| In today's astronomy lecture, |
| I'm going to talk about the need for a system to manage the movement of satellites |
| and other objects in orbit around the Earth. |
| In other words, a Space Traffic Management system. |
| We already have effective Air Traffic Control systems |
| that are used internationally to ensure that planes navigate our skies safely. |
| Well, Space Traffic Management is a similar concept, |
| but focusing on the control of satellites. |
| The aim of such a system would be to prevent the danger of collisions in space |
| between the objects in orbit around the Earth. |
| In order to do this, we'd need to have a set of legal measures, |
| and we'd also have to develop the technical systems to enable us to prevent such accidents. |
| But unfortunately, at present we don't actually have a Space Traffic Management system that works. |
| So why not? |
| What are the problems in developing such a system? |
| Well, for one thing, satellites are relatively cheap these days, |
| compared with how they were in the past, |
| meaning that more people can afford to put them into space. |
| So there's a lot more of them out there, |
| and people aren't just launching single satellites |
| but whole constellations, consisting of thousands of them designed to work together. |
| So space is getting more crowded every day. |
| But in spite of this, one thing you may be surprised to learn |
| is that you can launch a satellite into space |
| and, once it's out there, it doesn't have to send back any information to Earth to allow its identification. |
| So while we have international systems for ensuring we know where the planes in our skies are, |
| and to prevent them from colliding with one another, |
| when it comes to the safety of satellites, |
| at present we don't have anything like enough proper ways of tracking them. |
| And it isn't just entire satellites that we need to consider. |
| A greater threat is the huge amount of space debris in orbit around the Earth - |
| broken bits of satellite and junk from space stations and so on. |
| And some of these are so small that they can be very hard to identify, |
| but they can still be very dangerous. |
| In addition, some operators may be unwilling to share information about the satellites they've launched. |
| For example, a satellite may be designed for military purposes, |
| or it may have been launched for commercial reasons, |
| and the operators don't want competitors to have information about it. |
| And even if the operators are willing to provide it, |
| the information isn't easy to collect. |
| Details are needed about the object itself, |
| as well as about its location at a particular time - |
| and remember that a satellite isn't very big, |
| and it's likely to be moving at thousands of kilometres an hour. |
| We don't have any sensors that can constantly follow something moving so fast, |
| so all that the scientists can do is to put forward a prediction concerning where the satellite is heading next. |
| So those are some of the problems that we're facing. |
| Let's consider now some of the solutions that have been suggested. |
| One key issue is the way in which information is dealt with. |
| We need more information, |
| but it also needs to be accessible at a global level, |
| so we need to establish shared standards that we can all agree on |
| for the way in which this information is presented. |
| We already do this in other areas of science, |
| so although this is a challenge, it's not an impossible task. |
| Then, as all this information's collected, |
| it needs to be put together so it can be used, |
| and that will involve creating a single database on which it can be entered. |
| As we continue to push forward new developments, |
| congestion of the space environment is only going to increase. |
| To cope with this, we need to develop a system like the one I've described |
| to coordinate the work of the numerous spacecraft operators, |
| but it's also essential that this system is one that establishes trust in the people that use it, |
| both nationally and at a global level. |
| One interesting development... |