How long does it take to make a satellite?

Question: How long does it take to make a satellite?
- Keywords:
  satellite
Asked by 852spag42 to Will, Betty, Isaac, Kieran, Silvia on 14 Nov 2016. This question was also asked by 583spag43, 993spag43, JOHN CENA!, Achsu, Sivakarthikeyan Remo, galaxyheart, Shifty-ninja, jedi, GhOsT.
- Silvia Pardo answered on 14 Nov 2016:
  
  As you would imagine, it depends on how big they are and what kind of modules it needs: it took the European Space Agency 3 years to build the newest Earth observation satellite (the Sentinel-3, which carries 7 different instruments and weights “only” 1250 kg), but you can build a CubeSat (which can be as little as 10 cm and weight around 1 kg ) in months.

Question: How long does it take to make a satellite?