DIY Experiments related to space
by Ashutosh Gadre
“Space is hard, but it is worth it” — Richard Branson
This quote is absolutely true as space exploration involves a harmony of various scientific disciplines to achieve what we have done so far. Numerous advances in science and technology over the past 80 years have enabled us to do extraordinary things like putting people on the moon, sending probes to explore the outer planets, conduct experiments to prove hypothesized concepts right and much more. Most of these technologies and experiments are very complicated and require the kind of tools that we, as enthusiasts, cannot afford. But, there are a few concepts that we can explain using simple experimental setups right at the comfort of our home.
Shielding our astronauts
Radiation is an important aspect to keep in mind while sending astronauts to space. Since the earth has a magnetosphere due to its active iron core, it is able to deflect most of the harmful radiation and protect us. But, as we plan to send people to mars in the upcoming years, we have to come up with a plausible solution to this problem. Passive shielding using metals like Aluminum and other hydrogen-rich materials can be used but it increases the mass of the spacecraft which is not an efficient trade-off to consider. Active shielding using a generated magnetic field is a good way but it is not viable yet. Coming back to the title of this article, you might be wondering how this can be demonstrated at home. You just need a microwave oven, two smartphones and a Wi-Fi connection (there is no point in mentioning this in 2018).
I must mention the fact that the results of this experiment depend largely on the oven itself so you might not be satisfied at end.
o Put your phone inside the oven and shut the door. Do NOT turn on the oven at any point in this test otherwise your phone will be permanently damaged.
o Call the phone that is inside using a cellular connection. Try a call over Wi-Fi (Whatsapp, Skype or Facetime) as an alternative.
o One of those two calls (or both) should not go through because the oven is shielded using a Faraday cage.
A Faraday cage is essentially a metal mesh which creates a field that opposes the incoming electromagnetic field (microwaves in our case), hence shielding whatever is inside it. The holes in the cage must be smaller than the wavelength of the EM wave in order for it to work properly. If both these methods aren’t working for you, there might a bigger hole in the Faraday cage of your oven that is leaking radiation and hence your call is going through. But there is no reason to panic as microwave radiation leaking from the oven is non-ionizing and will not cause you any harm.
o If you want definite results, wrap your phone completely in an aluminum foil used in kitchens and that should act as a Faraday cage.
Need for spacesuits
A spacesuit is what characterizes and astronaut whenever we think about them. It serves a lot of purposes like maintaining the temperature, pressure and oxygen levels inside the suit close to the normal conditions we have on earth. Regulation of pressure is done for many reasons, one of which is related to the boiling point of water.
The boiling point of water, contrary to what some people might believe is not 100 0C. That is only true at the standard pressure of 1 atm. In space, the pressure is much lower as it has near-vacuum conditions. The boiling point of water decreases with a decrease in pressure. So, at extremely low pressures (like those in space), water can boil at standard room temperature of around 30 0C. So, if only temperature is controlled and pressure isn’t in a spacesuit, the water in our blood will start to boil.
To demonstrate this, you will only need a plastic syringe (without a needle) and it works best with warm water.
o Fill a quarter of the syringe with water and close the tip of the syringe using your finger so that it doesn’t leak. Try to make sure that there is no air gap inside the syringe.
o While closing the tip tightly, pull the piston of the syringe back. You will notice that the piston resists this because we are trying to create a partial vacuum inside.
o Let the piston slide back in once and then pull it back again. Use another person’s help either to close the tip or to pull the piston.
o Do this once or twice and the water should start to boil.
The water is boiling inside the syringe even though it is not at 100 0C because we are lowering the pressure inside by pulling the piston back.
Building an efficiently designed spacecraft that fulfills various purposes is a very crucial part of space exploration because of its immense difficulty. And learning all the physics behind it is quite challenging but there is a fun way to do it which is through a game.
Kerbal Space Program is a physics-based spaceflight simulation game that has great attention to detail which makes it impressively accurate. This is not really an experiment you can physically perform, but in my view, it should be treated like one because of the authenticity of the physics involved. It is available for Windows, Mac and Linux and there are many YouTube tutorials available in order to build and test your first spacecraft in the game. Once you master the basics, you can dive deep into the game and try to recreate real life spacecrafts and learn some of the rocket science employed in building a space shuttle.
Links to refer
2. Phone in a microwave: https://www.youtube.com/watch?v=ot4_jVFXxUU
3. Kerbal Space Program tutorials: https://www.youtube.com/watch?v=NEQ0qKa4X2Y&list=PLYu7z3I8tdEm5nyZU3a-O2ak6mBYXWPAL
-Written by Ashutosh Gadre, a student of VNR VJIET, Hyderabad pursuing B. Tech in electronics and communication engineering.
Email at firstname.lastname@example.org