• Question: what happens when you build a satellite and it malfunctions when in space and falls down to the earth and how much money will you get fined because of the damage it makes

    Asked by Abu.D.stb to Sylwia, Stephen, Phil, Matt, Hollie, Helen on 13 Mar 2018.
    • Photo: Hollie Heard

      Hollie Heard answered on 13 Mar 2018:

      Satellites go through very careful planning, lots of testing, and have backup systems that can kick in if anything ever does go wrong. We try to engineer things so that they don’t, but with a complex environment like launch and space sometimes they can. If problems happen when it is in orbit, we can try to fix things remotely through software and transmission from the Earth’s surface where an engineer will essentially tell it what to do in the hope of sorting it out. We used to have more capabilities with the space shuttle of getting astronauts to actually fix problems like they did with the Hubble telescope. Astronauts on other space stations have often had to go outside and fix things too, there’s even a few spanners and screwdrivers whizzing around in orbit that have been lost along the way! These add up to the problem of space debris that is becoming more and more of a concern as it can cause damage to other spacecraft, and potentially restrict our access to space. When satellites malfunction they can move into different orbits, collide with other satellites, or break apart adding to the cloud of space junk around the Earth. A lot of space agencies and companies are working on ways to try and remove this junk at the moment. It’s not very often, but sometimes failed satellites can fall back to Earth, often breaking up into lots of smaller pieces as they travel through the atmosphere. When this happens it’s harder to judge where the parts will land. Quite often this is done intentionally though and the satellite reentry planned so that the parts fall in the ocean, much like the MIR space station and the astronaut reentry capsules you see splash down in the ocean. I don’t know if anyone has ever been fined due to damage, but I think if it were a commercial company they would probably have to help clear up and pay for any damage. It’s an interesting point, I’m going to have a look at lunchtime and see what information I can find!

    • Photo: Helen O'Brien

      Helen O'Brien answered on 14 Mar 2018:

      Very good question! We should all consider what might go wrong and what we could do about it. Good satellite design will have an “end of life” plan and will deliberately de-orbit in a controlled way, burning up in the atmosphere. But when something goes wrong, we cannot operate the end of life plan. Most of the faulty satellite will burn up harmlessly in the Earths atmosphere. I don’t know of any cases of damage or injury caused by deorbiting satellites.
      Satellites are most likely to fail at launch, so usually launch sites are close to oceans, so that failed spacecraft will fall into the sea and not onto populated areas.

    • Photo: Stephen Williams

      Stephen Williams answered on 16 Mar 2018:

      This is an important question in the space industry as once a satellite is in orbit we can’t fix it. So one thing we do is test it on the ground in various ways which gives us confidence that it won’t fail once launched. So every spacecraft will be vibration tested which is basically shaking it quite hard. Then we put it in a special oven which will take it to 50c and then down to -20c. However, this is still not enough so we put the spacecraft in a vacumm chamber for several days and test that it functions correctly. If the spacecraft fails any of these tests it has be investigated a solution found and all the tests redone. In almost all cases a satellite comes to end of life when its battery can no longer hold a charge which is normally when its about 10 years old.