Aha, two questions in one!


I think we already are in the era where we have push buttons for almost everything. The fashion in the Victorian era was levers - think Frankenstien bringing his monster to life. In the early twentieth century it was dials and sliders - think early calculating machines. Gradually coming into the electrical age where switches were the thing often hundreds of switches as each circuit need one switch - think stage lighting in the 1950s. With the advent of miniaturised electronics, where one switch could be used to control many circuits, switches were reduced in numbers and started to have the form of a button.


As time goes on the use of buttons is improved, VHS remote controls from the 1970s were covered in them, as was the fashion, leap forward to the 21st century and we see Apple making extremely efficient use of a single button on their devices.


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As for the second question, we have been in the age of jet technology since 1928 when Frank Whittle first showed working drawings of a practical turbo jet - or 1937 when one was first built - or 1939 when an independent line of research came up with the idea in Germany and built the Heinkel He 178.


Jet flights now travel all over the world taking civilian, military and commercial cargo, it is said that at least 15,000 jet aircraft are actually in the air at any one time - surely this then is the jet age!


Don't confuse jets with rocket power, all missions to space are, at least at some point, powered by rockets.