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Yahoo
a day ago
- Science
- Yahoo
How many satellites could fit in Earth orbit? And how many do we really need?
When you buy through links on our articles, Future and its syndication partners may earn a commission. In the last five years, the number of satellites orbiting Earth has more than doubled and will likely double again within a similar timespan, thanks to the efforts of private companies such as SpaceX. But while these spacecraft can provide important benefits, they are also causing multiple issues that are only just being realized by scientists. So, how many satellites can we expect to see in our skies in the coming decades? And — more importantly — how many is too many? As of May 2025, there are around 11,700 active satellites in orbit around Earth, ranging from military spy satellites and scientific probes to rapidly growing private satellite networks. But the rate at which spacecraft are being launched into space is increasing year-on-year. The biggest contributor to this trend is SpaceX's Starlink constellation, which currently has around 7,500 active satellites in orbit — more than 60% of the total number of operational orbiting spacecraft, Jonathan McDowell, an astronomer at the Harvard & Smithsonian Center for Astrophysics who has been tracking satellites since 1989, told Live Science. All of these have been launched since May 2019. However, other organizations are also beginning to develop their own "megaconstellations," such as Amazon's Project Kuiper and China's "Thousand Sails" constellation. It is also getting easier to put new satellites into space thanks to the reusability of rockets, such as SpaceX's Falcon 9 rocket, which is being used to launch multiple competing satellite networks. Other companies are also exploring new ways of launching larger payloads, including shooting hundreds of satellites into space at once using a giant spinning cannon. Related: There was nearly 1 rocket launch attempt every 34 hours in 2024 — this year will be even busier All of this activity has left researchers wondering how many satellites could eventually end up orbiting our planet and what problems they might cause along the way. "Megaconstellations are planning to cover most of the Earth's surface," Fionagh Thomson, a senior research fellow at the University of Durham in the U.K. who specializes in space ethics, told Live Science. But there is still "a large amount of uncertainty" over how large they might get and how damaging they could become, she added. It is difficult to estimate how many satellites will be launched in the future because satellite companies often change their plans, Aaron Boley, an astronomer at The University of British Columbia in Canada who has extensively studied the potential effects of megaconstellations, told Live Science. "Companies update their plans as they develop their systems, and many proposed systems will never be launched. But many will," Boley said. Proposals for more than 1 million private satellites belonging to around 300 different megaconstellations have been submitted to the International Telecommunications Union, which regulates communications satellites, according to a 2023 study co-authored by Boley. However, some of these, including a proposed 337,000-satellite megaconstellation from Rwanda, are unlikely to come to fruition, the researchers noted. The proposed number seems massive, but most private satellites have short lifespans. For example, the average Starlink satellite spends around five years operational, after which it falls back to Earth and burns up upon reentry. So even if all 1 million proposed satellites are launched, they will not all be orbiting Earth at once. While it is tricky to predict how many satellites will be launched and when, researchers have estimated a maximum number of spacecraft that can coexist within low-Earth orbit (LEO) — the region of space up to 1,200 miles (2,000 kilometers) above Earth's surface, where a vast majority of private satellites operate. Above this upper limit, or carrying capacity, satellites would likely start constantly crashing into one another. McDowell and Boley, as well as other astronomers — including Federico Di Vruno at the transnational Square Kilometer Array (SKA) Observatory and Benjamin Winkel at the Max Planck Institute for Radio Astronomy in Germany — all believe that the carrying capacity for LEO is around 100,000 active satellites. Above this number, new satellites will likely only be launched to replace those that come to the end of their operational lives. It is unclear exactly when this carrying capacity will be reached. However, based on the current rate of increasing launches, several experts told Live Science that it could happen before 2050. Given the impending rise in satellite numbers, researchers are hard at work trying to figure out what problems they may cause. A major issue associated with megaconstellations is space junk, including rocket boosters and defunct satellites, that will litter LEO before eventually falling back to Earth. If space junk collides , it could create thousands of smaller pieces of debris that increase the risk of further collisions. If left unchecked, this domino effect could render LEO effectively unusable. Researchers call this problem the "Kessler syndrome" and are already warning that it should be tackled now, before it is too late. Megaconstellations also threaten to severely limit ground-based astronomy in two main ways: First, light reflecting off satellites can interfere with optical astronomy by photobombing telescopes as they pass overhead; Second, electromagnetic radiation that unintentionally leaks from communications satellites can interfere with radio astronomy by obscuring signals from distant objects, such as faraway galaxies. If the carrying capacity is reached, some experts fear that the level of radio interference could render some types of radio astronomy completely impossible. Related: Controversial paper claims satellite 'megaconstellations' like SpaceX's could weaken Earth's magnetic field and cause 'atmospheric stripping.' Should we be worried? Satellites can also impact the environment via greenhouse gases that are emitted during rocket launches, as well as through metal pollution that is accumulating in the upper atmosphere as defunct satellites and other space junk burn up upon reentry. Given all these potential impacts, most researchers are calling for companies to reduce the rate at which they launch satellites. "I don't think a full stop on satellite launches would work," Boley said. "However, slowing things down and delaying the placement of 100,000 satellites until we have better international rules would be prudent." While private satellites help monitor Earth and connect rural and disadvantaged communities to high-speed internet, many experts argue that these benefits do not outweigh the potential risks. Others are more skeptical and question whether the payloads being put into orbit will really do any good or if they are just a way for companies to make more money. "Do we really need another CubeSat in space that allows us to take selfies?" Thomson asked. "And in reality, does connecting remote communities [to the internet] help solve systemic issues of inequality, poverty and injustice?" RELATED STORIES —Chinese scientists call for plan to destroy Elon Musk's Starlink satellites —World's 1st wooden satellite arrives at ISS for key orbital test —Geomagnetic storm sends 40 SpaceX satellites plummeting to Earth Many benefits could also be achieved with fewer satellites. The proposed numbers are so high, mainly because there are so many different companies competing to provide the same services. "It would be better to cooperate more, in order to need fewer satellites," Winkel told Live Science. "But I find that highly unlikely given the current situation in the world."
Yahoo
24-05-2025
- Science
- Yahoo
China Is Building an AI-Powered Supercomputer Network in Space
China is launching a space-bound AI supercomputer — and the first batch of the satellites it's comprised of was just sent up. As the South China Morning Post reports, the so-called "Three-Body Computing Constellation" project launched the first 12 of its planned 2,800 satellites last week from the Jiuquan Satellite Launch Center in northwest China. The orbital supercomputer network will, when complete, allow for rapid in-orbit data processing rather than relying on terrestrial computing facilities to relay information to Earth and then back up to space. It also doesn't require the copious amounts of water ground-based computers need to stay cool. Each satellite, the SCMP notes, carries an eight-billion-parameter AI model that can process raw data in orbit. Paired with the satellites' massive computing power of one quintillion operations per second, the constellation is expected, when complete, to rival the world's most powerful terrestrial supercomputers. Launched from northwest China's Jiuquan Satellite Launch Center, each satellite carries, per a statement from the ADA Space startup that helped launch the constellation, unique scientific payloads that can do everything from detect gamma ray bursts to create "digital twins" of Earth terrain for emergency services and other industries. While the concept of orbital computing is nothing new, this project is, as Harvard astronomer Jonathan McDowell told SCMP, "the first substantial flight test" of the gambit. As McDowell pointed out, theoretical space cloud computing projects are "very fashionable" right now, with private companies like Axiom Space and Jeff Bezos' Blue Origin planning their own orbital computing satellites. Unlike terrestrial data centers, which, according to the International Energy Agency are on track to use as much energy as Japan by 2026, orbital data centers can "use solar power and radiate their heat to space, reducing the energy needs and carbon footprint," as McDowell told SCMP. With the launch of the first of its 2,800 satellites, China's orbital supercomputer puts the country ahead of the United States in the rival countries' space race, though there's no telling which will actually cross the finish line first. More on the space race: White House Announces It Can Now "Manipulate Time and Space"
Yahoo
23-05-2025
- Science
- Yahoo
Chinese Spacecraft Accused of Dumping Experimental Fuel in Streak Seen Across American Sky
Across the American West, a massive glowing streak appeared in the skies last weekend — and an experimental rocket fuel seems to have been its source. As Live Science reports, the spectacular light show was almost certainly the result of spent fuel from ZhuQue-2E, a rocket from the Chinese startup Landspace that used a methane-based fuel known "methalox" as its upper stage burned. Launched on May 17, the rocket took off from the Jiuquan Satellite Launch Center in northwest China. On the other side of the Pacific Ocean, a mega-bright streak was seen over at least seven American states — Colorado, Idaho, Missouri, Nebraska, New Mexico, Utah, and Washington — and skywatchers online began speculating about what could have caused it. Around that same time, the Space Weather blog noted that the radiant tails were likely from the Chinese rocket. Harvard astrophysicist Jonathan McDowell later confirmed, per his own measurements, that the source of the "unusual luminous cloud" seen out west was from a ZhuQue-2E "fuel dump at the upper stage." As footage from the incredible spectacle shows, the massively bright streak lit up the entire night sky, which in some areas was already illuminated by auroras from a geomagnetic storm that just so happened to have occurred at the same time. Soon after the rocket made it to space, skywatchers began posting amazing footage of the mega-bright glowing streak — and as SpaceWeather noted at the time, those radiant streaks also took place during an aurora, which was caused by a geomagnetic storm that happened at the time same time. In the so-called "Methane Race to Orbit," Landspace scored a massive goal for its home country back in 2023, when it became the first company to successfully launch a rocket — another ZhuQue-2E, and its second such attempt — using methalox. In subsequent years, the American companies United Launch Alliance and Blue Origin became the second and third to launch spacecraft into orbit using the methane-based fuel, which is lauded by experts as far cleaner than the standard RP-1 kerosene that produces carbon dioxide when burned. In a prior interview with SpaceNews, rocket propulsion expert Filippo Maggi explained that although methane is, like CO2, also a greenhouse gas, it burns cleaner than RP-1 — and provides more energy, too. "If you produce a good propulsion unit, the efficiency of that unit can be as high as 99.5 percent," Maggi told the site back in 2021. "That means that the residues of methane would be basically zero. You might have some carbon monoxide released instead of carbon dioxide. But that would be very little." More on China's space case: Mysterious Bacteria Not Found on Earth Are Growing on China's Space Station
Time of India
21-05-2025
- Science
- Time of India
What is the unusual light seen over US skies? Here's all the details
People across several US states saw a white, aurora-like streak in the sky. The light came from a Chinese rocket that released fuel before reentering Earth's atmosphere. Experts confirmed it was a controlled release related to a satellite launch . Unusual Light On Saturday, May 17, at 1:24 a.m. ET, a bright streak appeared in the night sky. The light lasted for around 10 minutes before fading. It was seen across several states including Colorado, Utah, Idaho, Missouri, Nebraska, Washington and New Mexico, a report said. Photos of the event spread across social media and science platforms. Play Video Pause Skip Backward Skip Forward Unmute Current Time 0:00 / Duration 0:00 Loaded : 0.00% 0:00 Stream Type LIVE Seek to live, currently behind live LIVE Remaining Time - 0:00 1x Playback Rate Chapters Chapters Descriptions descriptions off , selected Captions captions settings , opens captions settings dialog captions off , selected Audio Track default , selected Picture-in-Picture Fullscreen This is a modal window. Beginning of dialog window. Escape will cancel and close the window. Text Color White Black Red Green Blue Yellow Magenta Cyan Opacity Opaque Semi-Transparent Text Background Color Black White Red Green Blue Yellow Magenta Cyan Opacity Opaque Semi-Transparent Transparent Caption Area Background Color Black White Red Green Blue Yellow Magenta Cyan Opacity Transparent Semi-Transparent Opaque Font Size 50% 75% 100% 125% 150% 175% 200% 300% 400% Text Edge Style None Raised Depressed Uniform Drop shadow Font Family Proportional Sans-Serif Monospace Sans-Serif Proportional Serif Monospace Serif Casual Script Small Caps Reset restore all settings to the default values Done Close Modal Dialog End of dialog window. Also Read: Grey's Anatomy Season 21: When will it stream on Netflix? Here's streaming release date in US and where to watch Season 21 now by Taboola by Taboola Sponsored Links Sponsored Links Promoted Links Promoted Links You May Like '허리로 고생하시던 엄마가 '시원하다'는 말, 처음 하셨어요' pt 더 알아보기 Undo What Was it? The light came from the Zhuque-2E rocket. This rocket launched from Jiuquan Satellite Launch Center in northwest China at 12:12 a.m. ET, as per Space News. It carried six satellites with scientific tools into low-Earth orbit . After release, the rocket reentered Earth's atmosphere and burned up. Fuel Dump Created Frozen Crystal Trail Jonathan McDowell, an expert who tracks space activity, explained the light. He said the rocket dumped fuel at about 155 miles above Earth. The fuel froze into tiny crystals in space. These crystals reflected sunlight back to Earth, creating a visible streak in the night sky. Live Events Also Read: Nine Perfect Strangers Season 2: Release date, episode schedule and where to watch in US and UK Zhuque-2E Rocket The Zhuque-2E is a single-use rocket made by the Chinese company LandSpace . It is 160 feet tall and can carry 13,200 pounds into low-Earth orbit. Most rockets use hydrogen or kerosene-based fuel. But this rocket used a mix of liquid oxygen and liquid methane, also called methalox . This type of fuel burns cleaner than others. FAQs What caused the white streak in the sky? The streak came from frozen fuel dumped by a Chinese rocket. The fuel crystals reflected sunlight, making the streak visible over parts of the US. What is special about the Zhuque-2E rocket? It uses a mix of liquid oxygen and methane fuel. This combination is different from traditional rocket fuels like hydrogen or kerosene.
Ammon
21-05-2025
- Science
- Ammon
Mystery as bright beam of light streaks through the skies over the US
Ammon News - Stargazers across the US have been baffled by a mysterious beam of light streaking through the sky. Around midnight on Saturday, May 17, a glowing streak was visible above the US as far south as New Mexico. With the aurora active after a surprise geomagnetic storm, many people initially thought the streak was STEVE - a white-mauve light emitted by rivers of charged particles. However, astronomers have now revealed the true explanation for this bizarre phenomenon. According to Dr Jonathan McDowell, an astronomer who tracks objects in space, the light was caused by a rocket dumping fuel. Just an hour or so before the light became visible, Chinese startup LandSpace Technology launched a methane and oxygen-fuelled Zhuque-2E Y2 rocket. Dr McDowell says the most likely source of the light was this rocket's second stage, releasing its 'Methalox' rocket fuel at about 155 miles (250km) above the ground. Once released into space, the chemicals in the fuel react with plasma in the Earth's ionosphere to create an eerie whitish glow, just like the one seen above the US. As the glowing streak appeared in the sky, many astronomers' first thought was that they were witnessing a rare space weather phenomenon called STEVE. Over the night of May 17, the Earth was experiencing a moderate (G2 class) geomagnetic storm after being hit by material from a solar eruption. The enormous 'bird wing' eruption had originally been predicted to miss Earth, but the wave of material was wider than expected, and the planet was hit with a glancing blow. Although STEVE is not part of the aurora, it is also caused by space weather and appears like a glowing river of whitish-mauve light in the sky. In a post on X, photographer Tyler Schlitt captured the event, writing: 'Just saw STEVE with my friends here in Southern Kansas is 45 minutes north of Greensburg!' However, it soon became apparent that this was no natural phenomenon. Writing on X, Dr McDowell said: 'TLEs confirm the Zhuque-2 upper stage passed over the US Four Corners area at 0525 UTC May 17 and is the source of the unusual luminous cloud seen by many observers.' The Zhuque-2 rocket was launched by LandSpace Technology from the Dongfeng Commercial Space Innovation Test Area in northwest China at 04:21 UTC. Daily Mail
