Science

In a rare disclosure, the Pentagon provides an update on the X-37B spaceplane

Boeing, military space, Science, Space, space force, spaceplane, Uncategorized, X-37b / Kris Guyer / October 10, 2024

“When it’s close to the Earth, it’s close enough to the atmosphere to turn where it is,” she said. “Which means our adversaries don’t know—and that happens on the far side of the Earth from our adversaries—where it’s going to come up next. And we know that that drives them nuts. And I’m really glad about that.”

Breaking the silence

The Pentagon rarely releases an update on the X-37B spaceplane in the middle of a mission. During previous flights, military officials typically provided some basic information about the mission before its launch, then went silent until the X-37B returned for landing. The military keeps specifics about the spaceplane’s activities in orbit a secret.

This made the Space Force’s announcement Thursday somewhat of a surprise. When the seventh flight of the X-37B launched, there were indications that the spacecraft would soar into a much higher orbit than it did on any of its six prior missions.

In February, a sleuthing satellite tracking hobbyist spotted the X-37B in orbit by observing sunlight reflected off of the spacecraft as it flew thousands of miles above Earth. Follow-up detections confirmed the discovery, allowing amateur observers to estimate that the X-37B was flying in a highly elliptical orbit ranging between roughly 300 and 38,600 miles in altitude (186-by-23,985 miles). The orbit was inclined 59.1 degrees to the equator.

On its previous missions, the X-37B was confined to low-Earth orbit a few hundred miles above the planet. When it became apparent that the latest mission was cruising at a significantly higher altitude, analysts and space enthusiasts speculated on what the secret spaceplane was doing and how it would come back to Earth. A direct reentry into the atmosphere from the spaceplane’s elliptical orbit would expose the craft’s heat shield to hotter temperatures than any of its previous returns.

Now, we have an answer to the latter question.

As for what it’s doing up there, the Space Force said the spaceplane on this mission has “conducted radiation effect experiments and has been testing space domain awareness technologies in a highly elliptical orbit.” The orbit brings the X-37B through the Van Allen radiation belts and crosses several orbital regimes populated by US and foreign communications, navigation, and surveillance satellites.

Military officials have said previous X-37B flights have tested a Hall-effect ion thruster and tested other experimental space technologies without elaborating on their details. X-37Bs have also secretly deployed small military satellites in orbit.

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Rapid analysis finds climate change’s fingerprint on Hurricane Helene

atmospheric science, climate change, Earth science, hurricane helene, hurricanes, meteorology, Rainfall, Science / Rejus Almole / October 9, 2024

The researchers identified two distinct events associated with Helene’s landfall. The first was its actual landfall along the Florida coast. The second was the intense rainfall on the North Carolina/Tennessee border. This rainfall came against a backdrop of previous heavy rain caused by a stalled cold front meeting moisture brought north by the fringes of the hurricane. These two regions were examined separately.

A changed climate

In these two regions, the influence of climate change is estimated to have caused a 10 percent increase in the intensity of the rainfall. That may not seem like much, but it adds up. Over both a two- and three-day window centered on the point of maximal rainfall, climate change is estimated to have increased rainfall along the Florida Coast by 40 percent. For the southern Appalachians, the boost in rainfall is estimated to have been 70 percent.

The probability of storms with the wind intensity of Helene hitting land near where it did is about a once-in-130-year event in the IRIS dataset. Climate change has altered that so it’s now expected to return about once every 50 years. The high sea surface temperatures that helped fuel Helene are estimated to have been made as much as 500 times more likely by our changed climate.

Overall, the researchers estimate that rain events like Helene’s landfall should now be expected about once every seven years, although the uncertainty is large (running from three to 25 years). For the Appalachian region, where rainfall events this severe don’t appear in our records, they are likely to now be a once-in-every-70-years event thanks to climate warming (with an uncertainty of between 20 and 3,000 years).

“Together, these findings show that climate change is enhancing conditions conducive to the most powerful hurricanes like Helene, with more intense rainfall totals and wind speeds,” the researchers behind the work conclude.

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Drug makers can’t make knockoff weight-loss drugs anymore—and they’re mad

compounding pharmacy, fda, GLP-1, health, lilly, outsourcing facility, Science, semaglutide, Tirzepatide, weight loss / Paul Patrick / October 9, 2024

Compounding pharmacies are suing the Food and Drug Administration so they can keep making imitation versions of popular—and lucrative—tirzepatide drugs, namely knockoffs of Mounjaro for diabetes and Zepbound for weight loss.

Generally, compounding pharmacies make customized formulations of drugs for patients with specific needs, like when a patient has an allergy to a filler ingredient or if a child needs a liquid version of a drug that normally comes as a capsule. But larger compounding operations are also legally allowed to make imitations of branded drugs if those drugs are in short supply, acting as a stopgap for patients.

Tirzepatide has certainly been in short supply in recent years. Given the high prevalence of diabetes and obesity in America and the drug’s effectiveness, demand for tirzepatide and other drugs in the new GLP-1 class have skyrocketed, and many patients have struggled to fill prescriptions. The FDA placed tirzepatide on its drug shortage list in December of 2022—and that’s where it remained until last week.

On October 2, the FDA announced that the tirzepatide shortage had been resolved and that the nation’s supply of GLP-1 drugs was stabilizing, though other drugs in the class, including semaglutide, remain in short supply.

“FDA confirmed with the drug’s manufacturer [Eli Lilly] that their stated product availability and manufacturing capacity can meet the present and projected national demand,” the agency said in its announcement. However, it cautioned that patients and prescribers “may still see intermittent localized supply disruptions” as the drugs move through the supply chain.

End of an era

With the resolution, compounding pharmacies are no longer able to produce tirzepatide. And the FDA highlighted the point to the drug makers, writing in bold that the agency “reminds compounders of the legal restrictions on making copies of FDA-approved drugs.”

Drug makers can’t make knockoff weight-loss drugs anymore—and they’re mad Read More »

Octopus suckers inspire new tech for gripping objects underwater

adhesives, Biology, biomimicry, cephalopods, materials science, octopuses, Science / Rejus Almole / October 9, 2024

Over the last few years, Virginia Tech scientists have been looking to the octopus for inspiration to design technologies that can better grip a wide variety of objects in underwater environments. Their latest breakthrough is a special switchable adhesive modeled after the shape of the animal’s suckers, according to a new paper published in the journal Advanced Science.

“I am fascinated with how an octopus in one moment can hold something strongly, then release it instantly. It does this underwater, on objects that are rough, curved, and irregular—that is quite a feat,” said co-author and research group leader Michael Bartlett. “We’re now closer than ever to replicating the incredible ability of an octopus to grip and manipulate objects with precision, opening up new possibilities for exploration and manipulation of wet or underwater environments.”

As previously reported, there are several examples in nature of efficient ways to latch onto objects in underwater environments, per the authors. Mussels, for instance, secrete adhesive proteins to attach themselves to wet surfaces, while frogs have uniquely structured toe pads that create capillary and hydrodynamic forces for adhesion. But cephalopods like the octopus have an added advantage: The adhesion supplied by their grippers can be quickly and easily reversed, so the creatures can adapt to changing conditions, attaching to wet and dry surfaces.

From a mechanical engineering standpoint, the octopus has an active, pressure-driven system for adhesion. The sucker’s wide outer rim creates a seal with the object via a pressure differential between the chamber and the surrounding medium. Then muscles (serving as actuators) contract and relax the cupped area behind the rim to add or release pressure as needed.

There have been several attempts to mimic cephalopods when designing soft robotic grippers, for example. Back in 2022, Bartlett and his colleagues wanted to go one step further and recreate not just the switchable adhesion but also the integrated sensing and control. The result was Octa-Glove, a wearable system for gripping underwater objects that mimicked the arm of an octopus.

Improving the Octa-Glove

Grabbing and releasing underwater objects of different sizes and shapes with an octopus-inspired adhesive. Credit: Chanhong Lee and Michael Bartlett

For the adhesion, they designed silicone stalks capped with a pneumatically controlled membrane, mimicking the structure of octopus suckers. These adhesive elements were then integrated with an array of LIDAR optical proximity sensors and a micro-control for the real-time detection of objects. When the sensors detect an object, the adhesion turns on, mimicking the octopus’s nervous and muscular systems. The team used a neoprene wetsuit glove as a base for the wearable glove, incorporating the adhesive elements and sensors in each finger, with flexible pneumatic tubes inserted at the base of the adhesive elements.

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Google identifies low noise “phase transition” in its quantum processor

Computer science, error rate, Google, NISQ, quantum computing, quantum mechanics, Science / Tim Belzer / October 9, 2024

Noisy, but not that noisy

Benchmark may help us understand how quantum computers can operate with low error.

Image of a chip above iridescent wiring.

Google’s Sycamore processor. Credit: Google

Back in 2019, Google made waves by claiming it had achieved what has been called “quantum supremacy”—the ability of a quantum computer to perform operations that would take a wildly impractical amount of time to simulate on standard computing hardware. That claim proved to be controversial, in that the operations were little more than a benchmark that involved getting the quantum computer to behave like a quantum computer; separately, improved ideas about how to perform the simulation on a supercomputer cut the time required down significantly.

But Google is back with a new exploration of the benchmark, described in a paper published in Nature on Wednesday. It uses the benchmark to identify what it calls a phase transition in the performance of its quantum processor and uses it to identify conditions where the processor can operate with low noise. Taking advantage of that, they again show that, even giving classical hardware every potential advantage, it would take a supercomputer a dozen years to simulate things.

Cross entropy benchmarking

The benchmark in question involves the performance of what are called quantum random circuits, which involves performing a set of operations on qubits and letting the state of the system evolve over time, so that the output depends heavily on the stochastic nature of measurement outcomes in quantum mechanics. Each qubit will have a probability of producing one of two results, but unless that probability is one, there’s no way of knowing which of the results you’ll actually get. As a result, the output of the operations will be a string of truly random bits.

If enough qubits are involved in the operations, then it becomes increasingly difficult to simulate the performance of a quantum random circuit on classical hardware. That difficulty is what Google originally used to claim quantum supremacy.

The big challenge with running quantum random circuits on today’s hardware is the inevitability of errors. And there’s a specific approach, called cross-entropy benchmarking, that relates the performance of quantum random circuits to the overall fidelity of the hardware (meaning its ability to perform error-free operations).

Google Principal Scientist Sergio Boixo likened performing quantum random circuits to a race between trying to build the circuit and errors that would destroy it. “In essence, this is a competition between quantum correlations spreading because you’re entangling, and random circuits entangle as fast as possible,” he told Ars. “We use two qubit gates that entangle as fast as possible. So it’s a competition between correlations or entanglement growing as fast as you want. On the other hand, noise is doing the opposite. Noise is killing correlations, it’s killing the growth of correlations. So these are the two tendencies.”

The focus of the paper is using the cross-entropy benchmark to explore the errors that occur on the company’s latest generation of Sycamore chip and use that to identify the transition point between situations where errors dominate, and what the paper terms a “low noise regime,” where the probability of errors are minimized—where entanglement wins the race. The researchers likened this to a phase transition between two states.

Low noise performance

The researchers used a number of methods to identify the location of this phase transition, including numerical estimates of the system’s behavior and experiments using the Sycamore processor. Boixo explained that the transition point is related to the errors per cycle, with each cycle involving performing an operation on all of the qubits involved. So, the total number of qubits being used influences the location of the transition, since more qubits means more operations to perform. But so does the overall error rate on the processor.

If you want to operate in the low noise regime, then you have to limit the number of qubits involved (which has the side effect of making things easier to simulate on classical hardware). The only way to add more qubits is to lower the error rate. While the Sycamore processor itself had a well-understood minimal error rate, Google could artificially increase that error rate and then gradually lower it to explore Sycamore’s behavior at the transition point.

The low noise regime wasn’t error free; each operation still has the potential for error, and qubits will sometimes lose their state even when sitting around doing nothing. But this error rate could be estimated using the cross-entropy benchmark to explore the system’s overall fidelity. That wasn’t the case beyond the transition point, where errors occurred quickly enough that they would interrupt the entanglement process.

When this occurs, the result is often two separate, smaller entangled systems, each of which were subject to the Sycamore chip’s base error rates. The researchers simulated this by creating two distinct clusters of entangled qubits that could be entangled with each other by a single operation, allowing them to turn entanglement on and off at will. They showed that this behavior allowed a classical computer to spoof the overall behavior by breaking the computation up into two manageable chunks.

Ultimately, they used their characterization of the phase transition to identify the maximum number of qubits they could keep in the low noise regime given the Sycamore processor’s base error rate and then performed a million random circuits on them. While this is relatively easy to do on quantum hardware, even assuming that we could build a supercomputer without bandwidth constraints, simulating it would take roughly 10,000 years on an existing supercomputer (the Frontier system). Allowing all of the system’s storage to operate as secondary memory cut the estimate down to 12 years.

What does this tell us?

Boixo emphasized that the value of the work isn’t really based on the value of performing random quantum circuits. Truly random bit strings might be useful in some contexts, but he emphasized that the real benefit here is a better understanding of the noise level that can be tolerated in quantum algorithms more generally. Since this benchmark is designed to make it as easy as possible to outperform classical computations, you would need the best standard computers here to have any hope of beating them to the answer for more complicated problems.

“Before you can do any other application, you need to win on this benchmark,” Boixo said. “If you are not winning on this benchmark, then you’re not winning on any other benchmark. This is the easiest thing for a noisy quantum computer compared to a supercomputer.”

Knowing how to identify this phase transition, he suggested, will also be helpful for anyone trying to run useful computations on today’s processors. “As we define the phase, it opens the possibility for finding applications in that phase on noisy quantum computers, where they will outperform classical computers,” Boixo said.

Implicit in this argument is an indication of why Google has focused on iterating on a single processor design even as many of its competitors have been pushing to increase qubit counts rapidly. If this benchmark indicates that you can’t get all of Sycamore’s qubits involved in the simplest low-noise regime calculation, then it’s not clear whether there’s a lot of value in increasing the qubit count. And the only way to change that is to lower the base error rate of the processor, so that’s where the company’s focus has been.

All of that, however, assumes that you hope to run useful calculations on today’s noisy hardware qubits. The alternative is to use error-corrected logical qubits, which will require major increases in qubit count. But Google has been seeing similar limitations due to Sycamore’s base error rate in tests that used it to host an error-corrected logical qubit, something we hope to return to in future coverage.

Nature, 2024. DOI: 10.1038/s41586-024-07998-6 (About DOIs).

John is Ars Technica’s science editor. He has a Bachelor of Arts in Biochemistry from Columbia University, and a Ph.D. in Molecular and Cell Biology from the University of California, Berkeley. When physically separated from his keyboard, he tends to seek out a bicycle, or a scenic location for communing with his hiking boots.

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Your doctor’s office could be reading your blood pressure all wrong

blood pressure, health, hypertension, JAMA, Science / Rejus Almole / October 8, 2024

Under pressure

Before participants took readings in any of the positions, the researchers had them simulate walking into a doctor’s appointment. They walked for two minutes and then sat calmly in position for five minutes before taking the three readings. Before moving onto the next position, they got up and walked again and sat for another five minutes. The participants were also randomized into groups that took the first three readings (desk 1, lap, side) in different orders, with all groups ending on desk 2.

The researchers then compared the differences between desk 1 and desk 2 to differences between lap and desk 1 and side and desk 1 for each participant. The desk 1-desk 2 differences captured intrinsic variability of blood pressure reading within each participant. The comparisons to lap-desk 1 and side-desk 1 captured changes based on the improper arm positions.

In all, there was little difference in the desk 1-desk 2 comparison, with participants having a mean difference of -0.21 mm Hg in systolic blood pressure and 0.09 in diastolic. But, the improper arm positions had significant effects on the readings. Lap arm position resulted in a mean increase of 4 mm Hg in both systolic and diastolic readings. Side arm position led to systolic readings that were 6.5 mm Hg higher and diastolic readings that were 4 mm Hg higher. For those with high blood pressure readings—about 36 percent of the participants—the wrong arm position caused yet higher readings, with systolic readings about 9 mm Hg higher than desk readings.

The authors speculate that simple physiological mechanisms likely explain the increase in blood pressure when the arm is lower than the heart—more gravitational pull, compensatory constriction of blood vessels, and muscle contraction may lead to higher pressure. As for why health care providers are known to sometimes use these wrong arm positions, it may be a lack of awareness, training, equipment, and/or resources.

The authors of the study call for more training and education about proper blood pressure measurements, which are essential for appropriate management of hypertension and prevention of cardiovascular disease.

Your doctor’s office could be reading your blood pressure all wrong Read More »

SpaceX’s next Starship launch—and first catch—could happen this weekend

Commercial space, Federal Aviation Administration, launch, Science, Space, spacex, Starbase, starship / Rejus Almole / October 8, 2024

The FAA is still reviewing plans for the fifth Starship test flight, but could approve it soon.

SpaceX’s fully-stacked Super Heavy booster and Starship upper stage at the company’s launch site in South Texas. Credit: SpaceX

We may not have to wait as long as we thought for the next test flight of SpaceX’s Starship rocket.

The world’s most powerful launcher could fly again as soon as Sunday, SpaceX says, assuming the Federal Aviation Administration grants approval. The last public statement released from the FAA suggested the agency didn’t expect to determine whether to approve a commercial launch license for SpaceX’s next Starship test flight before late November.

There’s some optimism at SpaceX that the FAA might issue a launch license much sooner, perhaps in time for Starship to fly this weekend. The launch window Sunday opens at 7 am CDT (8 am EDT; 12: 00 UTC), about a half-hour before sunrise at SpaceX’s Starbase launch site in South Texas.

“The fifth flight test of Starship will aim to take another step towards full and rapid reusability,” SpaceX wrote in an update posted on its website. “The primary objectives will be attempting the first ever return to launch site and catch of the Super Heavy booster and another Starship reentry and landing burn, aiming for an on-target splashdown of Starship in the Indian Ocean.”

Stacked together, the Super Heavy booster, or first stage, and the Starship upper stage stand nearly 400 feet (121 meters) tall. The Super Heavy booster—itself bigger than the fuselage of a 747 jumbo jet—will vertically return to the Starbase launch pad guided by cold gas thrusters, aerodynamic grid fins, and propulsive maneuvers with its methane-fueled Raptor engines.

Once the booster’s Raptor engines slow it to a hover, mechanical arms on the launch pad tower will close in around the rocket and capture it in midair. If you’re into rockets, or just want to spice up your morning, you don’t want to miss this. We’ll have a more detailed story before the launch previewing the timeline of events.

Safety measures

The FAA has been reviewing SpaceX’s plans to bring the Super Heavy booster back to the Starbase launch pad for months.

Most recently, the agency’s review of SpaceX’s proposed flight plan has focused on the effects of the rocket’s sonic boom as it comes back to Earth. The FAA and other agencies are also studying how a disposable section of the booster, called a hot-staging ring, might impact the environment when it falls into the sea just offshore from Starbase, located on the Gulf Coast east of Brownsville.

During SpaceX’s most recent Starship test flight in June, the Super Heavy booster completed a control descent to a predetermined location in the Gulf of Mexico, giving engineers enough confidence to try a return to the launch site on the next mission.

SpaceX protested the length of time the FAA said it needed to review the flight plan, after the federal regulator previously told SpaceX it expected to make a license determination in September.

“Unfortunately, instead of focusing resources on critical safety analysis and collaborating on rational safeguards to protect both the public and the environment, the licensing process has been repeatedly derailed by issues ranging from the frivolous to the patently absurd,” SpaceX wrote in a statement last month.

“I think the two-month delay is necessary to comply with the launch requirements, and I think that’s an important part of safety culture,” said Michael Whitaker, the FAA administrator, in a congressional hearing September 24.

The FAA is responsible for ensuring commercial space launches do not endanger the public and comport with the US government’s national security and foreign policy interests. Earlier this year, SpaceX was also fined by the Texas Commission on Environmental Quality and the Environmental Protection Agency for alleged violations of environmental regulations related to the launch pad’s water system, which cools a steel flame deflector under the 33 main engines of Starship’s Super Heavy booster.

Ars contacted an FAA spokesperson Tuesday about the status of the agency’s review of the Starship launch license request, but did not receive a response.

Artist’s illustration of SpaceX’s Super Heavy booster coming in for a catch by the launch pad’s mechanical arms. Credit: SpaceX

Teams at Starbase completed two partial propellant loading tests on the fully stacked Starship rocket in recent days. Early Tuesday, SpaceX tested the water deluge system at the launch pad two times, presumably to check the system’s ability to activate minutes apart to protect the pad during launch and recovery of the Super Heavy booster.

Later Tuesday, SpaceX removed the Starship upper stage from the Super Heavy booster. This is required for technicians to perform one of the final tasks to prepare for launch—installing the rocket’s flight termination system, which would destroy the rocket if it veers off course.

“We accept no compromises when it comes to ensuring the safety of the public and our team, and the return will only be attempted if conditions are right,” SpaceX said.

SpaceX outlined additional human-in-the-loop safety criteria for the upcoming Starship flight. SpaceX launches are typically fully automated from liftoff through the end of the mission.

“Thousands of distinct vehicle and pad criteria must be met prior to a return and catch attempt of the Super Heavy booster, which will require healthy systems on the booster and tower and a manual command from the mission’s flight director,” SpaceX wrote. “If this command is not sent prior to the completion of the boostback burn, or if automated health checks show unacceptable conditions with Super Heavy or the tower, the booster will default to a trajectory that takes it to a landing burn and soft splashdown in the Gulf of Mexico.”

Recovering the Super Heavy booster back at the launch pad is critical for SpaceX’s ambition to rapidly reuse the rocket. Eventually, SpaceX will also recover and reuse the Starship portion of the rocket, but for now, the company is sticking to water landings for the ship.

Extensive upgrades

SpaceX teams in Texas have beefed up the launch tower and catch arms in the last few months, working around the clock to add structural stiffeners and test the arms’ load-carrying capability.

“Extensive upgrades ahead of this flight test have been made to hardware and software across Super Heavy, Starship, and the launch and catch tower infrastructure at Starbase,” SpaceX said. “SpaceX engineers have spent years preparing and months testing for the booster catch attempt, with technicians pouring tens of thousands of hours into building the infrastructure to maximize our chances for success.”

It will take about seven minutes for the Super Heavy booster to climb to the edge of space, separate from the Starship upper stage, and return to Starbase for recovery. While the booster comes back to the ground, Starship will fire its six engines to accelerate to near orbital velocity, fast enough to complete a half-lap around Earth before gravity pulls it toward an atmospheric reentry over the Indian Ocean.

This is a similar trajectory to the one Starship flew in June, when it survived a fiery reentry for a controlled splashdown. It was the first time SpaceX completed an end-to-end Starship test flight.

After analyzing the results from the June mission, SpaceX engineers decided to rework the heat shield for the next Starship vehicle. The company said its technicians spent more than 12,000 hours replacing the entire thermal protection system with new-generation tiles, a backup ablative layer, and additional protections between the ship’s flap structures.

Onboard cameras showed fragments of the heat shield falling off Starship when it reentered the atmosphere in June.

“This massive effort, along with updates to the ship’s operations and software for reentry and landing burn, will look to improve upon the previous flight and bring Starship to a soft splashdown at the target area in the Indian Ocean,” SpaceX said.

Starship won’t attempt to reignite its Raptor engines in space on the upcoming test flight. This is one of the next things SpaceX needs to demonstrate for Starship to soar into a stable orbit around Earth and guide itself to a controlled reentry to ensure it doesn’t become stranded in space or fall over a populated area. SpaceX wanted to relight a Raptor engine in space on Starship’s third test flight in March, but aborted the maneuver.

The business end of Starship’s Super Heavy booster during a launch in March. Credit: SpaceX

Once Starship is able to sustain a flight in low-Earth orbit, SpaceX can begin experiments with in-space refueling, which is required to support future Starship flights to the Moon, Mars, and other deep space destinations. Starship is a foundational element of SpaceX’s vision to create a settlement on the red planet.

NASA has a contract with SpaceX to develop a human-rated Starship to land astronauts on the Moon as part of the agency’s Artemis program. NASA’s official schedule calls for the first Artemis crew landing in September 2026. Realistically, the landing will probably happen later in the decade because the Starship lander and new lunar spacesuits likely won’t be ready in two years.

Starships will likely fly many dozens of times, if not more, before NASA approves it to land astronauts on the Moon. These flights will test the rocket’s ability to repeatedly and reliably fly to space and back, transfer cryogenic propellants in orbit, and safely land on the lunar surface without a crew.

As we’ve seen with SpaceX’s workhorse Falcon 9 rocket, rapidly reusing elements of a launch vehicle can enable rapid-fire launch cadences. Validating the architecture for recovering the Super Heavy booster directly on the launch pad, as SpaceX intends to do quite soon, is a key step on this path.

Stephen Clark is a space reporter at Ars Technica, covering private space companies and the world’s space agencies. Stephen writes about the nexus of technology, science, policy, and business on and off the planet.

SpaceX’s next Starship launch—and first catch—could happen this weekend Read More »

SpaceX launches Europe’s Hera asteroid mission ahead of Hurricane Milton

asteroid, Commercial space, Dart, european space agency, falcon 9, Federal Aviation Administration, hera, launch, planetary defense, Science, Space, spacex / Rejus Almole / October 7, 2024

The launch of another important mission, NASA’s Europa Clipper, is on hold due to Hurricane Milton.

The European Space Agency’s Hera spacecraft flies away from the Falcon 9 rocket’s upper stage a little more than an hour after liftoff Monday. Credit: SpaceX

Two years ago, a NASA spacecraft smashed into a small asteroid millions of miles from Earth to test a technique that could one day prove useful to deflect an object off a collision course with Earth. The European Space Agency launched a follow-up mission Monday to go back to the crash site and see the damage done.

The nearly $400 million (363 million euro) Hera mission, named for the Greek goddess of marriage, will investigate the aftermath of a cosmic collision between NASA’s DART spacecraft and the skyscraper-size asteroid Dimorphos on September 26, 2022. NASA’s Double Asteroid Redirection Test mission was the first planetary defense experiment, and it worked, successfully nudging Dimorphos off its regular orbit around a larger companion asteroid named Didymos.

But NASA had to sacrifice the DART spacecraft in the deflection experiment. Its destruction meant there were no detailed images of the condition of the target asteroid after the impact. A small Italian CubeSat deployed by DART as it approached Dimorphos captured fuzzy long-range views of the collision, but Hera will perform a comprehensive survey when it arrives in late 2026.

“We are going to have a surprise to see what Dimorphos looks like, which is, first, scientifically exciting, but also important because if we want to validate the technique and validate the model that can reproduce the impact, we need to know the final outcome,” said Patrick Michel, principal investigator on the Hera mission from Côte d’Azur Observatory in Nice, France. “And we don’t have it. With Hera, it’s like a detective going back to the crime scene and telling us what really happened.”

Last ride before the storm

The Hera spacecraft, weighing in at 2,442 pounds (1,108 kilograms), lifted off on top of a SpaceX Falcon 9 rocket at 10: 52 am EDT (14: 52 UTC) Monday from Cape Canaveral Space Force Station, Florida.

Officials weren’t sure the weather conditions at Cape Canaveral would permit a launch Monday, with widespread rain showers and a blanket of cloud cover hanging over Florida’s Space Coast. But the conditions were just good enough to be acceptable for a rocket launch, and the Falcon 9 lit its nine kerosene-fueled engines to climb away from pad 40 after a smooth countdown.

SpaceX’s Falcon 9 rocket lifts off from Cape Canaveral Space Force Station, Florida, with ESA’s Hera mission. Credit: SpaceX

This was probably the final opportunity to launch Hera before the spaceport shutters in advance of Hurricane Milton, a dangerous Category 5 storm taking aim at the west coast of Florida. If the mission didn’t launch Monday, SpaceX was prepared to move the Falcon 9 rocket and the Hera spacecraft back inside a hangar for safekeeping until the storm passes.

Meanwhile, at NASA’s Kennedy Space Center a few miles away, SpaceX is securing a Falcon Heavy rocket with the Europa Clipper spacecraft to ride out Hurricane Milton inside a hangar at Launch Complex 39A. Europa Clipper is a $5.2 billion flagship mission to explore Jupiter’s most enigmatic icy moon, and it was supposed to launch Thursday, the same day Hurricane Milton will potentially move over Central Florida.

NASA announced Sunday that it is postponing Europa Clipper’s launch until after the storm.

“The safety of launch team personnel is our highest priority, and all precautions will be taken to protect the Europa Clipper spacecraft,” said Tim Dunn, senior launch director at NASA’s Launch Services Program. “Once we have the ‘all-clear’ followed by facility assessment and any recovery actions, we will determine the next launch opportunity for this NASA flagship mission.”

Europa Clipper must launch by November 6 in order to reach Jupiter and its moon Europa in 2030. ESA’s Hera mission had a similarly tight window to get off the ground in October and arrive at asteroids Didymos and Dimorphos in December 2026.

Returning to flight

The Falcon 9 did its job Monday, accelerating the Hera spacecraft to a blistering speed of 26,745 mph (43,042 km/hr) with successive burns by its first stage booster and upper stage engine. This was the highest-speed payload injection ever achieved by SpaceX.

SpaceX did not attempt to recover the Falcon 9’s reusable booster on Monday’s flight because Hera needed all of the rocket’s oomph to gain enough speed to escape the pull of Earth’s gravity.

“Good launch, good orbit, and good payload deploy,” wrote Kiko Dontchev, SpaceX’s vice president of launch, on X.

This was the first Falcon 9 launch in nine days—an unusually long gap between SpaceX missions—after the rocket’s upper stage misfired during a maneuver to steer itself out of orbit following an otherwise successful launch September 28 with a two-man crew heading for the International Space Station.

The upper stage engine apparently “over-burned,” and the rocket debris fell into the atmosphere short of its expected reentry corridor in the Pacific Ocean, sources said. The Federal Aviation Administration grounded the Falcon 9 rocket while SpaceX investigates the malfunction, but the FAA granted approval for SpaceX to launch the Hera mission because its trajectory would carry the rocket away from Earth, rather than back into the atmosphere for reentry.

“The FAA has determined that the absence of a second stage reentry for this mission adequately mitigates the primary risk to the public in the event of a reoccurrence of the mishap experienced with the Crew-9 mission,” the FAA said in a statement.

Members of the Hera team from ESA and its German prime contractor, OHB, pose with the spacecraft inside SpaceX’s payload processing facility in Florida. Credit: SpaceX

This was the third time the FAA has grounded SpaceX’s Falcon 9 rocket fleet in less than three months, following another upper stage failure in July that caused the destruction of 20 Starlink Internet satellites and the crash-landing of a Falcon 9 booster on an offshore drone ship in August. Federal regulators are responsible for ensuring commercial rocket launches don’t endanger the public.

These were the first major anomalies on any Falcon 9 launch since 2021.

It’s not clear when the FAA will clear SpaceX to resume launching other Falcon 9 missions. However, the launch of the Europa Clipper mission on a Falcon Heavy rocket, which uses essentially the same upper stage as a Falcon 9, is not licensed by the FAA because it is managed by NASA, another government agency. NASA will have final authority on whether to give the green light for the launch of Europa Clipper.

Surveying the damage

ESA’s Hera spacecraft is on course for a flyby of Mars next March to take advantage of the red planet’s gravity to slingshot itself on a trajectory to intercept its twin target asteroids. Near Mars, Hera will zoom relatively close to the planet’s asteroid-like moon, Deimos, to obtain rare closeups.

Then, Hera will approach Didymos and Dimorphos a little more than two years from now, maneuvering around the binary asteroid system at a range of distances, eventually moving as close as about a half-mile (1 kilometer) away.

Italy’s LICIACube spacecraft snapped this image of asteroids Didymos (lower left) and Dimorphos (upper right) a few minutes after the impact of DART on September 26, 2022. Credit: ASI/NASA

Dimorphos orbits Didymos once every 11 hours and 23 minutes, roughly 32 minutes shorter than the orbital period before DART’s impact in 2022. This change in orbit proved the effectiveness of a kinetic impactor in deflecting an asteroid that threatens Earth.

Dimorphos, the smaller of the two asteroids, has a diameter of around 500 feet (150 meters), while Didymos measures approximately a half-mile (780 meters) wide. Neither asteroid poses a risk to Earth, so NASA chose them as the objective for DART.

The Hubble Space Telescope spotted a debris field trailing the binary asteroid system after DART’s impact. Astronomers identified at least 37 boulders drifting away from the asteroids, material ejected when the DART spacecraft slammed into Dimorphos at a velocity of 14,000 mph (22,500 kmh).

Scientists will use Hera, with its suite of cameras and instruments, to study how the strike by DART changed the asteroid Dimorphos. Did the impact leave a crater, or did it reshape the entire asteroid? There are “tentative hints” that the asteroid’s shape changed after the collision, according to Michael Kueppers, Hera’s project scientist at ESA.

“If this is the case, it would also mean that the cohesion of Dimorphos is extremely low; that indeed, even an object the size of Dimorphos would be held together by its weight, by its gravity, and not by cohesion,” Kueppers said. “So it really would be a rubble pile.”

Hera will also measure the mass of Dimorphos, something DART was unable to do. “That is important to measure the efficiency of the impact… which was the momentum that was transferred from the impacting satellite to the asteroid,” Kueppers said.

This NASA/ESA Hubble Space Telescope image of the asteroid Dimorphos was taken on December 19, 2022, nearly three months after the asteroid was impacted by NASA’s DART mission. Hubble’s sensitivity reveals a few dozen boulders knocked off the asteroid by the force of the collision. Credit: NASA, ESA, D. Jewitt (UCLA)

The central goal of Hera is to fill the gaps in knowledge about Didymos and Dimorphos. Precise measurements of DART’s momentum, coupled with a better understanding of the interior structure of the asteroids, will allow future mission planners to know how best to deflect a hazardous object threatening Earth.

“The third part is to generally investigate the two asteroids to know their physical properties, their interior properties, their strength, essentially to be able to extrapolate or to scale the outcome of DART to another impact should we really need it one day,” Kueppers said.

Hera will release two briefcase-size CubeSats, named Juventas and Milani, to work in concert with ESA’s mothership. Juventas carries a compact radar to probe the internal structure of the smaller asteroid and will eventually attempt a landing on Dimorphos. Milani will study the mineral composition of individual boulders around DART’s impact site.

“This is the first time that we send a spacecraft to a small body, which is actually a multi-satellite system, with one main spacecraft and two CubeSats doing closer proximity operations,” Michel said. “This has never been done.”

Artist’s illustration of the Hera spacecraft with its two deployable CubeSats, Juventas and Milani, in the vicinity of the Didymos binary asteroid system. The CubeSats will communicate with ground teams via radio links with the Hera mothership. Credit: ESA-Science Office

One source of uncertainty, and perhaps worry, about the environment around Didymos and Dimorphos is the status of the debris field observed by Hubble a few months after DART’s impact. But this is not likely to be a problem, according to Kueppers.

“I’m not really worried about potential boulders at Didymos,” he said, recalling the relative ease with which ESA’s Rosetta spacecraft navigated around an active comet from 2014 through 2016.

Ignacio Tanco, ESA’s flight director for Hera, doesn’t share Kuepper’s optimism.

“We didn’t hit the comet with a hammer,” said Tanco, who is responsible for keeping the Hera spacecraft safe. “The debris question for me is actually a source of… I wouldn’t say concern, but certainly precaution. It’s something that we’ll need to approach carefully once we get there.”

“That’s the difference between an engineer and a scientist,” Kuepper joked.

Scientists originally wanted Hera to be in the vicinity of the Didymos binary asteroid system before DART’s arrival, allowing it to directly observe the impact and its fallout. But ESA’s member states did not approve funding for the Hera mission in time, and the space agency only signed the contract to build the Hera spacecraft in 2020.

ESA first studied a mission like DART and Hera more than 20 years ago, when scientists proposed a mission called Don Quijote to get an asteroid deflection. But other missions took priority in Europe’s space program. Now, Hera is on course to write the final chapter of the story of humanity’s first planetary defense test.

“This is our contribution of ESA to humanity to help us in the future protect our planet,” said Josef Aschbacher, ESA’s director general.

SpaceX launches Europe’s Hera asteroid mission ahead of Hurricane Milton Read More »

SCOTUS denial ends saga of Shkreli’s infamous 5,000% drug price scheme

daraprim, drug pricing, health, Marin Shkreli, Policy, Science, Shkreli / Kris Guyer / October 7, 2024

The legal saga over Martin Shkreli’s infamous 5,000 percent price hike of a life-saving anti-parasitic drug has ended with a flat denial from the highest court in the land.

On Monday, the Supreme Court rejected Shkreli’s petition to appeal an order to return $64.6 million in profits from the pricing scheme of Daraprim, a decades-old drug used to treat toxoplasmosis. The condition is caused by a single-celled parasite that can be deadly for newborns and people with compromised immune systems, such as people who have HIV, cancer, or an organ transplant.

Federal prosecutors successfully argued in courts that Shkreli orchestrated an illegal anticompetitive scheme that allowed him to dramatically raise the price of Daraprim overnight. When Shkreli and his pharmaceutical company, Vyera (formerly Turing), bought the rights to the drug in 2015, the price of a single pill jumped to $750 after being priced between $13.50 and $17.50 earlier that year. And Shkreli quickly came to epitomize callous greed in the pharmaceutical industry.

In a lawsuit filed in 2021, the Federal Trade Commission and seven state attorneys general accused Shkreli of building a “web of anticompetitive restrictions to box out the competition.” In January of 2022, US District Court Judge Denise Cote agreed, finding that Shkreli’s conduct was “egregious, deliberate, repetitive, long-running, and ultimately dangerous.”

SCOTUS denial ends saga of Shkreli’s infamous 5,000% drug price scheme Read More »

Medicine Nobel goes to previously unknown way of controlling genes

Biology, evolution, gene regulation, microRNA, Nobel prize, Science / Tim Belzer / October 7, 2024

Based on the stereotypical hairpin structure, researchers have scanned genomes and found over 38,000 likely precursors; nearly 50,000 mature microRNAs have been discovered by sequencing all the RNA found in cells from a variety of species. While found widely in animals, they’ve also been discovered in plants, raising the possibility that they existed in a single-celled ancestral organism.

While some microRNA genes, including lin-4 and let-7, have dramatic phenotypes when mutated, many have weak or confusing effects. This is likely in part due to the fact that a single microRNA can bind to and regulate a variety of genes and so may have a mix of effects when mutated. In other cases, several different microRNAs may bind to the same messenger RNA, creating a redundancy that makes the loss of a single microRNA difficult to detect.

Nevertheless, there’s plenty of evidence that, collectively, they’re essential for normal development in many organisms and tissues. Knocking out the gene that encodes the Dicer protein, which is needed for forming mature microRNAs, causes early embryonic lethality. Knockouts of the gene in specific cell types cause a variety of defects. For example, B cells never mature if Dicer is lost in that cell lineage, and a knockout in nerve cells causes microcephaly and limiting branching of connections among neurons, leading the animals to die shortly after birth.

This being the Medicine prize, the Nobel Committee also cite a number of human genetic diseases that are caused by mutations in microRNA genes.

Overall, the award highlights just how complex life is at the cellular level. There’s a fair number of genes that have to be made by every cell simply to enable their survival. But as for the rest, they exist embedded in complex regulatory networks that interact to ensure that proteins are made only where and when they’re needed, and often degraded if they somehow get made anyway. And every now and then, fundamental research in an oddball species is still telling us unexpected things about those networks.

Medicine Nobel goes to previously unknown way of controlling genes Read More »

Hurricane Milton becomes second-fastest storm to reach Category 5 status

milton, Science, science.hurricanes, tampa bay / Mike M. / October 7, 2024

Tampa in the crosshairs

The Tampa Bay metro area, with a population of more than 3 million people, has grown into the most developed region on the west coast of Florida. For those of us who follow hurricanes, this region has stood out in recent years for a preternatural ability to dodge large and powerful hurricanes. There have been some close calls to be sure, especially of late with Hurricane Ian in 2022, and Hurricane Helene just last month.

But the reality is that a major hurricane, defined as Category 3 or larger on the Saffir-Simpson Scale, has not made a direct impact on Tampa Bay since 1921.

It remains to be seen what precisely happens with Milton. The storm should reach its peak intensity over the course of the next day or so. At some point Milton should undergo an eyewall replacement cycle, which leads to some weakening. In addition, the storm is likely to ingest dry air from its west and north as a cold front works its way into the northern Gulf of Mexico. (This front is also responsible for Milton’s odd eastward track across the Gulf, where storms more commonly travel from east to west.)

11 am ET Monday track forecast for Hurricane Milton. Credit: National Hurricane Center

So by Wednesday, at the latest, Milton should be weakening as it approaches the Florida coast. However, it will nonetheless be a very large and powerful hurricane, and by that point the worst of its storm surge capabilities will already be baked in—that is, the storm surge will still be tremendous regardless of whether Milton weakens.

By Wednesday evening a destructive storm surge will be crashing into the west coast of Florida, perhaps in Tampa Bay, or further to the south, near Fort Meyers. A broad streak of wind gusts above 100 mph will hit the Florida coast as well, and heavy rainfall will douse much of the central and northern parts of the state.

For now, Milton is making some history by rapidly strengthening in the Gulf of Mexico. By the end of this week, it will very likely become historic for the damage, death, and destruction in its wake. If you live in affected areas, please heed evacuation warnings.

Hurricane Milton becomes second-fastest storm to reach Category 5 status Read More »

Greening of Antartica shows how climate change affects the frozen continent

Antarctica, climate change, Science, syndication / Mike M. / October 6, 2024

Plant growth is accelerating on the Antarctic Peninsula and nearby islands.

Moss and rocks cover the ground on Robert Island in Antarctica. Photographer: Isadora Romero/Bloomberg Credit: Bloomberg via Getty

When satellites first started peering down on the craggy, glaciated Antarctic Peninsula about 40 years ago, they saw only a few tiny patches of vegetation covering a total of about 8,000 square feet—less than a football field.

But since then, the Antarctic Peninsula has warmed rapidly, and a new study shows that mosses, along with some lichen, liverworts and associated algae, have colonized more than 4.6 square miles, an area nearly four times the size of New York’s Central Park.

The findings, published Friday in Nature Geoscience, based on a meticulous analysis of Landsat images from 1986 to 2021, show that the greening trend is distinct from natural variability and that it has accelerated by 30 percent since 2016, fast enough to cover nearly 75 football fields per year.

Greening at the opposite end of the planet, in the Arctic, has been widely studied and reported, said co-author Thomas Roland, a paleoecologist with the University of Exeter who collects and analyzes mud samples to study environmental and ecological change. “But the idea,” he said, “that any part of Antarctica could, in any way, be green is something that still really jars a lot of people.”

illustration of Antarctica and satellite photos — Credit: Inside Climate News

As the planet heats up, “even the coldest regions on Earth that we expect and understand to be white and black with snow, ice, and rock are starting to become greener as the planet responds to climate change,” he said.

The tenfold increase in vegetation cover since 1986 “is not huge in the global scheme of things,” Roland added, but the accelerating rate of change and the potential ecological effects are significant. “That’s the real story here,” he said. “The landscape is going to be altered partially because the existing vegetation is expanding, but it could also be altered in the future with new vegetation coming in.”

In the Arctic, vegetation is expanding on a scale that affects the albedo, or the overall reflectivity of the region, which determines the proportion of the sun’s heat energy that is absorbed by the Earth’s surface as opposed to being bounced away from the planet. But the spread of greenery has not yet changed the albedo of Antarctica on a meaningful scale because the vegetated areas are still too small to have a regional impact, said co-author Olly Bartlett, a University of Hertfordshire researcher who specializes in using satellite data to map environmental change.

“The real significance is about the ecological shift on the exposed land, the land that’s ice-free, creating an area suitable for more advanced plant life or invasive species to get a foothold,” he said.

Bartlett said Google Earth Engine enabled the scientists to process a massive amount of data from the Landsat images to meet a high standard of verification of plant growth. As a result, he added, the changes they reported may actually be conservative.

“It’s becoming easier for life to live there,” he said. “These rates of change we’re seeing made us think that perhaps we’ve captured the start of a more dramatic transformation.”

In the areas they studied, changes to the albedo could have a small local effect, Roland said, as more land free of reflective ice “can feed into a positive feedback loop that creates conditions that are more favorable for vegetation expansion as well.”

Antarctic forests at similar CO₂ levels

Other research, including fossil studies, suggests that beech trees grew on Antarctica as recently as 2.5 million years ago, when carbon dioxide levels in the atmosphere were similar to today, another indicator of how unchecked greenhouse gas emissions can rapidly warm Earth’s climate.

Currently, there are only two species of flowering plants native to the Antarctic Peninsula, Antarctic hair grass, and Antarctic pearlwort. “But with a few new grass seeds here and there, or a few spores, and all of a sudden, you’ve got a very different ecosystem,” he said.

And it’s not just plants, he added. “Increasingly, we’re seeing evidence that non-native insect life is taking hold in Antarctica. And that can dramatically change things as well.”

The study shows how climate warming will shake up Antarctic ecosystems, said conservation scientist Jasmine Lee, a research fellow with the British Antarctic Survey who was not involved in the new study.

“It is clear that bank-forming mosses are expanding their range with warmer and wetter conditions, which is likely facilitating similar expansions for some of the invertebrate communities that rely on them for habitat,” she said. “At the same time, some specialist species, such as the more dry-loving mosses and invertebrates, might decline.”

She said the new study is valuable because it provides data across a broad region showing that Antarctic ecosystems are already rapidly altering and will continue to do so as climate change progresses.

“We focus a lot on how climate change is melting ice sheets and changing sea ice,” she said. “It’s good to also highlight that the terrestrial ecosystems are being impacted.”

The study shows climate impacts growing in “regions previously thought nearly immune to the accelerated warming we’re seeing today,” said climate policy expert Pam Pearson, director of the International Cryosphere Climate Initiative.

“It’s as important a signal as the loss of Antarctic sea ice over the past several years,” she said.

The new study identified vegetative changes by comparing the Landsat images at a resolution of 300-square-feet per pixel, detailed enough to accurately map vegetative growth, but it didn’t identify specific climate change factors that might be driving the expansion of plant life.

But other recent studies have documented Antarctic changes that could spur plant growth, including how some regions are affected by warm winds and by increasing amounts of rain from atmospheric rivers, as well as by declining sea ice that leads adjacent land areas to warm, all signs of rapid change in Antarctica.

Roland said their new study was in part spurred by previous research showing how fast patches of Antarctic moss were growing vertically and how microbial activity in tiny patches of soil was also accelerating.

“We’d taken these sediment cores, and done all sorts of analysis, including radiocarbon dating … showing the growth in the plants we’d sampled increasing dramatically,” he said.

Those measurements confirmed that the plants are sensitive to climate change, and as a next step, researchers wanted to know “if the plants are growing sideways at the same dramatic rate,” he said. “It’s one thing for plants to be growing upwards very fast. If they’re growing outwards, then you know you’re starting to see massive changes and massive increases in vegetation cover across the peninsula.”

With the study documenting significant horizontal expansion of vegetation, the researchers are now studying how recently deglaciated areas were first colonized by plants. About 90 percent of the glaciers on the Antarctic Peninsula have been shrinking for the past 75 years, Roland said.

“That’s just creating more and more land for this potentially rapid vegetation response,” he said. “So like Olly says, one of the things we can’t rule out is that this really does increase quite dramatically over the next few decades. Our findings raise serious concerns about the environmental future of the Antarctic Peninsula and of the continent as a whole.”

This story originally appeared on Inside Climate News.

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