It’s possible that I shall make an ass of myself. But in that case one can always get out of it with a little dialectic. I have, of course, so worded my proposition as to be right either way (K.Marx, Letter to F.Engels on the Indian Mutiny)
Wednesday, July 10, 2024
SPACE
Stars hint at an unusual black hole lurking in our Galaxy
Images taken by the Hubble Space Telescope point to an elusive
intermediate-size black hole in the star cluster ω Centauri.
Astronomers can use the movements of stars to determine the location of a black hole (illustration).Credit: Victor de Schwanberg/Science Photo Library
By perusing two decades’ worth of pictures from the Hubble Space Telescope archives, astrophysicists have found what could be evidence of a nearby black hole at least 8,200 times as massive as the Sun.
The object would be the second-largest black hole to be found in our Galaxy, if further studies can confirm the findings, which are described today in Nature1. It could also be the strongest candidate yet for an intermediate-mass black hole — an object in the enigmatic no-man’s land between the ‘super massive’ black holes thought to lie at the centre of most galaxies, and much smaller ones that weigh about as much as a single large star.
Fast-moving stars
Astrophysicist Maximilian Häberle at the Max Planck Institute for Astronomy in Heidelberg, Germany, and his collaborators examined more than 500 images of ω Centauri, a dense cluster of 10 million stars around 18,000 light years (5.43 kiloparsec) from the Solar System. The images were mostly taken to help calibrate Hubble’s instruments over the years.
The team patched the images together to reconstruct the movement of more than 150,000 stars in the cluster. Most stars moved in the way that theoretical models predict, Häberle says. “But then, there were some that were moving faster.” Seven stars, all close to the centre of ω Centauri, were moving too fast to be held by the gravity of the cluster alone.
This suggested that the stars had been accelerated by the gravitational pull of a massive object, such as a black hole. From the stars’ velocities, it would need to be at least 8,200 solar masses, but it could weigh as much as 50,000 suns. “We did not know before whether we would find it or not,” says Häberle. “It was a little bit of a risk, and we might have found nothing.”
Images taken by the Hubble Space Telescope suggest that an intermediate-size black hole could be lurking in the star cluster ω Centauri.Credit: ESA/Hubble & NASA, M. Häberle (MPIA)
“It’s a hard experiment,” and the evidence for the presence of a black hole is “very far from conclusive”, says Gerry Gilmore, an astrophysicist at the University of Cambridge, UK. In particular, the data show no evidence yet of the trajectories curving, as one would expect from stars orbiting a massive object. In the case of Sagittarius A*, the black hole of 4.3 million solar masses at the centre of the Milky Way, years of observations found incontrovertible proof of such curved orbits — for which two of the lead researchers won a Nobel Prize in 2020. The Gaia space telescope has also spotted some dormant, star-sized black holes, from the motion of a single companion star2.
Most black holes have been found over the past half century by detecting radiation such as X-rays or radio waves3 produced by superheated gas that’s spiralling into the hole; the first hint of the presence of Sagittarius A* was indeed a radio source — albeit not a very bright one. But no such emissions have been found in ω Centauri.
Mysterious middleweights
The mass of the candidate object in ω Centauri would put it squarely in the intermediate-mass black hole range, generally considered to span between around 100 and 100,000 solar masses. So far, the only solid evidence for black holes in this range comes from detecting gravitational waves produced by two merging black holes. One such event, seen in 2019, is thought to have produced an object of around 150 solar masses.
The search for midsize black holes has a long history of claims that are later disproven. Astrophysicists long suspected that some sources of ‘ultraluminous’ X-rays could be black holes in this size range. But most of those candidates have now been shown to be neutron stars that shine unusually bright by overheating matter from a companion star. “These are most likely associated with 'normal' young binary systems,” says Giuseppina Fabbiano, an astrophysicist at the Harvard–Smithsonian Center for Astrophysics in Cambridge, Massachusetts.
Big questions remain — including how some black holes come to be super massive, and whether they are the result of multiple mergers, starting from stellar-mass black holes and going through intermediate masses such as that of the ω Centauri candidate.
Astronomers find nearest massive black hole – study
A new colored Esa/Hubble image of Omega Centauri (Esa/Hubble and Nasa/M Haberle [MPIA]/PA)
By Nina Massey, PA Science Correspondent
Fast-moving stars seen in a nearby star cluster within the Milky Way suggest the presence of an elusive black hole which may be the closest one to Earth, researchers say.
The star cluster, Omega Centauri, is a collection of around 10 million stars, visible as a smudge in the night sky south of the Equator.
It looks no different to similar clusters through a small telescope, but the new study confirms what astronomers had been suspecting for some time – it contains a central black hole.
At a distance of about 18,000 light-years, this is the closest known example of a massive black hole
Dr Nadine Neumayer
The black hole, which is at a distance of about 18,000 light-years, appears to be stuck in an intermediate stage of evolution, and is considerably less massive than typical black holes in the centres of galaxies.
Researchers say the finding appears to be the missing link between stellar and supermassive black holes.
Black holes have been observed in various sizes, including stellar-mass black holes with masses around five to 150 times that of the Sun, to supermassive black holes which are more than 100,000 times the mass of the Sun.
However, only a few intermediate-mass black holes, between 150 and 100,000 times the mass of the Sun, have been discovered.
Omega Centauri seems to be the core of a small, separate galaxy whose evolution was cut short when the Milky Way swallowed it, the study suggests.
Dr Nadine Neumayer, a group leader at the Max Planck Institute for Astronomy in Germany, said: “Previous studies had prompted critical questions of ‘So where are the high-speed stars?’
“We now have an answer to that and the confirmation that Omega Centauri contains an intermediate-mass black hole.
“At a distance of about 18,000 light-years, this is the closest known example of a massive black hole.”
The supermassive black hole in the centre of the Milky Way is at a distance of about 27,000 light-years.
The study, led by Maximilian Haberle of the Max Planck Institute for Astronomy, is based on more than 20 years of Hubble Space Telescope observations, and published in the Nature journal.
Writing in an accompanying article, Daryl Haggard and Adrienne Cool said: “These newly discovered stars offer the best evidence yet that Alpha Centauri harbours an intermediate-mass black hole.”
The results could suggest that searching for intermediate-mass black holes in other globular clusters may be warranted.
To guard against cyberattacks in space, researchers ask ‘what if?’
The Conversation July 9, 2024 Complex space systems like the International Space Station could be vulnerable to hackers.
If space systems such as GPS were hacked and knocked offline, much of the world would instantly be returned to the communications and navigation technologies of the 1950s. Yet space cybersecurity is largely invisible to the public at a time of heightened geopolitical tensions.
Cyberattacks on satellites have occurred since the 1980s, but the global wake-up alarm went off only a couple of years ago. An hour before Russia’s invasion of Ukraine on Feb. 24, 2022, its government operatives hacked Viasat’s satellite-internet services to cut off communications and create confusion in Ukraine.
Most people are unaware of the crucial role that space systems play in their daily lives, never mind military conflicts. For instance, GPS uses signals from satellites. GPS-enabled precision timing is essential in financial services where every detail – such as time of payment or withdrawal – needs to be faithfully captured and coordinated. Even making a mobile phone call relies on precise coordination of time in the network.
Besides navigation for airplanes, boats, cars and people, GPS is also important for coordinating fleets of trucks that transport goods to stock local stores every day.
Earth-observation satellites are “eyes in the skies” with a unique vantage point to help forecast the weather, monitor environmental changes, track and respond to natural disasters, boost agricultural crop yields, manage land and water use, monitor troop movements and much more. The loss of these and other space services could be fatal to people vulnerable to natural disasters and crop failure. They could also put global economics and security at serious risk.
Many satellites are crucial for tracking natural and human activity here on Earth. NASA
Factors in play
In our report, we identified several factors that contribute to the increasing threat of space cyberattacks. For instance, it’s important to recognize that the world is at the start of a new space race.
Because space is so remote and hard to access, if someone wanted to attack a space system, they would likely need to do it through a cyberattack. Space systems are particularly attractive targets because their hardware cannot be easily upgraded once launched, and this insecurity worsens over time. As complex systems, they can have long supply chains, and more links in the chain increase the chance of vulnerabilities. Major space projects are also challenged to keep up with best practices over the decade or more needed to build them.
And the stakes are unusually high in space. Orbital trash zips around at speeds of 6 to 9 miles per second and can easily destroy a spacecraft on impact. It can also end space programs worldwide given the hypothesized Kessler syndrome in which the Earth is eventually imprisoned in a cocoon of debris. These consequences weigh in favor of space cyberattacks over physical attacks because the debris problem is also likely to affect the attacker.
Moreover, given critical space infrastructure and services, such as GPS, conflicts in space can spark or add more fuel to a conflict on Earth, even those in cyberspace. For instance, Russia warned in 2022 that hacking one of its satellites would be taken as a declaration of war, which was a dramatic escalation from previous norms around warfare. Conjuring scenarios
Even security professionals who recognize the severity of this space cybersecurity threat face a major challenge. At least in nonclassified forums, only a couple of under-specified scenarios are typically considered: something vague about satellite hacking and something vague about signals jamming or spoofing.
But failure to imagine a full range of possibilities can be devastating for security planning, especially against hackers who are a diverse set of entities with diverse motivations and targets. These variables are vital to nail down because they reveal clues about which strategies and levers defenders may find most effective in a response. For instance, an attack by a state-sponsored hacker may require a different approach than, say, one by a criminal hacker after money or by a chaos agent.
To help with this piece of the security puzzle, our report offers a taxonomy – the ICARUS matrix – that captures these variables and can create more than 4 million unique combinations of variables, which we call scenario prompts. ICARUS is an acronym for “imagining cyberattacks to anticipate risks unique to space.”
Here are three of the 42 scenarios we included in the report.
A 3D or additive printer can be an invaluable resource for quickly creating parts on demand on space missions. A hacker could gain access to a printer on a space station and reprogram it to make tiny imperfections inside the parts it prints. Some of these built-to-fail components could be parts of critical systems.
A hacked 3D printer could be used to introduce faulty parts to a space station.
A hacker could corrupt the data from a planetary probe to show inaccurate atmospheric, temperature or water readings. Corrupted data from a Mars rover, for example, could falsely show that an area has significant subsurface water ice. Any subsequent mission launched to explore the site further would be wasted.
In 1938, a radio drama about an alien attack instigated a panic when many listeners didn’t realize it was fictional. Similarly, a hacker could access the listening feeds of the Messaging Extraterrestrial Intelligence, or METI, project and insert something resembling alien language in METI’s transcription. They could then leak it to the media, potentially creating panic worldwide and moving financial markets.
Other scenarios in our report involve such things as insider threats, AI vulnerabilities, false flag attacks, ecoterrorism, ransomware during a launch, as well as more distant scenarios about asteroid mining, off-world colonies and space pirates. Stories for better security
People are hardwired to respond to stories, whether shared around prehistoric campfires or across digital platforms today. Thus, crafting novel and surprising scenarios can help bring to life the invisible threat of space cyberattacks, as well as spotlight nuances across different scenarios that may require interdisciplinary experts to tackle together. Patrick Lin, Professor of Philosophy, California Polytechnic State University
A four-year delay, was followed on launch day by a one-hour delay, but the Ariane 6 rocket has finally made it to space. The European vessel is carrying a payload of small satellites.
The European Space Agency (ESA) sent its Ariane 6 rocket into space for the first time on Tuesday, some four years after its initial planned launch.
The powerful rocket lifted off from Europe's spaceport in Kourou, French Guiana at 4 p.m. local time (1900 GMT). The successful launch paves the way for Europe to get satellites into space without having to rely on other organizations or companies such as SpaceX.
ESA chief Josef Aschbacher said the successful launch marked a "historic day" for Europe.
"Ariane 6 demonstrated a successful liftoff, launch to orbit and deployment of satellites," the ESA wrote on X, formerly Twitter.
"We have now entered into a new era of spaceflight for Europe, powering us into space and allowing us to realize our ambitions onthe world stage," it wrote
Ariane 6 replaces its predecessor, Ariane 5, which first took off in the mid-90s.
The last Ariane 5 flight was last year, since then the ESA had to rely on rivals in order to get its satellites into space.
The launch was delayed by an hour, after having to wait four years, due to a fault being discovered in the morning.
Its success was far from guaranteed, with around half of all inaugural flights ending in failure, including that of the Ariane 5 in 1996. Commercial flights planned by end of year
The next stage for the ESA will be to study the launch before rolling out a commercial program.
Some 29 missions are already on the books for flights expected to start by the end of the year. Many are to deploy some of Amazon's Kuiper constellation of internet satellites.
Space flights have become a big business, with SpaceX's reusable Falcon rockets now taking off around twice a week.
The ESA will also be looking to "successfully ramp up" the number of flights, the agency's space transportation director Toni Tolker-Nielsen said.
Ariane 6 is set to launch on July 9. Many have complained that it took far longer for Europe to develop its new rocket than expected. DW explains why it took 10 years.
ESA's flagship heavy-lift rocket, Ariane 6, was develop and tested around Europe
Frank T. Koch/ArianeGroup/dpa/picture alliance
A week may be a long time in politics — for some, a day is quite enough — but in rocket science, not even a single year would get you past the first post.
It took Ariane 6, Europe's flagship heavy-lift rocket, two full years just to get a green light to be developed. And it took another eight years being built before its inaugural flight, which is scheduled for July 9, 2024 from French Guiana.
Building a whole new rocket system takes more than just creating a new rocket that shoots satellites into space.
A rocket system not only includes the rocket, often in various constellations, but also its engines, the fuel — which in Ariane 6's case is a new concoction of liquid oxygen and liquid hydrogen — a dedicated launchpad and a manufacturing network to create it all.
Throw a global pandemic into the mix and 10 years is nothing. Here's how Ariane 6's decade in development evolved. Ariane 6 timeline: 2014-2016
It all started in 2014, with a proposal from European industry: They said they wanted to completely change the way rockets were designed, developed, produced and launched.
The plan was, and still is, for Ariane 6 to be the main workhorse for Europe's space industry, launching European satellites into space on European-built rockets.
The European Space Agency (ESA) took the proposal to its 22 member states. Each had to sign off on the idea.
But the engineers were already hard at work designing the system.
"You need to have your concepts ready. You lay out your production system, how you want to manufacture and assemble your rocket," said ESA's Tina Büchner da Costa, an Ariane 6 launch system architect based at Europe's spaceport in Kourou, French Guiana.
The Ariane 6 rocket will launch from Europe's spaceport in Kourou, French Guiana, like the previous version, Ariane 5 (seen here in 2019)Image: Patrick Aventurier/abaca/picture alliance
"We had to demonstrate that we could double the launch rate [compared to the rocket's predecessor, Ariane 5], and at the same time reduce the cost," said Büchner da Costa.
In 2015, the first contracts were drawn up: The ArianeGroup, an aerospace company based in France, would produce the rocket, and the French space agency, CNES, got the launchpad.
And in 2016, they got the green light.
Ariane 6 timeline: 2017-2019
In 2017, the ArianeGroup began developing its manufacturing chain and producing the first elements of what's called a Flight Model 1 (FM1) version of the rocket.
During 2018 and 2019, four engines were tested and qualified. First, the Vulcain 2.1 engine, which powers the lower stage of the rocket. Then, the Vinci engine in the upper stage of the rocket — the Vinci engine can reignite in space, allowing Ariane 6 to release satellites at different locations on a single mission.
There was also a solid booster P120 engine, and, finally, a new, auxiliary propulsion unit (APU) — all had to be built, tested and verified, step by step.
"On every engine, you have several valves and other components that have to be tested at their own level before you can integrate them into an engine," said Büchner da Costa. "Once you go to full engine testing, that's a huge system that you need to test on a dedicated bench."
A brand new test bench was built at a German Space Agency site at Lampoldshausen to test the entire upper stage of Ariane 6.
Big hole: In 2017, DW Science Editor Zulfikar Abbany was in French Guiana for a Vega rocket launch and saw early construction work on the Ariane 6 launch site
Zulfikar Abbany/DW
Meanwhile, in French Guiana, CNES had been digging a massive hole in the ground where eventually they would build the Ariane 6 launch site.
"It all happens in parallel. You start with the smallest products and keep integrating them into a system that becomes more and more complex," said Büchner da Costa.
Ariane 6 timeline: 2020-2022
During the pandemic years, even Ariane 6 took a hit. COVID-19 had an "immense impact" on construction at the launch site in Kourou, said Büchner da Costa.
"There were 700 people working here and within a few days, they got reduced to 50. The supply in materials slowed, logistics broke down, production in Europe slowed significantly," she said. "You don't feel it at the paper stage, but you do feel it in production."
By 2021, however, they had started moving bits of the rocket from Europe to French Guiana and conducted "early combined tests."
They tested a mock-up of the central core of the rocket, the cranes that move it to the launchpad and the cryogenic arms that fuel and cool the rocket at launch.
And — almost as a side note — they also custom-built the ship they used to transport launcher components so it was more climate-friendly: the "Canopee" sailing cargo ship uses a hybrid propulsion system, partially powered by wind. Ariane 6 timeline: 2023-2024
Things started to pick up again in 2023. "We spent the whole of 2023 marrying the launchpad with the rocket," said Büchner da Costa.
The main stage was tested in French Guiana. "We fired up the main engine and tested the full flight up to [the rocket's initial] separation," said Büchner da Costa. That's over 7 minutes of flight.
The next part of the flight, where the upper stage goes in orbit, was qualified at the new test bench in Germany, "completely separately."
At the same time, engineers in Switzerland tested the fairing — that's the bit that carries the cargo and, perhaps one day, a capsule for human spaceflight — and the separation of the fairing.
"You test your system, step by step, in an incremental way, before you add any critical elements," said Büchner da Costa.
They did five complete countdowns and Büchner da Costa was there for them all. "It was really impressive to see, a full success," she said.
A full success up to 2024: the year of Ariane 6's first full mission with cargo, including cubeSats satellites and scientific experiments.
At time of writing in late June 2024, six launches were planned for 2025 and eight for 2026. By 2027, the ESA aims to achieve a launch rate of 10 per year — and then keep evolving.
Ariane 6 is about versatility, said Büchner da Costa, calling the rocket an "eierlegende Wollmilchsau." That's a German term for which there is no direct translation, but basically means something that can do a bit of everything.
"The 'eierlegende Wollmilchsau' is a pig that gives you milk, wool and lays eggs," explained Büchner da Costa. "That's what we want from Ariane 6. The exciting thing is that [Ariane 6] gives us versatility. We want to fly anywhere."
This article was original published on June 28, 2024. It has been updated with the date of Ariane 6's scheduled launch.
Edited by: Fred Schwaller Zulfikar Abbany Senior editor fascinated by space, AI and the mind, and how science touches people
SpaceX launches Falcon 9 rocket with first satellite built entirely in Turkey
A SpaceX Falcon 9 rocket launches the Turksat 6 communications satellite for Turkey from Launch Complex 40 at the Cape Canaveral Space Force Station in Florida on Monday. Photo by Joe Marino/UPI | License Photo
July 8 (UPI) -- After a two-hour weather delay, SpaceX launched from Cape Canaveral Space Force Station on Monday night a Falcon 9 rocket carrying aloft Turkey's first home-grown communications satellite.
The rockets lifted off at 7:30 p.m., the 50th by the private company this year from Florida.
Eight minutes later, the booster landed on the SpaceX droneship Just Read the Instruction in the Atlantic Ocean.
The Turksat 6A satellite was later released to its temporary orbit about 70 minutes after liftoff.
"All systems are looking good for today's launch of the @Turksat 6A mission from Florida. Weather conditions have improved for liftoff, and propellant load is underway," SpaceX posted on X about the showers.
It also was hot there. At 3:55 p.m., the heat index was 108 degrees at Cape Canaveral Space Force Station, the National Weather Service reported.
The four-hour launch window started at 5:21 p.m.
Turkey has had satellites launched before but this is the first one to be entirely built in the Middle East nation. Turkey is just the 11th country capable of manufacturing its own communications satellites.
In December 2021, SpaceX launched the Turksat 5B communications satellite to geostationary orbit 22,236 miles above Earth. It joined Turksat 5A, which flew in January 2021 during the Cape's first rocket launch of that year.
The Falcon 9 first stage launched for a 15th time.
It was part of SpaceX's 26th Commercial Resupply Services mission to the International Space Station on Nov. 9. It has also sent into orbit the 16th batch of OneWeb satellites and eight Starlink flights.
"Our local and national communication satellite, which will have a power of 7.5 kilowatts, will have 20 transponders," Abdulkadir Uraloglu, Turkey's Minister of Transport and Infrastructure, said in a September 2023 news release. "Our TURKSAT 6A satellite will serve in Ku Band and will also provide service in new geography such as South-East Asia, which could not be covered by previous Turksat satellites."
The satellite will provide data relay for civil and military communications to the Anatolian peninsula as well as most of the European continent, the Middle East and the westernmost part of the Russian federation, the Kennedy Space Center Visitor Complex reported.
The 9,400-pound satellite is designed to have a 15-year lifespan and will increase the reach of Turkey's satellites "from 3.5 billion to 5 billion" people, Uraloglu said.
‘Ready to come out?’ Scientists reemerge after year ‘on Mars’ Agence France-Presse July 7, 2024 (AFP)
The NASA astronaut knocks loudly three times on a what appears to be a nondescript door, and calls cheerfully: “You ready to come out?”
The reply is inaudible, but beneath his mask he appears to be grinning as he yanks the door open — and four scientists who have spent a year away from all other human contact, simulating a mission to Mars, spill out to cheers and applause.
Anca Selariu, Ross Brockwell, Nathan Jones and team leader Kelly Haston have spent the past 378 days sealed inside the “Martian” habitat in Houston, Texas, part of NASA’s research into what it will take to put humans on the Red Planet.
They have been growing vegetables, conducting “Marswalks,” and operating under what NASA terms “additional stressors” — such as communication delays with “Earth”, including their families; isolation and confinement.
It’s the kind of experience that would make anyone who lived through pandemic lockdowns shudder — but all four were beaming as they reemerged Saturday, their hair slightly more unruly and their emotion apparent.
“Hello. It’s actually so wonderful just to be able to say hello to you,” Haston, a biologist, said with a laugh.
“I really hope I don’t cry standing up here in front of all of you,” Jones, an emergency room doctor, said as he took to the microphone — and nearly doing just that several moments later as he spotted his wife in the crowd.
The habitat, dubbed Mars Dune Alpha, is a 3D printed 1,700 square-foot (160 square-meter) facility, complete with bedrooms, a gym, common areas, and a vertical farm to grow food.
An outdoor area, separated by an airlock, is filled with red sand and is where the team donned suits to conduct their “Marswalks”, though it is still covered rather than being open air.
“They have spent more than a year in this habitat conducting crucial science, most of it nutrition-based and how that impacts their performace … as we prepare to send people on to the Red Planet,” Steve Koerner, deputy director at NASA’s Johnson Space Center, told the crowd.
“I’m very appreciative.”
This mission is the first of a series of three planned by NASA, grouped under the title CHAPEA — Crew Health and Performance Exploration Analog.
A year-long mission simulating life on Mars took place in 2015-2016 in a habitat in Hawaii, and although NASA participated in it, it was not at the helm.
Under its Artemis program, America plans to send humans back to the Moon in order to learn how to live there long-term to help prepare a trip to Mars, sometime towards the end of the 2030s.
Even short trips to space can change an astronaut’s biology
The Conversation July 5, 2024 A SpaceX Crew Dragon named Endeavour is carrying four astronauts to the International Space Station (AFP)
Only about 600 people have ever traveled to space. The vast majority of astronauts over the past six decades have been middle-aged men on short-duration missions of fewer than 20 days.
Today, with private, commercial and multinational spaceflight providers and flyers entering the market, we are witnessing a new era of human spaceflight. Missions have ranged from minutes, hours and days to months.
As humanity looks ahead to returning to the Moon over the coming decade, space exploration missions will be much longer, with many more space travelers and even space tourists. This also means that a wider diversity of people will experience the extreme environment of space – more women and people of different ethnicities, ages and health status.
Since people respond differently to the unique stressors and exposures of space, researchers in space health, like me, seek to better understand the human health effects of spaceflight. With such information, we can figure out how to help astronauts stay healthy both while they’re in space and once they return to Earth.
As part of the historic NASA Twins Study, in 2019, my colleagues and I published groundbreaking research on how one year on board the International Space Station affects the human body.
These papers are part of the Space Omics and Medical Atlas package of manuscripts, data, protocols and repositories that represent the largest collection ever assembled for aerospace medicine and space biology. Over 100 institutions from 25 countries contributed to the coordinated release of a wide range of spaceflight data.
The NASA Twins Study
NASA’s Twins Study seized on a unique research opportunity.
NASA selected astronaut Scott Kelly for the agency’s first one-year mission, during which he spent a year on board the International Space Station from 2015 into 2016. Over the same time period, his identical twin brother, Mark Kelly, a former astronaut and current U.S. senator representing Arizona, remained on Earth.
NASA astronaut Scott Kelly, left, who went into space during the NASA Twins Study, stands next to his twin brother, Mark Kelly, who stayed on Earth. AP Photo/Pat Sullivan
My team and I examined blood samples collected from the twin in space and his genetically matched twin back on Earth before, during and after spaceflight. We found that Scott’s telomeres – the protective caps at the ends of chromosomes, much like the plastic tip that keeps a shoelace from fraying – lengthened, quite unexpectedly, during his year in space.
When Scott returned to Earth, however, his telomeres quickly shortened. Over the following months, his telomeres recovered but were still shorter after his journey than they had been before he went to space.
As you get older, your telomeres shorten because of a variety of factors, including stress. The length of your telomeres can serve as a biological indicator of your risk for developing age-related conditions such as dementia, cardiovascular disease and cancer.
In a separate study, my team studied a cohort of 10 astronauts on six-month missions on board the International Space Station. We also had a control group of age- and sex-matched participants who stayed on the ground.
We measured telomere length before, during and after spaceflight and again found that telomeres were longer during spaceflight and then shortened upon return to Earth. Overall, the astronauts had many more short telomeres after spaceflight than they had before.
One of the other Twins Study investigators, Christopher Mason, and I conducted another telomere study – this time with twin high-altitude mountain climbers – a somewhat similar extreme environment on Earth.
We found that while climbing Mount Everest, the climbers’ telomeres were longer, and after they descended, their telomeres shortened. Their twins who remained at low altitude didn’t experience the same changes in telomere length. These results indicate that it’s not the space station’s microgravity that led to the telomere length changes we observed in the astronauts – other culprits, such as increased radiation exposure, are more likely.
Civilians in space
In our latest study, we studied telomeres from the crew on board SpaceX’s 2021 Inspiration4 mission. This mission had the first all-civilian crew, whose ages spanned four decades. All of the crew members’ telomeres lengthened during the mission, and three of the four astronauts also exhibited telomere shortening once they were back on Earth.
The crew members from SpaceX’s 2021 Inspiration4 mission. SpaceX, CC BY-NC
What’s particularly interesting about these findings is that the Inspiration4 mission lasted only three days. So, not only do scientists now have consistent and reproducible data on telomeres’ response to spaceflight, but we also know it happens quickly. These results suggest that even short trips, like a weekend getaway to space, will be associated with changes in telomere length.
Scientists still don’t totally understand the health impacts of such changes in telomere length. We’ll need more research to figure out how both long and short telomeres might affect an astronaut’s long-term health.
Telomeric RNA
In another paper, we showed that the Inspiration4 crew – as well as Scott Kelly and the high-altitude mountain climbers – exhibited increased levels of telomeric RNA, termed TERRA.
Telomeres consist of lots of repetitive DNA sequences. These are transcribed into TERRA, which contributes to telomere structure and helps them do their job.
Together with laboratory studies, these findings tell us that telomeres are being damaged during spaceflight. While there is still a lot we don’t know, we do know that telomeres are especially sensitive to oxidative stress. So, the chronic oxidative damage that astronauts experience when exposed to space radiation around the clock likely contributes to the telomeric responses we observe.
We also wrote a review article with a more futuristic perspective of how better understanding telomeres and aging might begin to inform the ability of humans to not only survive long-duration space travel but also to thrive and even colonize other planets. Doing so would require humans to reproduce in space and future generations to grow up in space. We don’t know if that’s even possible – yet. Plant telomeres in space
My colleagues and I contributed other work to the Space Omics and Medical Atlas package, as well, including a paper published in Nature Communications. The study team, led by Texas A&M biologist Dorothy Shippen and Ohio University biologist Sarah Wyatt, found that, unlike people, plants flown in space did not have longer telomeres during their time on board the International Space Station.
The plants did, however, ramp up their production of telomerase, the enzyme that helps maintain telomere length.
As anyone who’s seen “The Martian” knows, plants will play an essential role in long-term human survival in space. This finding suggests that plants are perhaps more naturally suited to withstand the stressors of space than humans.
![A new colored Esa/Hubble image of Omega Centauri (Esa/Hubble and Nasa/M Haberle [MPIA]/PA)](https://focus.belfasttelegraph.co.uk/thumbor/AET3DTWG5MUgRuoQxhyvsiip5Gg=/0x0:0x0/960x640/prod-mh-ireland/0efece6b-8563-4946-aee8-8d5d8e57a2b5/e78c1785-2f61-4c0f-95bc-1ad1cf51e501/a2ffdfff-6560-480d-812c-d9ec3f2f82da.png)
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