It’s with great pleasure and pride we are able to publish an article penned by the only swede that have experienced space up-close – professor and astronaut Christer Fuglesang. Christer gives us unique insights how weightlessness in space works and affected his life during his two historic NASA missions. He also tells us about his exciting project MIST and how Piezo LEGS® plays a critical role.
Weightlessness in space! The most amazing experience by being in space is weightlessness. Everything is different. There is no up, no down. It is easy to move around, but at the same time, a lot of the usual daily life becomes difficult. You can’t put things on a table, can’t take a shower, can’t drink out of a glass. Weightlessness is the most fun factor in space, but sometimes what you most of all long for is a bit of weight to help you out.
Experiments during weightlessness in space
However, in the weightlessness of space there are so many things you can do that is impossible on Earth. You can have fun playing with water bubbles, investigate angular momentum conservation and do an amazing amount of unique research in many fields from fundamental physics to biology and medicine. Look at this impressive list of experiments on the International Space Station, ISS! Not all of them, though, utilizes weightlessness in space for their research. It could also be the views of the Earth (breathtaking, I can ensure) or space itself.
Astronauts love being in space and explore how it is. Some though, are more curious than others. One that particularly stands out is my good friend Don Pettit. A scientist and a handyman at the same time, he has conducted many self-made experiments during his times on ISS. Have a look at this collection of his “Saturday Morning Science Videos”.
Weightlessness in space is also a big challenge for technology. Just because a device works on Earth, it is definitively not sure it will work in a spacecraft. And if it is to be used outside, in open space, the device must also deal with vacuum, radiation and possibly extreme temperature variations.
Project MIST – MIniature Student saTellite
At KTH (Royal Institute of Technology) we are building a small satellite, MIST (MIniature Student saTellite). It has several goals: First of all, it is a learning project. To give students an opportunity to experience and learn how to actually design, build and run a satellite project under professional leadership. Secondly, it offers scientists a chance to send small experiments to space and finally it offers companies a possibility to test and verify technology in the challenging space environment. For a company it can be a game changer to show that your technology works in space, as well as it is a very inspiring challenge to prove it.
Piezo LEGS® handles the difficulties of space
Although MIST is only 10 x 10 x 30 cm3, it will carry eight payloads (including a camera). One of the payloads is a Piezo LEGS® precision motor. Verifying that this one-dimensional piezo motor can work for a long time in space will open the door for many applications on other satellites, including the extremely challenging LISA project for future studies of gravitational waves.
The MIST project started in 2015 and has already involved around one hundred students. Being dependent on students – most who only works on the project for one semester – makes it difficult to do precise schedules, but MIST should be launched by the end of 2019 and be alive in space for at least a year.
Misunderstanding about weightlessness in space
A final comment on weightlessness in space: It is a common misunderstanding that weightlessness in space is due to absence of gravity. However, that is not the case. It is due to nothing counteracting the gravitational pull from Earth that gives the weightless condition. Weightlessness in space is actually free fall. But due to the extremely high speed of the satellite (exact how much depends on orbit altitude, but ISS for example travels with almost 8 km/s), the pull from Earth only curves the trajectory and the satellite keeps falling over the horizon, so to say. It is worth mentioning that if you jump out of an airplane, your speed will very fast stabilize due to the air drag and you are not in free fall anymore.
On the other hand, if you want to be weightlessness for a short while (just a few tenths of a second), just make a small jump! The short time you are in the air, you are in free fall and thus in weightlessness. But unfortunately the time is too short to experience all the fun stuff described above.
Director KTH Space Center