking a new weight-loss drug, such as Wegovy, the collective cost would total an estimated $411 billion per year, the analysis found. That’s more than the $406 billion Americans spent in 2022 on all prescription drugs combined.

While the bulk of the spending on weight-loss drugs will occur in the commercial market—which could easily lead to spikes in health insurance premiums—taxpayer-funded Medicare and Medicaid programs will also see an extraordinary financial burden. In the scenario that half of adults with obesity go on the drug, the cost to those federal programs would total $166 billion per year, rivaling the programs’ total 2022 drug costs of $175 billion.

In all, by 2031, total US spending on prescription drugs is poised to reach over $1 trillion per year due to weight-loss drugs. Without them, the baseline projected spending on all prescription drugs would be just under $600 billion.

The analysis was put together by the Senate’s Health, Education, Labor, and Pensions (HELP) committee, chaired by staunch drug-pricing critic Bernie Sanders (I-Vt). And it’s quick to knock down a common argument about the high prices for smash-hit weight-loss drugs. That is, with their high effectiveness, the drugs will improve people’s health in wide-ranging ways, including controlling diabetes, improving cardiovascular health, and potentially more. And, with those improvements, people won’t need as much health care, generally, lowering health care costs across the board.

But, while the drugs do appear to have wide-ranging, life-altering benefits for overall health, the prices of the drugs are still set too high to be entirely offset by any savings in health care use. The HELP committee analysis cited a March Congressional Budget Office (CBO) report that found: “at their current prices, [anti-obesity medicines] would cost the federal government more than it would save from reducing other health care spending—which would lead to an overall increase in the deficit over the next 10 years.” Moreover, in April, the head of the CBO said that the drugmakers would have to slash prices of their weight-loss drugs by 90 percent to “get in the ballpark” of not increasing the national deficit.

The HELP committee report offered a relatively simple solution to the problem: Drugmakers should set their US prices to match the relatively low prices they’ve set in other countries. The report focused on Wegovy because it currently accounts for the most US prescriptions in the new class of weight-loss drugs (GLP-1 drugs). Wegovy is made by Denmark-based Novo Nordisk.

In the US, the estimated net price (after rebates) of Wegovy is $809 per month. In Denmark, the price is $186 per month. A study by researchers at Yale estimated that drugs like Wegovy can be profitably manufactured for less than $5 per month.

If Novo Nordisk set its US prices for Wegovy to match the Danish price, spending to treat half of US adults with obesity would drop from $411 billion to $94.5 billion, a roughly $316.5 billion savings.

Without a dramatic price cut, Americans will likely face either losing access to the drugs or shouldering higher overall health care costs, or some of both. The HELP committee report highlighted how this recently played out in North Carolina. In January, the board of trustees for the state employee health plan voted to end all coverage of Wegovy and other GLP-1 drugs due to the cost. Estimates found that if the plan continued to cover the drugs, the state would need to nearly double health insurance premiums to offset the costs.

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Cats playing with robots proves a winning combo in novel art installation

animal behavior, animals, cat behavior, Cats, robotics, Science, science and art / /

The feline factor —

Cat Royale project explores what it takes to trust a robot to look after beloved pets.

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Cat with the robot arm in the Cat Royale installation

Enlarge / A kitty named Clover prepares to play with a robot arm in the Cat Royale “multi-species” science/art installation .

Blast Theory – Stephen Daly

Cats and robots are a winning combination, as evidenced by all those videos of kitties riding on Roombas. And now we have Cat Royale, a “multispecies” live installation in which three cats regularly “played” with a robot over 12 days, carefully monitored by human operators. Created by computer scientists from the University of Nottingham in collaboration with artists from a group called Blast Theory, the installation debuted at the World Science Festival in Brisbane, Australia, last year and is now a touring exhibit. The accompanying YouTube video series recently won a Webby Award, and a paper outlining the insights gleaned from the experience was similarly voted best paper at the recent Computer-Human Conference (CHI’24).

“At first glance, the project is about designing a robot to enrich the lives of a family of cats by playing with them,” said co-author Steve Benford of the University of Nottingham, who led the research, “Under the surface, however, it explores the question of what it takes to trust a robot to look after our loved ones and potentially ourselves.” While cats might love Roombas, not all animal encounters with robots are positive: Guide dogs for the visually impaired can get confused by delivery robots, for example, while the rise of lawn mowing robots can have a negative impact on hedgehogs, per Benford et al.

Blast Theory and the scientists first held a series of exploratory workshops to ensure the installation and robotic design would take into account the welfare of the cats. “Creating a multispecies system—where cats, robots, and humans are all accounted for—takes more than just designing the robot,” said co-author Eike Schneiders of Nottingham’s Mixed Reality Lab about the primary takeaway from the project. “We had to ensure animal well-being at all times, while simultaneously ensuring that the interactive installation engaged the (human) audiences around the world. This involved consideration of many elements, including the design of the enclosure, the robot, and its underlying systems, the various roles of the humans-in-the-loop, and, of course, the selection of the cats.”

Based on those discussions, the team set about building the installation: a bespoke enclosure that would be inhabited by three cats for six hours a day over 12 days. The lucky cats were named Ghostbuster, Clover, and Pumpkin—a parent and two offspring to ensure the cats were familiar with each other and comfortable sharing the enclosure. The enclosure was tricked out to essentially be a “utopia for cats,” per the authors, with perches, walkways, dens, a scratching post, a water fountain, several feeding stations, a ball run, and litter boxes tucked away in secluded corners.

(l-r) Clover, Pumpkin, and Ghostbuster spent six hours a day for 12 days in the installation.

Enlarge / (l-r) Clover, Pumpkin, and Ghostbuster spent six hours a day for 12 days in the installation.

E. Schneiders et al., 2024

As for the robot, the team chose the Kino Gen3 lite robot arm, and the associated software was trained on over 7,000 videos of cats. A decision engine gave the robot autonomy and proposed activities for specific cats. Then a human operator used an interface control system to instruct the robot to execute the movements. The robotic arm’s two-finger gripper was augmented with custom 3D-printed attachments so that the robot could manipulate various cat toys and accessories.

Each cat/robot interaction was evaluated for a “happiness score” based on the cat’s level of engagement, body language, and so forth. Eight cameras monitored the cat and robot activities, and that footage was subsequently remixed and edited into daily YouTube highlight videos and, eventually, an eight-hour film.

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Using vague language about scientific facts misleads readers

beliefs, facts, Human behavior, Science, Science communication / /
Using vague language about scientific facts misleads readers

Anyone can do a simple experiment. Navigate to a search engine that offers suggested completions for what you type, and start typing “scientists believe.” When I did it, I got suggestions about the origin of whales, the evolution of animals, the root cause of narcolepsy, and more. The search results contained a long list of topics, like “How scientists believe the loss of Arctic sea ice will impact US weather patterns” or “Scientists believe Moon is 40 million years older than first thought.”

What do these all have in common? They’re misleading, at least in terms of how most people understand the word “believe.” In all these examples, scientists have become convinced via compelling evidence; these are more than just hunches or emotional compulsions. Given that difference, using “believe” isn’t really an accurate description. Yet all these examples come from searching Google News, and so are likely to come from journalistic outlets that care about accuracy.

Does the difference matter? A recent study suggests that it does. People who were shown headlines that used subjective verbs like “believe” tended to view the issue being described as a matter of opinion—even if that issue was solidly grounded in fact.

Fact vs. opinion

The new work was done by three researchers at Stanford University: Aaron Chueya, Yiwei Luob, and Ellen Markman. “Media consumption is central to how we form, maintain, and spread beliefs in the modern world,” they write. “Moreover, how content is presented may be as important as the content itself.” The presentation they’re interested in involves what they term “epistemic verbs,” or those that convey information about our certainty regarding information. To put that in concrete terms, “’Know’ presents [a statement] as a fact by presup­posing that it is true, ‘believe’ does not,” they argue.

So, while it’s accurate to say, “Scientists know the Earth is warming, and that warming is driven by human activity,” replacing “know” with “believe” presents an inaccurate picture of the state of our knowledge. Yet, as noted above, “scientists believe” is heavily used in the popular press. Chueya, Luob, and Markman decided to see whether this makes a difference.

They were interested in two related questions. One is whether the use of verbs like believe and think influences how readers view whether the concepts they’re associated with are subjective issues rather than objective, factual ones. The second is whether using that phrasing undercuts the readers’ willingness to accept something as a fact.

To answer those questions, the researchers used a subject-recruiting service called Prolific to recruit over 2,700 participants who took part in a number of individual experiments focused on these issues. In each experiment, participants were given a series of headlines and asked about what inferences they drew about the information presented in them.

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