SIS_5_19-40_x 15.05.2007 16:59 Uhr Seite 19 Feature article Looking through the Earth’s atmosphere from the ISS Image courtesy of ESA/Thomas Reiter Image courtesy of ESA/Thomas Down to Earth: interview with Thomas Reiter Shortly before Christmas 2006, German ESA astronaut Thomas Reiter returned from the International Space Station. A month later, Barbara Warmbein asked him about his trip, the experiments he did – and how to become an astronaut. Image courtesy of NASA homas Reiter, German astronaut Tfor the European Space Agency (ESA)w1, is a true veteran of space flight. The 49-year-old father of two boys has spent more hours in space than any other ESA astronaut – almost a year in total, with 179 days on the Russian MIR space station in 1995 and 171 days on the Inter- national Space Station (ISS) in 2006. A few days before Christmas, he returned to Earth, having successfully completed a six-hour spacewalk (or extravehicular activity), collecting data for many European experiments on board the ISS, and helping to pre- pare the station for the arrival of the European module Columbus, due for launch later this year. I spoke to him Thomas Reiter during the spacewalk on 3 August 2006 by telephone at the European Astronaut Centre in Cologne, Germany. What kind of effects did you feel? helps a lot in accelerating the recov- There are basically three systems in ery process. You need to keep your How long did it take you to the body which are affected: the muscles trained while weightless, recover from your long trip vestibular (balance) system, which otherwise they would disappear. But into space? shows the most pronounced effect; in the first hours after landing, the The first severe effects were still the orthostatic system, which controls effects are pretty pronounced. perceivable the morning after land- blood pressure and becomes apparent ing, but then recovery progressed after landing, when you stand upright What do astronauts do when they are very nicely. Right now, four weeks for a long time and get dizzy easily; on Earth? What are you doing at the after landing, I don’t feel anything. and the muscles, which need to re- moment, apart from giving interviews? So within three to four weeks the adapt to gravity. Of course I did a lot At the moment, the most important effects are almost over. of physical exercise in orbit. This task is to prepare all the technical www.scienceinschool.org Science in School Issue 5 : Summer 2007 19 SIS_5_19-40_x 15.05.2007 16:59 Uhr Seite 20 Image courtesy of NASA Thomas Reiter works on a cooling line on the International Space Station debriefings for the scientists, opera- debriefings with our Russian used to improve these for future tions people and management. partnersw3. space exploration, in which ESA cer- tainly will take part... going back to Does that mean giving them results Did you find anything specific that the Moon, or then further in the of the experiments? could be improved? future, going to Mars. Not only results. I don’t work Of course, there is always some- on results of scientific experiments thing to be done. Our intention was to What did you find most impressive because that is done by the scientists prepare the operations team for the during your latest mission? themselves. But they like to know arrival of the European experiment The most exciting moments are under what conditions the experi- module Columbus and especially the certainly the launch and doing an ments were executed. And of course immediate start of an operation to extravehicular activity. there are a lot of technical questions make full use of Columbus. Based on from our systems and operations the last six months that I have been Isn’t that scary? people, for example about how they on the ISS, I think we can improve a It’s not scary, no. But it’s really very, can improve the scheduling to make few things, squeezing a few hours in very exciting and everyone who has work on the ISS as efficient as possi- here and there by streamlining the the chance to be up there looks for- ble – to get as much time as possible scheduling process. It is interesting to ward to leaving the station for a few for scientific work. These kinds of look at these multitudes of systems hours at least. There are interesting debriefings are done with every that are necessary to make a space moments inside as well, catching agency. I started that in Houston station. These include life-support beautiful views of the Earth or of the with NASAw2, now this whole systems, altitude controls, thermal- starry sky. And there’s the re-entry. process is taking place here at ESA, control systems and so forth. And the Those are the main highlights from a and in two weeks I will have the experience we have gathered can be personal, emotional point of view. 20 Science in School Issue 5 : Summer 2007 www.scienceinschool.org SIS_5_19-40_x 15.05.2007 16:59 Uhr Seite 21 Feature article But the work is of course the most We had a biological experiment Another area of study was the cardio- important thing. Doing all these great on the growth of plants, to help us vascular or vestibular system. So I experiments, and working at the fron- understand the processes that happen worked on a really wide variety of tier of all these research projects, is at the molecular level. The objective is activities. really very exciting. Being on board a not only to grow plants in weightless- space station itself is already some- ness, but to enhance agricultural out- You said you also had educational thing very special. It takes a lot of sys- put by analysing how plants grow experiments. Can you describe these? tems to keep the ISS running, and, and by improving these processes and We had an experiment called the even with three people, we have to making them resistant to particular ‘Oil Emulsion Experiment’. It was a work hard to maintain these systems conditions. plastic tube containing water and oil; so that the station is a place where We also had a physics experiment the oil was coloured red, and of people can live. But with each addi- called ‘Plasma Crystal’, which has a course the water was colourless. You tional crew member, the relationship huge range of possible applications. can observe how these two liquids – between maintaining the station and At the moment it is still at an experi- which do not mix with each other – producing scientific results will shift mental stage, with scientists trying to behave in weightlessness. Here on much more towards the scientific work. understand how dynamics are affect- Earth, the water is at the bottom of ed by weightlessness. There could be the tube and the oil, which has a Which specific experiments spring applications in a lot of areas, like the lower density, is on top. In weight- to mind? production of semi-conductors or lessness, the oil forms bubbles in the In general, I was performing experi- building fusion power plants, so this water. The experiment consisted of ments in the areas of life science, is a very interesting field. shaking the tube to try to make an biology, physics and astrophysics. We For me as an engineer, it’s interest- emulsion and then observing how the also had some educational projects, ing to see that even today there are a oil behaves over time. All this was which was interesting because I lot of processes in our body that are filmed. A lot of school students all remember very well when I was a not very well understood. We had over Germany performed the experi- school-child and followed all these experiments on our immune system: ment more or less at the same time. space-flight activities. how it or certain functions of it work. They made hypotheses about how the water and the oil would behave and then they watched the video from the ISS. They could then test their Image courtesy of NASA hypotheses. Together with my university, University Neubiberg, we carried out some small experiments showing the stability of rotational motions. For this purpose I had a little aluminium cube with me. It had different moments of inertia, and I rotated this cube around the three different axes. All of this was filmed. You can clearly see that if you rotate this cube around two of its axes, the rotation is stable, but around the third axis the rotation is instable. That experiment was intended for school students in grade 10 (ages 15- 16) and above, and for first-year uni- versity students. I think it’s interesting for pupils and students to see these practical applica- tions of weightlessness, which would be very hard to demonstrate here on Earth. Thomas Reiter during the spacewalk on 3 August 2006 www.scienceinschool.org Science in School Issue 5 : Summer 2007 21 SIS_5_19-40_x 15.05.2007 16:59 Uhr Seite 22 Image courtesy of NASA Exercising on board the ISS How did you prepare for your stay in however, there is quite a lot of was in the pool today to prepare for the ISS? What did you do to prepare preparation. We use big pools for my extravehicular activity.” My for weightlessness and for the this purpose. NASA has a huge pool younger son, who is nine years old cramped conditions there? in Houston, where you prepare for now, occasionally has some additional The training takes a lot of time.