The Diana Radar at the U.S. Army Signal Research and Development Laboratory made its now historic first contact with the Moon on 10 January 1946.
Scientists have been bouncing signals off the Moon ever since.
The results have been of great value in man-made satellite programs and developing better military radars.
Scientists have also learnt more in general about the upper atmosphere and been able to plot the terrain of the moon itself.
This was vital information, without which the Apollo 11 mission in 1969 would never have been possible.
23 years after the first radar contact Man finally walked on the Moon.
The rest as the say 'is History'
Interested in Apollo 11?
for 10 things you didn't know about the Moon landings.