Sometimes there are profound questions in life that have to be answered, how “What does that mean?”, “Are we alone in the universe?” Or “What happens if you throw a paper plane from the international space station?” Fortunately, this third was finally answered because of course someone would at some point. A new paper from Maximilien Lying and Kojiro Suzuki from the University of Tokyo deals with the dynamics of an origami world space aircraft during the earth's atmosphere – in other words, what happens when you throw a paper level out of the ISS.
First let's go through some technical ideas that are necessary for understanding this apparently simple concept. Origami means literally folded paper in Japanese, and in this case the authors have decided to make their paper plane from a standard -a4 sheet white paper. The end result looks like something that a third grader runs out to annoy her friend in class in front of you, but with much more aerodynamic modeling.
As soon as the software model was created, it was time to test it. The ISS buys at around 400 km, so that the authors decided to start the aircraft from this height and at a speed that is similar to the ISS itself – 7800 m/s. This speed probably seems to shred a paper aircraft, but at a height of 400 km, the atmosphere is not thick enough to cause a lot of damage.
https://www.youtube.com/watch?v=pswkplmr2io
Obviously there has been this question for a long time – here is a video of 5 years ago about what would happen in this scenario. Credit – Ridddle YouTube channel
This is actually the majority of the descent back to the ground. From 400 km to around 120 km high, the aircraft remains relatively stable in view of the lack of air. However, due to its low ballistic coefficient, the level increases very quickly, which is a measure of how well it can overcome the air resistance. With its low ballistic coefficient, the level slowed down quickly and rises to 120 km in about 3.5 days.
On the slip side, a low ballistic coefficient would mean that after the atmosphere, the aircraft actually has a lower terminal speed than a cannonball. Unfortunately, it never makes it so far when, after the simulations at a height of about 120 km, the increased airtight inducer induces an uncontrollable fall and essentially sends the aircraft into an uncontrollable flight path that is familiar to anyone who has ever made one of them.
But why stop in simulations when you have a doctorate in aerospace technology and be able to build a paper plane for science? And why just build one if you can test one in a hyper-enlarged wind tunnel on your university campus? The answer is that you don't stop -why the authors built an actual paper aircraft model (admittedly with an aluminum tail) and were recorded in the Hyperhperson -Hypersonic wind tunnel from Kashiwa and High Enthalpie at the University of Tokyo to see what kind of aerodynamic forces could withstand paper aircraft.
https://www.youtube.com/watch?v=lrmtryrkw1y
In the infinite persecution of content, other YouTubers would of course try to start a paper plane from space. Credit – eager YouTube channel
You didn't make your experiments easy either. Your third-off-paper aircraft was exposed to 7 seconds, similar to the forces that were experienced during the actual re-occurrence. It was not surprising that this bent back the nose of the paper plane, but did not dissolve to his loan – at least not during this time. There were also noticeable indications that the nose and wing tips for charging and winged tips indicate that the paper level would be burned if the experiment had expired longer.
Ultimately, it was one of the purposes of this experiment to prove this. There are many mission architectures that could possibly use something similar to this paper aircraft model – the leaf experiment for exploring Venus comes to mind, but there are also many straw observations that would benefit from a slight, stable platform to make their collecting while in the atmosphere at the end of life.
The assembly of such a mission would have to require electronics and many other additions that would complicate the purity of the talent of a simple paper level that a child could have created. But sometimes science is just as much about inspiration as it is about exploration, and the results in this paper offer a nice mix of both.
Learn more:
M. Berthet & K Suzuki study on the dynamics of an origami world space level during the earth's atmospheric entry
Ut – paper boomerang is tested at the space station
Ut – floating leaves could characterize the atmosphere of Venus
Wikipedia – paper planes from space started
