What Is Now Proved Was Once Only Imagined

 The Power 

 of Imagination 

 William Blake 

 What is now proved 

1972: Apollo 17 command module floating above the moon in 1972. Notice the similarity in shape and even the similarity in construction with the module (below) in the Méliès 1902 sci-fi animated film: A Trip to the Moon. 

 Was once 

 1902: Still from the Méliès 1902 sci-fi film: A Trip to the Moon. The command module that held the astronauts was inserted into a super-gun to send it to the moon.

 Only imagined 

See my related in-depth blogs about 
The Work of the Imagination
http://deconstructingtime.blogspot.com/2016/10/the-work-of-imagination.html
and
The History of the Future
http://deconstructingtime.blogspot.com/2013/06/the-history-of-future.html