• Question: Does cryogenics work and if so how?

    Asked by Annie to Heather, Helen, Hugh, Jane, Julian on 7 Nov 2014.
    • Photo: Julian Onions

      Julian Onions answered on 7 Nov 2014:

      Depends what you mean by cryogenics.
      Cryogenics is the study of very very low temperatures.
      We can make temperatures very very low, within a billionth of a degree or absolute zero (which you can never reach).
      There are a number of applications of this, so it really depends which aspect you mean. We can definitely get to very low temperatures, what you do with them is up to you!

    • Photo: Jane MacArthur

      Jane MacArthur answered on 7 Nov 2014:

      “Cryogenics” is often (wrongly) used in fiction meaning “cryonics”, which is the idea of freezing an animal or human with the idea of bringing them back to life at some point in the future – perhaps most famously used for Han Solo in Star Wars “The Empire Strikes Back”!
      There are a few companies in the world that offer the service (at hefty fees, as storing someone at a temperature of -196C indefinitely is extremely expensive!). The process can only be started when someone has been declared clinically dead. The freezing process causes some damage to the body and there is currently no method of reversing it and reviving people ‘stored’ in this way, but the hope is that future technology may have options we can’t currently imagine, and perhaps retrieve memories and personalities even if other parts are damaged. As we don’t fully understand the brain, we don’t know if the freezing process leaves any of it viable.
      This is not my area of expertise but the wikipedia is pretty interesting:
      http://en.wikipedia.org/wiki/Cryonics

    • Photo: Helen Johnson

      Helen Johnson answered on 9 Nov 2014:

      Cryogenics is the production and study of materials that are really, really cold – close to absolute zero or minus 273 Celsius (the temperature that the atoms actually stop moving – it’s impossible to get this cold). The most common examples are liquid nitrogen/helium – there’s quite a good explanation here on how they cool down these gases far enough for them to turn liquid http://www.brainstuffshow.com/blog/how-do-they-make-liquid-nitrogen/

      A combination of liquid hydrogen and liquid oxygen was used in NASA’s space shuttle as rocket fuel. CERN use liquid helium in the Large Hadron Collider to cool the superconducting magnets used to deflect particles (these conduct electricity with no resistance and produce really strong magnetic fields). Cryogenics is also used in astronomy to cool down the sensors on our telescopes. This is really important in the infra-red, because we don’t want to detect the instrument’s own heat, which would be at the right wavelength! 🙂 We want our detectors to be as sensitive as possible to be able to record weak signals.

    • Photo: Hugh Osborn

      Hugh Osborn answered on 11 Nov 2014:

      We are actually really good at cryogenics, the science of freezing stuff! In fact labs here on Earth can get colder than anywhere else in the entire observable universe.

      We get to those ridiculously low temperatures (a few millionths of a degree above absolute zero, the lowest a temperature can go) using a variety of different ways, including cooling liquid Helium using pumps and even using lasers. It’s an incredibly interesting field.

Comments