Space Technology and innovation

Answers to popular questions on the technology and innovation in space.

By using my knowledge of our solar system and the basic needs of living things, I can produce a reasoned argument on the likelihood of life existing elsewhere in the universe – SCN 3-06a.

By researching developments used to observe or explore space, I can illustrate how our knowledge of the universe has evolved over time – SCN 4-06a.

Yes, one of the most useful and important things that satellites do is to study the Earth itself – i.e. the satellites’ cameras point downwards instead of upwards. This is really important for, e.g. weather forecasting, monitoring the effects of climate change or global security.

Yes, perhaps one of the most important is the GPS, or Global Positioning System, satellites: these are orbiting high above the Earth (much higher than the ISS, for example), and if you have a smartphone that uses Google Maps, then the way your phone works out where you are is by bouncing signals from those GPS satellites. If we know what the satellites’ orbits are and can time how long it takes for the radio signals from your phone to travel to the satellites and back again, then your phone’s software can work out where you are to the nearest few metres on the surface of the Earth.

It folded up! Just like, e.g. a folding Maclaren buggy or pushchair; maybe you had one of those when you were a baby… Here’s a nice video that explains how it was done – and shows the Apollo astronauts unfolding their buggy:

Yes, perhaps one of the most important is the GPS, or Global Positioning System, satellites: these are orbiting high above the Earth (much higher than the ISS, for example), and if you have a smartphone that uses Google Maps, then the way your phone works out where you are is by bouncing signals from those GPS satellites. If we know what the satellites’ orbits are and can time how long it takes for the radio signals from your phone to travel to the satellites and back again, then your phone’s software can work out where you are to the nearest few metres on the surface of the Earth.

Those are really two different questions, but both are super-interesting! For the second one, “Are aliens real?” I really want to believe that the answer is “yes”. We live in a vast universe, with something like 100 billion stars in our Milky Way galaxy – and perhaps as many as a trillion galaxies in the universe. For about 30 years now, we’ve also been starting to find planets going around nearby stars, so it seems like lots of stars have planets – and we’re even starting to find planets that are similar to the Earth going around other stars! If even a tiny, tiny fraction of stars have planets like the Earth, with the right size and temperature and distance from their star to have atmospheres like the atmosphere of the Earth, then across the whole galaxy, that could still mean there are millions of Earth-like planets out there. To think that we are the only planet, out of all of that, where life has arisen doesn’t seem right to me. I like to think that life is very common in the Universe, which would mean that extra-terrestrials are real.

But do I think those ETs come to visit the Earth in UFOs? That’s a very different matter because space is so big!! Even the nearest star to our Solar System is about 100 million times further away than the Moon, so we don’t know of any way to travel those kinds of vast distances without the journeys taking hundreds or thousands of years. All of that means that I’m really not sure that the reports of UFOs are actually seeing visiting spacecraft carrying ETs from far away star systems. But, the truth is I don’t know either way – and I certainly think we have to keep looking for signs of life on other planets and even signs of ETs visiting us here on Earth.

I’m not an expert in this, but I’ve been able to find out a lot about how spacesuits are designed. You might find this website useful and there are some nice graphics too: https://www.nasa.gov/feature/spacewalk-spacesuit-basics

Here’s another really good one, too: https://www.funkidslive.com/learn/deep-space-high/space-explanation/what-are-space-suits-made-of/.

The most important thing about a spacesuit is that it must completely cover an astronaut and protect them from the vacuum of space. That means it’s got to be strong enough to be pressurised because an astronaut must take their air supply with them. Think what would happen if you kept pumping air into a balloon: the balloon would stretch and stretch and eventually burst, so you can’t have that happening to an astronaut’s space suit! That means the suit must be made of strong material that doesn’t stretch too much but is still lightweight enough that it’s not too uncomfortable to wear. A good way to achieve that is to make a suit with lots of layers, and the website links above talk about that. You could try some experiments yourself to check this out. Suppose you take a sheet of toilet tissue or kitchen towel and hold it by the corners, stretched out: it should then be quite easy, using, say a pen or pencil, to punch a hole through that sheet. If you stack, say 10 or so sheets of tissue together, on the other hand, then you’ll find it much harder to punch a hole through that. This is like how space suits use many individual lightweight layers to give a really strong material that can’t easily be punctured.

The Moon’s radius equals 1737 km, so its circumference is 10921 km. That’s about one-quarter of the circumference of the Earth. You might think that means you could run around the Moon in about a quarter of the time it would take you to run around the Earth, but it’s not quite that simple! On the one hand, because the Earth has seas and oceans, you can’t actually run all the way around the Earth without having to do some swimming along the way. But the other complication is that on the Moon, there is lower gravity (only about one-sixth the gravity of the Earth), and there’s no atmosphere. The lower gravity means that you wouldn’t weigh so much on the Moon – so perhaps that means you could run faster as your muscles wouldn’t have to work quite so hard as on the Earth. On the other hand, the absence of an atmosphere means you would have to wear a bulky spacesuit to protect you (and give you air to breathe), which would slow you down.

Now long-distance runners on Earth can run a whole marathon (about 42 km) every day for many days – in fact, some people have done this to raise money for charity, although it must be incredibly hard work after a while. But suppose that an astronaut could run a marathon every day on the Moon. It would then take them (10921 / 42) or about 260 days to run all the way around the Moon. Maybe they’d be better off driving a moon buggy instead!