How high up do you need to be to get into space?

Question: How high up do you need to be to get into space?
- Keywords:
  atmosphere,
  space
Asked by paca532tart on 16 Sep 2025.
- Jade Gray answered on 16 Sep 2025:
  
  Space does not have one single defined height. There are many layers to the atmosphere above Earth and it gradually thins out the further you get away. It isn’t a harsh boundary. A widely used definition is the Karman line at 100km above the Earth’s surface, this about 25,000 double decker buses stacked on top of each other.
- Martin McCoustra answered on 16 Sep 2025:
  
  In Europe we accept the definition that space begins at around 100 km. Interestingly, in the US, the definition of space is anything above 50 km. So it depends where you are!
- Ieva Jankute answered on 17 Sep 2025:
  
  High enough that your spaceship can start orbiting the Earth without immediately being pulled down back to it by the Earth’s gravity, from that moment onwards, you can also experience weightlessness!

Question: How high up do you need to be to get into space?