June 5, 20254 min readThe Trump-Musk Fight Could Have Huge Consequences for U.S. Space ProgramsA vitriolic war of words between President Donald Trump and SpaceX CEO Elon Musk could have profound repercussions for the nation’s civil and military space programsBy Lee Billings edited by Dean VisserElon Musk (left) and President Donald Trump (right) seemed to be on good terms during a press briefing in the Oval Office at the White House on May 30, 2025, but the event proved to be the calm before a social media storm. Kevin Dietsch/Getty ImagesFor several hours yesterday, an explosively escalating social media confrontation between arguably the world’s richest man, Elon Musk, and the world’s most powerful, President Donald Trump, shook U.S. spaceflight to its core.The pair had been bosom-buddy allies ever since Musk’s fateful endorsement of Trump last July—an event that helped propel Trump to an electoral victory and his second presidential term. But on May 28 Musk announced his departure from his official role overseeing the U.S. DOGE Service. And on May 31 the White House announced that it was withdrawing Trump’s nomination of Musk’s close associate Jared Isaacman to lead NASA. Musk abruptly went on the attack against the Trump administration, criticizing the budget-busting One Big Beautiful Bill Act, now navigating through Congress, as “a disgusting abomination.”Things got worse from there as the blowup descended deeper into threats and insults. On June 5 Trump suggested on his own social-media platform, Truth Social, that he could terminate U.S. government contracts with Musk’s companies, such as SpaceX and Tesla. Less than an hour later, the conflict suddenly grew more personal, with Musk taking to X, the social media platform he owns, to accuse Trump—without evidence—of being incriminated by as-yet-unreleased government documents related to the illegal activities of convicted sex offender Jeffrey Epstein.On supporting science journalismIf you're enjoying this article, consider supporting our award-winning journalism by subscribing. By purchasing a subscription you are helping to ensure the future of impactful stories about the discoveries and ideas shaping our world today.Musk upped the ante further in follow-up posts in which he endorsed a suggestion for impeaching Trump and, separately, declared in a now deleted post that because of the president’s threat, SpaceX “will begin decommissioning its Dragon spacecraft immediately.” (Some five hours after his decommissioning comment, tempers had apparently cooled enough for Musk to walk back the remark in another X post: “Ok, we won’t decommission Dragon.”)Dragon is a crucial workhorse of U.S. human spaceflight. It’s the main way NASA’s astronauts get to and from the International Space Station (ISS) and also a key component of a contract between NASA and SpaceX to safely deorbit the ISS in 2031. If Dragon were to be no longer be available, NASA would, in the near term, have to rely on either Russian Soyuz vehicles or on Boeing’s glitch-plagued Starliner spacecraft for its crew transport—and the space agency’s plans for deorbiting the ISS would essentially go back to the drawing board. More broadly, NASA uses SpaceX rockets to launch many of its science missions, and the company is contracted to ferry astronauts to and from the surface of the moon as part of the space agency’s Artemis III mission.Trump’s and Musk’s retaliatory tit for tat also raises the disconcerting possibility of disrupting other SpaceX-centric parts of U.S. space plans, many of which are seen as critical for national security. Thanks to its wildly successful reusable Falcon 9 and Falcon Heavy rockets, the company presently provides the vast majority of space launches for the Department of Defense. And SpaceX’s constellation of more than 7,000 Starlink communications satellites has become vitally important to war fighters in the ongoing conflict between Russia and U.S.-allied Ukraine. SpaceX is also contracted to build a massive constellation of spy satellites for the DOD and is considered a leading candidate for launching space-based interceptors envisioned as part of Trump’s “Golden Dome” missile-defense plan.Among the avalanche of reactions to the incendiary spectacle unfolding in real time, one of the most extreme was from Trump’s influential former adviser Steve Bannon, who called on the president to seize and nationalize SpaceX. And in an interview with the New York Times, Bannon, without evidence, accused Musk, a naturalized U.S. citizen, of being an “illegal alien” who “should be deported from the country immediately.”NASA, for its part, attempted to stay above the fray via a carefully worded late-afternoon statement from the space agency’s press secretary Bethany Stevens: “NASA will continue to execute upon the President’s vision for the future of space,” Stevens wrote. “We will continue to work with our industry partners to ensure the President’s objectives in space are met.”The response from the stock market was, in its own way, much less muted. SpaceX is not a publicly traded company. But Musk’s electric car company Tesla is. And it experienced a massive sell-off at the end of June 5’s trading day: Tesla’s share price fell down by 14 percent, losing the company a whopping $152 billion of its market value.Today a rumored détente phone conversation between the two men has apparently been called off, and Trump has reportedly said he now intends to sell the Tesla he purchased in March in what was then a gesture of support for Musk. But there are some signs the rift may yet heal: Musk has yet to be deported; SpaceX has not been shut down; Tesla’s stock price is surging back from its momentary heavy losses; and it seems NASA astronauts won’t be stranded on Earth or on the ISS for the time being.Even so, the entire sordid episode—and the possibility of further messy clashes between Trump and Musk unfolding in public—highlights a fundamental vulnerability at the heart of the nation’s deep reliance on SpaceX for access to space. Outsourcing huge swaths of civil and military space programs to a disruptively innovative private company effectively controlled by a single individual certainly has its rewards—but no shortage of risks, too.

RoboCop: Rogue City – Unfinished Business preview: ‘We created something bigger than we expected’ Adam Starkey Published June 3, 2025 9:00am Stay out of trouble (Nacon) GameCentral goes hands-on with the standalone expansion of RoboCop: Rogue City, which dials up the action and gory splatter of 2023’s surprise hit. For a franchise that has arguably done nothing of worth since the early 90s, the future of RoboCop is looking surprisingly bright. Following Amazon’s acquisition of MGM, a new TV show is currently in the works, with rumbles of a new film as well. Whether this leads to a major rejuvenation for everyone’s favourite cyborg law enforcer remains to be seen, but the original source of any RoboCop redemption arc has to start with 2023’s RoboCop: Rogue City.  Developed by Polish studio Teyon, RoboCop: Rogue City was the kind of unexpected surprise you rarely get from licensed games. It recaptured the original’s wit and 80s aesthetic, but also found a way to deliver the fantasy of playing as the half-human cyborg without streamlining any of the character’s personality. The bloody action was built around his hulking, slow movement, dry one-liners were in abundance, and missions weren’t always reduced to mowing down thugs in corridors – you also handed people parking tickets, settled trivial civilian disputes, and, in one wonderfully mundane side mission, did the rounds in the office for a get well card.  The game became publisher Nacon’s ‘best ever launch’ with 435,000 players within two weeks. Now, a year and a half later, developer Teyon is back with a standalone expansion. Marketing around Unfinished Business has purposefully dodged the term *DLC*, but as explained by the studio’s communications manager, Dawid Biegun, it started out as exactly that.  ‘When we released RoboCop: Rogue City, we were thinking about, this story has many things [we can] do in the future,’ says Biegun. ‘We had many paths we could choose. So we basically started slowly developing some new storyline. The game was planned to be DLC but it grew out of control. It was a really rare situation where we created something bigger than we expected, so it became a standalone expansion from then.’ Unlike Rogue City, this expansion, which we’re told spans around eight hours on average, is centred around one location in the OmniTower. Like most things in the RoboCop realm created by OCP, this promised idyllic housing complex quickly goes south when a band of mercenaries assume control. To restore order, and after a creepy opening where an attack on the Detroit police station leaves several officers frozen solid, RoboCop is assigned to the case.  RoboCop has new moves at his disposal (Nacon) Unfinished Business wastes little time in throwing you into the action, and quickly amps up the chaos. For anyone who has played Rogue City, all the original tenets of the combat are here, albeit with a slight increase in difficulty. You’ll be looking for explosive cans to blast, illuminated panels to ricochet bullets off walls, and all the while trying not to expose yourself to too much gunfire. The combat purposefully doesn’t have the slick speed of Call Of Duty, but it is still aggressively punchy, with headshots resulting in satisfyingly bloody splatters and RoboCop’s famed Auto-9 machine pistol still having the kickback of a pocket pneumatic drill.  From the get-go, Unfinished Business pushes back in a way Rogue City never did. New enemies equipped with riot shields are a real nuisance if you don’t utilise the ricochet panels, while the ability to slow down time is a much bigger crutch to chip down the enemy numbers from a distance. Health pick-ups felt in shorter supply too, even on the normal difficulty, to the point where we barely scraped through several encounters.  While it’s unclear if this applies to the whole game, Unfinished Business feels like a gnarlier experience, when compared to the original. RoboCop has some new context sensitive finishing moves, like throwing enemy heads into concrete walls or vending machines, which is a satisfying addition to the melee arsenal. There’s greater enemy variety too, between fierce minigun heavyweights and flying drones, along with some neat action set pieces. In one standout, we had to operate a walkway bridge to deactivate a giant turret at the end of a room, dashing between cover as it rains down bullets and destroys the surrounding environment. Anyone who has played action games before will recognise all the mechanics at play in this scenario, but it was still well executed and effective. Another had a whiff of Star Wars, as you rush around shooting electrical panels to stop a trash compactor from crushing you via the descending ceiling. The action shift in Unfinished Business is best defined by a later sequence we got to play, where you take control of the franchise’s signature mech, ED-209. If the power fantasy of playing as RoboCop is tested in this expansion, ED-209’s section was pure mental catharsis, where you blast away enemy hordes with miniguns and rockets, and clean up any stragglers with a rigid, robotic stomp. The rush of piloting ED-209, with its cacophony of explosions and bullets, felt like a throwback to vehicle sections in a long lost Xbox 360 game – but in a good way.  While there’s a definite lean towards combat, rather than gift card signing, when compared to Rogue City, it hasn’t entirely abandoned the detective side. According to the developers, if Rogue City had a 60/40 percent split between guns and detective work, Unfinished Business ‘would be like 70/30, or 80/20’ in comparison. More Trending We saw some of this , with one memorable encounter seeing you quizzed by a RoboCop superfan who is unconvinced you’re the actual RoboCop, leading to a series of questions based on the history of the franchise. There is optional side missions too, although the time we had with our preview limited our chance to fully delve into them. The sales and positive reviews for RoboCop: Rogue City emboldened Teyon’s vision and scope for Unfinished Business – and that confidence shines through in what we played. Some might be disappointed by the steer towards action, and we were heading into this preview, but by the end, this felt like a welcome extension with its own unique flavour. This is RoboCop: Rogue City with its pedal to the floor, confined and concentrated into a lean, tightly focused machine.  As for the studio’s next steps, the success of RoboCop has only reaffirmed Teyon’s strengths and identity as a team. Between its three studios across Poland and Japan, with over 140 employees in total, Teyon wants to maintain its grip within the AA space. ‘We feel strong here in such games,’ Biegun said. ‘We wouldn’t want to grow like 200, 300, 400 people, because we’re going to lose our soul this way. We want to stay as we are right now.’ ED-209 needs be wary of stairs (Nacon) Email gamecentral@metro.co.uk, leave a comment below, follow us on Twitter, and sign-up to our newsletter. To submit Inbox letters and Reader’s Features more easily, without the need to send an email, just use our Submit Stuff page here. For more stories like this, check our Gaming page. Arrow MORE: How to get a Nintendo Switch 2 this week in the UK GameCentral Sign up for exclusive analysis, latest releases, and bonus community content. This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply. Your information will be used in line with our Privacy Policy

HighPoint RocketStor 8631CW enables full PCIe Gen5 x16 GPU power externally with zero software, ideal for high-end mobile workflows like AI or 8K editing.

With yet another failed Starship test this week, in which the ambitious heavy rocket exploded once again, you might reasonably suspect that luck has finally run out for SpaceX. But this degree of failure during a development process isn’t actually unusual, according to Wendy Whitman Cobb, a space policy expert with the School of Advanced Air and Space Studies, especially when you’re testing new space technology as complex as a large rocket. However, the Starship tests are meaningfully different from the slow, steady pace of development that we’ve come to expect from the space sector.“The reason a lot of people perceive this to be unusual is that this is not the typical way that we have historically tested rockets,” Whitman Cobb says.Historically speaking, space agencies like NASA or legacy aerospace companies like United Launch Alliance (ULA) have taken their time with rocket development and have not tested until they were confident in a successful outcome. That’s still the case today with major NASA projects like the development of the Space Launch System (SLS), which has now dragged on for over a decade. “They will take as long as they need to to make sure that the rocket is going to work and that a launch is going to be successful,” Whitman Cobb says.“This is not the typical way that we have historically tested rockets.”SpaceX has chosen a different path, in which it tests, fails, and iterates frequently. That process has been at the heart of its success, allowing the company to make developments like the reusable Falcon 9 rocket at a rapid pace. However, it also means frequent and very public failures, which have generated complaints about environmental damage in the local area around the launch site and have caused the company to butt heads with regulatory agencies. There are also significant concerns about the political ties of CEO Elon Musk to the Trump administration and his undemocratic influence over federal regulation of SpaceX’s work.Even within the context of SpaceX’s move-fast-and-break-things approach, though, the development of the Starship has appeared chaotic. Compared to the development of the Falcon 9 rocket, which had plenty of failures but a generally clear forward path from failing often to failing less and less as time went on, Starship has a much more spotty record.Previous development was more incremental, first demonstrating that the rocket was sound before moving onto more complex issues like reusability of the booster or first stage. The company didn’t even attempt to save the booster of a Falcon 9 and reuse it until several years into testing.Starship isn’t like that. “They are trying to do everything at once with Starship,” Whitman Cobb says, as the company is trying to debut an entirely new rocket with new engines and make it reusable all at once. “It really is a very difficult engineering challenge.”“They are trying to do everything at once with Starship.”The Raptor engines that power the Starship are a particularly tough engineering nut to crack, as there are a lot of them — 33 per Starship, all clustered together — and they need to be able to perform the tricky feat of reigniting in space. The relighting of engines has been successful on some of the previous Starship test flights, but it has also been a point of failure.Why, then, is SpaceX pushing for so much, so fast? It’s because Musk is laser-focused on getting to Mars. And while it would theoretically be possible to send a mission to Mars using existing rockets like the Falcon 9, the sheer volume of equipment, supplies, and people needed for a Mars mission has a very large mass. To make Mars missions even remotely affordable, you need to be able to move a lot of mass in one launch — hence the need for a much larger rocket like the Starship or NASA’s SLS.NASA has previously been hedging its bets by developing its own heavy launch rocket as well as supporting the development of Starship. But with recent funding cuts, it’s looking more and more likely that the SLS will get axed — leaving SpaceX as the only player in town to facilitate NASA’s Mars plans. But there’s still an awful lot of work to do to get Starship to a place where serious plans for crewed missions can even be made. “There’s no way that they’re putting people on that right now.”Will a Starship test to Mars happen by 2026, with a crewed test to follow as soon as 2028, as Musk said this week he’s aiming for? “I think it’s completely delusional,” Whitman Cobb says, pointing out that SpaceX has not appeared to be seriously considering issues like adding life support to the Starship or making concrete plans for Mars habitats, launch and landing pads, or infrastructure. “I don’t see SpaceX as putting its money where its mouth is,” Whitman Cobb says. “If they do make the launch window next year, it’s going to be uncrewed. There’s no way that they’re putting people on that right now. And I seriously doubt whether they will make it.”That doesn’t mean Starship will never make it to Mars, of course. “I believe SpaceX will engineer their way out of it. I believe their engineering is good enough that they will make Starship work,” Whitman Cobb says. But getting an uncrewed rocket to Mars within the next decade is a lot more realistic than next year. Putting people on the rocket, though, is another matter entirely. “If they’re looking to build a large-scale human settlement? That’s decades,” Whitman Cobb says. “I don’t know that I will live to see that.”See More:

May 29, 20255 min readSpaceX’s Starbase Is Officially a City. Some Neighbors Aren’t ThrilledStarbase, SpaceX’s launch site turned company town in South Texas, faces local opposition from residents outside the city limitsBy Paola Rosa-Aquino edited by Lee BillingsSpaceX rockets stand near the end of a neighborhood street in the company’s Starbase launch complex in this photograph from October 2021. Starbase was officially incorporated as a city of Cameron County, Texas in May 2025. Mark Felix/Bloomberg via Getty ImagesBefore SpaceX’s Starship lost control and exploded over the Indian Ocean during its ninth test flight, the 400-foot-tall megarocket blasted off from Texas’s newest city.Starbase, situated on 1.5 square miles of the Lone Star State’s southernmost tip in the Rio Grande Valley, is mostly made up of SpaceX employees living on company-owned property and abuts a habitat for endangered wildlife, as well as a public beach.Starbase serves as the main testing and launch location for Starship, SpaceX’s planned fully reusable spacecraft, which is meant to revolutionize human and uncrewed space travel with its gargantuan payload capacity and rapid-fire flight cadence. If Starship’s development proceeds as planned, the megarocket could soon be ferrying crew and cargo alike to multiple otherworldly destinations—such as the lunar surface, for NASA’s Artemis program, and Mars, in fulfillment of SpaceX founder Elon Musk’s long-stated dream. But nearby residents worry about less glamorous local effects, fearing that a town built around the space company could continue SpaceX’s alleged pattern of polluting the area and blocking access to the nearby beach and other open public spaces.On supporting science journalismIf you're enjoying this article, consider supporting our award-winning journalism by subscribing. By purchasing a subscription you are helping to ensure the future of impactful stories about the discoveries and ideas shaping our world today.“SpaceX has already proven itself to be an extremely bad neighbor,” says Christopher Basaldú, an anthropologist and environmentalist and co-founder of the South Texas Environmental Justice Network, who lives in nearby Brownsville, Tex. SpaceX did not immediately respond to a request for comment.Long before it was Starbase, the area’s beaches, tidal flats and wetlands were of great significance to the Indigenous Carrizo/Comecrudo people (or Esto’k Gna in their own language). Many of them still live nearby as members of the modern-day Carrizo/Comecrudo Tribe of Texas. Today the area is largely Latino and among the poorest in the country. Musk’s space company began buying up property there in 2012; ever since company housing and rocket-related infrastructure have steadily sprouted.“We’ve grown quite a bit just in the last couple of years. It’s a couple hundred employees [and] their families, living amongst actual rockets,” said Daniel Huot, a SpaceX communications manager, during a company livestream before Tuesday’s Starship test flight.Huot added that the move to incorporate what was formerly Boca Chica Village as Starbase will help the company “scale more quickly [to] try to build out the best community possible for all the people that are building the future of humanity’s place in space.”Even before SpaceX began launching rockets at the site, neighbors complained about potential environmental woes stemming from the company’s operations. In a 2018 press conference, Musk dismissed such concerns, saying “We’ve got a lot of land with no one around, and so if [a rocket] blows up, it’s cool.”The first launch of the 40-story-tall Starship vehicle in April 2023 didn’t entirely proceed as planned—it blew up the concrete launch pad and left a literal crater behind. Particulate debris, as well as concrete and steel shrapnel from the botched launch, scattered far and wide across the surrounding landscape, igniting fires and slamming into protected habitats and public beaches. Ash, dust and sand grains hurled aloft by this first Starship flight test rained down as far out as Port Isabel, Tex., about five miles from the launch site.Local environmentalists have also sounded the alarm on how the company’s activities at Starbase could increase chemical and sonic pollution that puts migratory birds and other vulnerable endangered species in the area at greater risk.Despite these brewing tensions, Starbase was incorporated in early May, making it the first new city in Cameron County, Texas, in 30 years.Only people who live in the immediate area—almost all of them SpaceX employees—were eligible to vote for the new city. Residents voted 212 for and six against. The city’s mayor and commissioners—all current or former SpaceX employees—ran unopposed. “Now [SpaceX has] stolen away not only a neighborhood but the land around it, which had been basically environmentally untouched areas,” says Basaldú, who is a member of the Carrizo/Comecrudo Tribe.Starbase’s boundaries snake along State Highway 4, which provides the only access to both Starbase and the open-to-the-public Boca Chica Beach. A bill pending in the Texas Legislature would shift control over weekday closures of the beach and nearby roadways from the county commissioners to Starbase city leaders now that Starbase is a municipality under law.“As a community, we were there first,” says Suquiery Santillana, a resident of nearby Brownsville, Tex., who has visited Boca Chica Beach since childhood. “I’m almost 50, and now my grandkids are going.” Her family’s trips to the isolated shoreline now include wide-eyed roadside spectators from all across the country who want to catch a glimpse of the SpaceX launch site. While Santillana is happy that SpaceX has brought jobs to the area, she would like the company to communicate more about upcoming closures and launch plans with locals.Members of the Carrizo/Comecrudo Tribe also trace their creation story to this once-pristine beach. The intermittent access restrictions imposed by SpaceX’s launches, some tribe members say, limit them from freely participating in traditions such as fishing and tribal ceremonies that have been taking place on their ancestral land for thousands of years.Activity at the site could soon ramp up even more. On May 22 the Federal Aviation Administration (FAA) announced it had granted approval for SpaceX to increase the annual number of Starbase launches from five to 25. Eventually, Starship flights from the site could far exceed that because the vehicle is designed for very fast turnaround times and an unprecedentedly high launch cadence. Starship’s sheer size, coupled with more frequent launches, could balloon Starbase’s overall environmental footprint while also essentially shutting down Highway 4 for much of the year. The FAA did not immediately respond to a request for comment.For now, Starbase is poised to continue its rapid development and expansion, with plans in the works for more housing, offices and rocket launch facilities. Jim Chapman of the local environmental justice nonprofit Save RGV (Rio Grande Valley) worries that Starbase’s incorporation could allow SpaceX to skirt important regulatory hurdles. “[SpaceX has] fewer layers of bureaucracy that [it has] to go through and get approval from,” he says. “But on the other hand, I haven’t really seen the county denying [it] anything.”As SpaceX vies to fly ever more powerful rockets in pursuit of Musk’s interplanetary aspirations, local residents also fear that the company’s launch activity and its proximity to new natural gas projects could pose grave threats to Rio Grande Valley communities. One such project currently under construction is less than six miles from the launch site—too close for comfort, some critics say, given the possibility of volatile explosions sparked by showers of fiery rocket debris.If Musk’s latest projections are to be trusted (he often overpromises and underdelivers on meeting ambitious rocketry deadlines), additional Starship test flights will blast off from Starbase every few weeks for the rest of the summer. Time will tell if the company will be mindful of those who live next door.

here comes the boom! Falcon 9 sonic booms can feel more like seismic waves Trajectories, wind shear, temperature gradients, topography, and weather can affect how a sonic boom spreads. Jennifer Ouellette – May 27, 2025 12:36 pm | 1 A Falcon 9 rocket lifted SPHEREx into orbit in March. Credit: NASA/Jim Ross A Falcon 9 rocket lifted SPHEREx into orbit in March. Credit: NASA/Jim Ross Story text Size Small Standard Large Width * Standard Wide Links Standard Orange * Subscribers only   Learn more The Vandenberg Space Force Base in Santa Barbara, California, serves military space launch missions as well as launches for NASA and commercial entities like SpaceX. But how do all those launches affect residents living along the Central Coast? People might marvel at the spectacular visual display, but as launch activity at the base has ramped up, so have the noise complaints, particularly about the sonic booms produced by Falcon 9 launches, which can reach as far south as Ventura County. The booms rattle windows, frighten pets, and have raised concerns about threats to the structural integrity of private homes. There have been rockets launching from Vandenberg for decades, so why are the Falcon 9 launches of such concern? "Because of the Starlink satellites, the orbital mechanics for where they're trying to place these in orbit is bringing [the trajectories] closer to the coast," said Brigham Young University's Kent Gee, who described his research into sonic boom effects on neighboring communities in a press briefing at a meeting of the Acoustical Society of America in New Orleans. And the launches are occurring much more frequently, from two to three launches per year in the 1980s to between five and seven launches each month today. There were 46 Falcon 9 launches out of the Vandenberg base in 2024 alone, per Gee. Gee joined a project called ECOBOOM (Environmental and Community Observation of Sonic Booms) to study the factors that can impact just how jarring those sonic booms might be, conducted jointly by BYU and California State University, Bakersfield, with cooperation from the Space Force. "Space Force is interested in this because they feel a sense of stewardship," said Gee. "These rockets from SpaceX and other providers are launched from the base for a variety of missions and they want to understand the effects both on and off base, trying to understand how they can complete the mission while minimizing [negative] impacts." Gee and his cohorts monitored 132 separate sonic booms last summer, relying on data gathered via a network of 25 or so acoustic monitoring stations located along 500 square miles, including the beaches of Isla Vista and further inland to the hills of Ojai. "The measurements were made in parks, people's backyards, parking lots, wastewater plants, and all sorts of different locations," said Gee. More bang than boom A view of a Falcon 9 rocket launch from a park in Ventura County. Credit: Kent Gee There has been a great deal of research on supersonic aircraft, but the sonic booms produced by rockets like the Falcon 9 are acoustically distinct, according to Gee. For instance, most sonic booms have two shock waves, but the Falcon 9 booster produces a boom with three shocks as it descends through the atmosphere after launch. Gee co-authored a paper earlier this year analyzing the acoustic signatures of three Falcon 9 flyback sonic booms. While the first and third shocks were what one might typically expect, the second central shock "is formed by a combination of the grid fins and the lower portions of the booster, including the folded landing legs," Gee and BYU colleague Mark C. Anderson wrote. "These lower portions of the booster produce a rarefaction wave that tends to migrate toward the back of the shock system while the grid fins produce a shock wave that tends to migrate toward the front of the shock system." Those shock waves merge, and their relative strengths determine where this second shock appears in the full sonic boom acoustic signature. Sonic booms from rockets are also lower frequency, with peaks of less than 1 Hz—below the range of human hearing. The result is less of a "boom" and more of a "bang," according to Gee, that can last a few seconds, compared to milliseconds for a typical acoustic wave. It's more akin to a seismic wave, particularly if one is indoors when it hits. "Sometimes you get a very low amplitude rumble, but it comes on suddenly, and it's there for a few seconds and disappears," he said. It's also one reason why the sonic booms can travel so far afield of the Vandenberg base. Could the similarities confuse California residents who might mistake a sonic boom for an earthquake? Perhaps, at least until residents learn otherwise. "Since we're often setting up in people's backyard, they text us the results of what they heard," said Gee. "It's fantastic citizen science. They'll tell us the difference is that the walls shake but the floors don't. They're starting to be able to tell the difference between an earthquake or a sonic boom from a launch." Launch trajectories of Falcon 9 rockets along the California coast. Credit: Kent Gee A rocket's trajectory also plays an important role. "Everyone sees the same thing, but what you hear depends on where you're at and the rocket's path or trajectory," said Gee, adding that even the same flight path can nonetheless produce markedly different noise levels. "There's a focal region in Ventura, Oxnard, and Camarillo where the booms are more impactful," he said. "Where that focus occurs changes from launch to launch, even for the same trajectory." That points to meteorology also being a factor: Certain times of year could potentially have more impact than others as weather conditions shift, with wind shears, temperature gradients, and topography, for instance, potentially affecting the propagation of sonic booms. In short, "If you can change your trajectory even a little under the right meteorological conditions, you can have a big impact on the sonic booms in this region of the country," said Gee. And it's only the beginning of the project; the team is still gathering data. "No two launches look the same right now," said Gee. "It's like trying to catch lightning." As our understanding improves, he sees the conversation shifting to more subjective social questions, possibly leading to the development of science-based local regulations, such as noise ordinances, to address any negative launch impacts. The next step is to model sonic booms under different weather conditions, which will be challenging due to coastal California's microclimates. "If you've ever driven along the California coast, the weather changes dramatically," said Gee. "You go from complete fog at Vandenberg to complete sun in Ventura County just 60 miles from the base." Jennifer Ouellette Senior Writer Jennifer Ouellette Senior Writer Jennifer is a senior writer at Ars Technica with a particular focus on where science meets culture, covering everything from physics and related interdisciplinary topics to her favorite films and TV series. Jennifer lives in Baltimore with her spouse, physicist Sean M. Carroll, and their two cats, Ariel and Caliban. 1 Comments