NEWS

We’ve talked a bit about the importance of operating responsibly in space: for example, disposing of satellites so they don’t end up contributing to the space debris problem. Is there any way to legally enforce responsible operation, though? Does anyone own space and have the ability to impose regulations on it? In other words, are there laws in space? Who owns space? Nobody owns the moon, the stars or outer space in general. The 1967 Outer Space Treaty, which has been agreed to by over a hundred nations, specifically forbids any nation from laying claim to outer space: ‘Outer space, including the Moon and other celestial bodies, is not subject to national appropriation by claim of sovereignty, by means of use or occupation, or by any other means.’ We’ll look at this treaty in more detail shortly. Although some companies claim to sell plots of land on the moon, nobody owns the land to sell it. Some have tried to argue that, although nations are barred from owning the moon, that doesn’t necessarily prevent individuals or corporations from owning it. If you make it to the moon, though, you’re unlikely to find that your moon deed is legally recognised. To look at it from a different perspective, everyone owns the moon. The Outer Space Treaty declares the exploration and use of outer space the ‘province of all mankind’, so nobody has the right to take private possession of part of the moon, thus excluding everyone else. The 1967 Outer Space Treaty As no one nation owns outer space, no nation can impose its laws on it. Because of this, the rules that govern space are formed by agreement between nations, which is why treaties are crucial for space law. The Treaty on Principles Governing the Activities of States in the Exploration and Use of Outer Space, including the Moon and Other Celestial Bodies, more concisely known as the Outer Space Treaty, first came into effect on 10 October 1967. This treaty laid the foundations of the laws of space. Royal Museums Greenwich offers a comparison to bring home how sparsely regulated space is, in comparison to Earth-based concerns: [The Outer Space Treaty] is just 17 short articles in length. By comparison, the International Law of the Sea Treaty – the set of rules governing the use of the world’s oceans – contains over 300 articles. Articles 13 to 17 of the Outer Space Treaty are about the treaty itself, so the first 12 articles are the important ones if you want to know the rules of space. Here’s a quick summary of those articles. Space is open to all. Outer space should be explored and used for the benefit of everyone. As mentioned, the exploration and use of space is the ‘province of all mankind’, and all states should have equal freedom to participate. Nobody owns space. No nation can lay claim to outer space or any celestial bodies. International law governs in space. States should carry out their exploration and use of outer space in accordance with international law: abiding by treaties, for example. Space is a peaceful place. Celestial bodies, such as the moon, can only be used for peaceful purposes. States are forbidden from installing weapons of mass destruction in space, and cannot test weapons or establish military bases on celestial bodies. Astronauts should be protected. States are to aid astronauts in distress, and to alert other states if they discover anything in space that could endanger astronauts. The 1968 Rescue Agreement would expand on this. Nations are responsible for their actions in space. Whether space-based actions are carried out by the government or by private organisations, that government or organisation’s state is responsible for making sure those actions comply with the Outer Space Treaty. Anything you launch is your responsibility. States are liable for damages caused to other states by anything they launch into space. The 1972 Liability Convention would expand on this. Anything you launch is your property. States retain the ownership of anything they launch into space. In other words, although nobody can own outer space, that doesn’t mean you’ll cease to own something you put into outer space. Respect your neighbours and the environment. States should bear the interests of other states in mind while exploring or making use of outer space. They should avoid ‘harmful contamination’ of celestial bodies or of the Earth in the process of their space exploration. Your neighbours should be able to monitor what you launch into space. States can request to observe the flight of objects launched by other states. Be clear about what you’re doing in space. Wherever feasible, states should inform the public, the scientific community and the Secretary-General of the United Nations about their actions in space. Welcome your neighbours to your space stations. States can request to visit other states’ space stations or their installations on celestial bodies. Other space treaties The use of space is largely governed by four international treaties. The Outer Space Treaty of 1967 is the most significant one, but we’ll take a quick look here at the other three: The 1968 Agreement on the Rescue of Astronauts, the Return of Astronauts and the Return of Objects Launched into Outer Space, also known as the Rescue Agreement. Under the terms of this agreement, states agree to help astronauts in distress in any way they can, and (if requested) to return objects that land in their territory after being launched into space by another state. The 1972 Convention on International Liability for Damage Caused by Space Objects, also known as the Liability Convention. This expands on the idea that states are responsible for damages caused by anything they launch into space. The 1975 Convention on Registration of Objects Launched into Outer Space, also known as the Registration Convention. This requires states to register the details of anything they launch into space with the United Nations. In theory, there’s a fifth treaty: the 1979 Agreement Governing the Activities of States on the Moon and Other Celestial Bodies, also known as the Moon Agreement, which attempts to set out rules for the use of the moon and its resources. As most spacefaring nations haven’t ratified the Moon Agreement, though, it doesn’t have the same impact on space law as its more widely accepted predecessors. The gaps in space law At the moment, space is sparsely and vaguely regulated. There are some points on which it could be worth clarifying the rules. For example, you may have noticed that none of these treaties specifically set out rules for satellite disposal, which is important for keeping space debris under control. There are a couple of ways in which existing space law might help to mitigate space debris, but there’s no article that forbids unnecessarily allowing space debris to be created. The Liability Convention, which holds states liable for damages caused by their own satellites, creates an incentive for governments to order that satellites must be disposed of responsibly. After all, if a state creates space debris by neglecting or destroying a satellite, they will then need to pay for any damage that the debris inflicts on other satellites. However, there’s still a chance a state might act recklessly, in spite of the risk that they might have to pay damages. Article 9 of the Outer Space Treaty, meanwhile, dictates that states should act with due regard to other states’ interests. Unnecessarily creating space debris could be considered a violation of this article, as space debris makes the use of space more difficult for everyone. However, the lack of specificity here means that different states may interpret this article differently. For example, after Russia destroyed one of its own satellites in a missile test in November 2021, creating a large amount of space debris, Russia’s foreign ministry claimed that the test had been carried out ‘in strict conformity with international law, including the 1967 Outer Space Treaty’. In 2008, the European Union attempted to create a code of conduct for outer space, which required countries to limit any activities that might create space debris. However, the International Code of Conduct for Outer Space Activities was never adopted. Perhaps it’s time for another treaty: one that explicitly forbids unnecessarily destroying a satellite in orbit, or launching a satellite without a responsible disposal plan in place. Something else you may have noticed is the fact that these treaties don’t address crime by individuals. In a future article, we’ll take a closer look at what happens when an astronaut commits a crime in space. Darwin Innovation Group is a UK-based company that provides services related to autonomous vehicles and communications. If you’re interested in working with us, take a look at our careers page. If you’d like to know how we can help your organisation make use of autonomous vehicles, contact us. You can also follow us on LinkedIn or Twitter.

Space is a dangerous place, so you need to be prepared before you go there. In particular, you’ll need to be ready for an environment where you can’t rely on your own weight, especially if you’re likely to leave your vessel at any point. On Earth, you’ll never experience the problem of getting trapped in mid-air in a room, because gravity means you’ll always be able to reach the floor. In space, though, if you’re not already moving and you can’t reach anything to pull on or push off, you can’t get anywhere. It’s not easy to practise being weightless on Earth, though, so how are you supposed to get that experience? In this post, we take a look at microgravity and how astronauts prepare for it. Why do astronauts float on the International Space Station? The further you move from Earth, the weaker Earth’s gravity becomes. However, the International Space Station (ISS) is relatively close to Earth. The ISS is in low Earth orbit, around 400 km above Earth’s surface. At this altitude, the force of Earth’s gravity is roughly 90% of the force on the planet’s surface. This means that, if you were 400 km above the Earth, you would still weigh 90% of your weight on Earth. Being at 90% of one’s usual weight is a long way from being weightless, so why do astronauts on the ISS float? Essentially, they’re not really floating; they’re falling. The ISS, as an Earth satellite, is orbiting the Earth. This means it’s constantly being pulled towards Earth, but, as it does so, it’s moving forward very fast, meaning it goes past the curve of the planet rather than being pulled down to the ground. Basically, as the ISS travels over the Earth, the curve of the Earth means the ground falls away at the same rate as the ISS falling towards it. Without the Earth’s gravity causing it to fall, the ISS wouldn’t have anything to keep it near Earth and would shoot off into space. Everything inside the ISS, including its inhabitants, is falling at the same pace as the ISS. Because of this, they seem to float. As the ‘floor’ is always moving away exactly as fast as they move towards it, the astronauts will never reach it unless they propel themselves. You might have heard the experience of weightlessness in orbit called ‘zero gravity’. Because gravity is still involved, though, astronauts and space agencies often call it ‘microgravity’ instead. Astronauts and parabolic flights Parabolic flights are one method used to train astronauts for weightlessness. These flights let astronauts experience the weightlessness of freefall for brief periods without leaving Earth’s atmosphere. In a parabolic flight, an aeroplane speeds upwards at a steep angle, slows down at the top of its altitude, then travels downwards again. It does this multiple times. At the top of each arc, the people aboard the flight experience weightlessness for about twenty seconds, as they’re falling at the same rate as the plane around them. You may have felt this yourself on a rollercoaster; at certain high points, as the rollercoaster begins to drop, it can feel as if you’re almost beginning to float off your seat. These brief periods of weightlessness are used to prepare astronauts for the experience of being in space. Parabolic flights are also sometimes used to perform scientific experiments in simulated low gravity without needing to leave Earth. If your experiment takes more than a few seconds to complete, though, you might have to travel to space to get it done. Astronauts and neutral buoyancy pools Neutral buoyancy pools use water to give astronauts an Earth-based experience similar to the low gravity of space. In neutral buoyancy, precise weighting means that gravity is balanced by buoyancy, so you remain suspended at the same level underwater, rather than floating up or sinking down. Being in a neutral buoyancy pool isn’t exactly the same as being in space. For example, water drags on anything moving through it, making movements slower, whereas there’s almost no resistance in space. It’s also possible to swim in water, of course, which isn’t an option open to astronauts in space. However, neutral buoyancy gives a sense of what it’s like to move around when you can’t make use of your own weight to, for example, stabilise yourself on a surface. Because of this, astronauts often practise moving or performing tasks in neutral buoyancy, wearing spacesuits. Some neutral buoyancy training facilities include full-scale mock-ups of the equipment and environments the astronauts are expected to encounter in space, such as International Space Station components. This way, they can familiarise themselves with the space station and how to move around it before travelling to the real thing. Pools can also be used to simulate other gravitational conditions, such as the low gravity of the moon. The European Space Agency’s short video ‘Moondive’ gives a quick introduction to some of the space-based tasks that can be simulated at their Neutral Buoyancy Facility. At the moment, there’s no way to simulate microgravity perfectly for long periods on Earth. However, with parabolic flights and neutral buoyancy, astronauts can get a taste of weightlessness in advance, giving them an idea of what to expect when they venture into space. If you’re interested in how microgravity affects other living things, we’ve written before about the challenges of growing plants in space. Cover image: NASA Darwin Innovation Group is a UK-based company that provides services related to autonomous vehicles and communications. If you’re interested in working with us, take a look at our careers page. If you’d like to know how we can help your organisation make use of autonomous vehicles, contact us. You can also follow us on LinkedIn or Twitter.

Space is an environment that’s very different from Earth, which means satellites need to be constructed carefully to survive and operate there. In today’s post, we’re going to look at some of the problems satellites face in space, and at how these problems are tackled. What problems do satellites need to take into account? Here are a few of the challenges that you need to bear in mind when you’re building a satellite: The satellite needs to face the correct direction. If you’ve designed a satellite to photograph Earth from a high altitude, you’ll want the cameras to be facing Earth at all times. The satellite needs to be able to handle extreme hot and cold temperatures. The satellite needs to be able to handle the high radiation levels outside Earth’s atmosphere. The satellite needs to be able to withstand or avoid space debris, which might otherwise damage or destroy it. We’ve already talked about the space debris problem in our posts ‘What is space debris?’ and ‘How are satellites powered?’, so we’ll look at the other issues here. How are satellites made to face the right way? A satellite’s orientation in space is also called its ‘attitude’, and attitude is crucial. For example, a satellite might need to face Earth in order to take photographs, while keeping its solar panels facing the sun whenever possible. If it’s facing the wrong direction, it can’t do its job or keep itself powered. Fortunately, satellites can use sensors to tell them what direction they’re facing in space. For example, they can use infrared sensors to detect the location of Earth, or use sensors containing solar cells to keep track of the sun. With the use of these sensors, a satellite can ensure it’s facing the correct direction at all times. Because it’s difficult to refuel a satellite, it’s best if a satellite can adjust its attitude without the use of fuel-powered thrusters. This may be done using reaction wheels: rotating wheels set at different angles on the satellite. Increasing or decreasing the speed of a wheel will change the rotation of the satellite. Because these wheels are controlled by an electric motor, they can be operated using plentiful solar energy rather than limited fuel. How do satellites withstand extreme temperatures? Without the protection of Earth’s atmosphere, high temperatures become higher and low temperatures become lower. The moon, for example, can swing from day temperatures of over 100°C to night temperatures of below -100°C. This means satellites need to be able to withstand conditions that most Earth-based machinery will never encounter. Space doesn’t experience temperature in the same way the Earth does, because there aren’t enough air molecules close together in space to transmit heat, in the same way there aren’t enough to transmit sound. This means conduction and convection, which are both heat transfer mechanisms that involve particles colliding, aren’t possible in space. However, radiation involves electromagnetic waves rather than particles, which means heat can still travel through a vacuum in the form of radiation. This is why the heat of the sun is able to reach Earth, despite having to pass through the vacuum of space first. In other words, although the satellite isn’t surrounded with air for the sun to heat up, the sun’s radiation can still connect with the satellite and heat it directly. You might have noticed that, in pictures, satellites sometimes look like they’re covered in some sort of shiny, crinkly material. These are multi-layer insulation (MLI) blankets, and their job is to reduce heat loss from inside the satellite and reflect back heat radiated from the sun. In this way, they simultaneously help keep the satellite from getting too warm and help keep it from getting too cold. The Parker Solar Probe is a satellite that was designed with heat protection strongly in mind, as it orbits the sun on a path that takes it through the sun’s upper atmosphere. It withstands heat by using a coolant circulation system and a thick but lightweight carbon-based heat shield called the Thermal Protection System (TPS), preventing most of the satellite from heating up. You can see the TPS demonstrated in this video from NASA. Another interesting element of the Parker Solar Probe is the design of the Solar Probe Cup, a Faraday cup used to measure details of the solar wind. As the Solar Probe Cup is not protected by the heat shield, it needed to be designed to survive very high temperatures by itself. Because of this, it was built using materials with high melting points; for example, the grids that produce the cup’s electric field were made from tungsten, with a melting point of nearly 3,500°C. However, this created new challenges; the high melting point of the grids made it impossible to draw gridlines on them using lasers, so these lines were drawn with acid instead. How are satellites protected from radiation? Cosmic radiation can have health effects for humans, so radiation shielding is hugely important for the International Space Station and any other satellites that people might inhabit. However, uncrewed satellites also need to be protected from radiation in order to, for example, preserve delicate machinery or control testing conditions. Radiation can cause crashes, memory changes or other issues in computers and other electronics, which is a problem if you rely on electronics to keep your satellite functioning. The electronics used in satellites are often radiation-hardened. ‘Radiation-hardened’ is a slightly misleading phrase, as it suggests that they’ve been hardened through exposure to radiation. In fact, radiation-hardened electronics are just electronics that have been designed to resist radiation damage. Radiation exposure is used to test radiation-hardened electronics, but it’s not part of the process of making them radiation-resistant. For example, a radiation-hardened device may have multiple memory backups that can be checked against each other. If one backup differs from the others, it may have been altered by radiation, and it can be corrected by changing it to match the other backups. The Orion spacecraft used in the Artemis I launch had four sets of flight computers to handle the possibility of radiation issues. Instruments can also be physically shielded against radiation to some extent, for example by using layers of metal. In addition to using up resources in the shield itself, however, adding shielding to a satellite will make the satellite heavier, meaning more fuel will be needed to get it into orbit. Why doesn’t the vacuum of space pull satellites apart? On Earth, if you have a vacuum inside a container and you create a hole in that container, air will rush to fill the vacuum. This can create the impression that the vacuum pulls on the air, dragging it into the container. If you conclude from this that a vacuum pulls on whatever’s around it, you might expect the vacuum of space to pull apart whatever’s there. In fact, the vacuum doesn’t pull at the air at all. The air is pushed into the vacuum by the pressure of the air surrounding it. It’s similar to opening a hole in the side of a tank of water. If you do this, water will immediately start to pour out of the side of the tank. However, this obviously isn’t because the air outside the tank is pulling on the water; the water is being pushed out of the hole by the pressure of the rest of the water in the tank. Because of this, a satellite in space won’t be pulled apart by the vacuum. Even on Earth, a metal box can contain a vacuum without collapsing. A less sturdy container, such as a plastic bottle, might collapse, but that’s because the air is pressing in from the outside without any air inside the bottle to counteract it; it’s not because the vacuum is pulling on the bottle. It’s similar to the way a plastic bottle filled with air might collapse underwater because of the weight of the water outside. In both cases, the bottle is pushed inwards by external pressure, rather than being pulled by its contents. This doesn’t mean you can ignore the fact that your satellite will be operating in a vacuum, of course. The fact remains that the vacuum of space creates different conditions from the atmospheric pressure of Earth, so you’ll want to take it into account when building satellites. For example, satellite materials can give off gas in a vacuum, a process called ‘outgassing’, which can cause problems if the gas then condenses on lenses or sensitive components. It’s important to make sure satellites are well prepared for the challenges of space. If a satellite fails after launch, it could become space debris, ultimately posing more problems for other satellites. Both NASA and ESA operate large vacuum chambers that can be used to test satellites before they’re launched. Cover image: NASA Darwin Innovation Group is a UK-based company that provides services related to autonomous vehicles and communications. If you’re interested in working with us, take a look at our careers page. If you’d like to know how we can help your organisation make use of autonomous vehicles, contact us. You can also follow us on LinkedIn or Twitter.

Our partnership with the European Space Agency (ESA) has been crucial to our work at Darwin, enabling projects like the Darwin Autonomous Shuttle and our ubiquitous communications technology. ESA’s Directorate for Telecommunications and Integrated Applications (TIA) has now published a white paper about the connected car of the future, and we’re delighted to have played a role in the paper’s creation. ESA TIA’s automotive white paper, titled ‘The Car of the Future: Connected from Space’, discusses the importance of reliable connectivity for vehicles. Modern vehicles require an internet connection for many purposes, from passenger entertainment to driver assistance features that can improve fuel efficiency and therefore reduce emissions, such as predictive cruise control. As the paper says: New digital software-based services are designed to make cars a safe, affordable, efficient, environmentally friendly, and enjoyable experience ... Connectivity is an essential prerequisite to these transformations, rather than just a nice-to-have secondary capability. Using onboard sensors and internet connectivity, the autonomous car of the future will be able to optimise its own operation and maintenance as well as the experience, convenience and comfort of its passengers. (ESA TIA, ‘The Car of the Future: Connected from Space’, p. 7) However, modern terrestrial networks alone cannot provide the level of coverage these services require. Although much of the UK is well covered, areas without terrestrial network coverage still exist, and a moving vehicle may pass through one or several of these areas during a journey. In the UK 8% of geographical areas remain without 4G services, and this level can be much higher in specific regions. Moreover, in many places poor user experience is reported, even if there is coverage. (ESA TIA, ‘The Car of the Future: Connected from Space’, p. 15) Because of this, the paper looks at how supporting terrestrial communications with satellite networks may be the key to maintaining a stable connection while travelling. Darwin’s ubiquitous communications demonstration in Cornwall helped to support this point by providing concrete data. Although Cornwall provided challenges for both satellite and terrestrial communications, Darwin’s technology made it possible to remain connected 99% of the time by seamlessly switching networks when necessary. These results are highlighted on pages 16, 17 and 27 of the paper. You can request a copy of ‘The Car of the Future: Connected from Space’ from this page on the ESA website. Darwin Innovation Group is a UK-based company that provides services related to autonomous vehicles and communications. If you’re interested in working with us, take a look at our careers page. If you’d like to know how we can help your organisation make use of autonomous vehicles, contact us. You can also follow us on LinkedIn or Twitter.

Darwin the Shuttle Runs Away, the children’s book based on the Darwin Autonomous Shuttle, has now been released in Spanish! Darwin se escapa is a picture book aimed at children between four and eight years old. It tells the story of a lively but insecure self-driving vehicle called Darwin, who, afraid of being driven, runs away to start a new life as a bus. The original text was written in English by Harriet Evans and has been translated into Spanish by Leticia García. Both versions of the book feature hand-painted colour illustrations by Alison Evans throughout. Darwin se escapa can be bought here on Amazon.es and, if you’re not in Spain, can also be found on other versions of Amazon. The English version, Darwin the Shuttle Runs Away, is available here on Amazon.co.uk. Darwin Innovation Group is a UK-based company that provides services related to autonomous vehicles and communications. If you’re interested in working with us, take a look at our careers page. If you’d like to know how we can help your organisation make use of autonomous vehicles, contact us. You can also follow us on LinkedIn or Twitter.