sarahs mum said:
That Time the U.S. Military Launched a Half a Billion Needles to Space
https://www.youtube.com/watch?v=hJDl4dUlFiI
Want the text version? http://www.todayifoundout.com/index.php/2019/10/that-time-the-u-s-military-launched-a-half-a-billion-needles-to-space-for-reasons/
What! That disagrees with what I know. What I know is the following:
This was suggested in the earliest days of space flight. The suggestion was that needles launched into space would reflect back radio waves allowing enhanced communications around the world, much better than short wave.
This was in the days of spacecraft Echo 1, launched in 1960. “The Echo 1 spacecraft was a 30.48-m-diameter balloon of mylar polyester film 0.5 mil (0.0127 mm) thick. The spacecraft was designed as a passive communications reflector for transcontinental and intercontinental telephone, radio, and television signals.”

Echo 1 was followed by Echo 2 in 1964.
It was close to this time that the idea of launching billions of needles into space for radio communications was floated. The idea was quickly quashed because radio astronomers immediately complained that it would block radio astronomy. So it was never done. The final nail in the coffin of the project would have been Kennedy’s “we choose to go to the Moon” speech in 1962. Space needles would have blocked the communications to any spacecraft heading to the Moon.
I mean, there was probably an atmosphere test, this was after all just a variation on the radar jamming “window” project of WW2. “Chaff, originally called Window by the British and Düppel by the Second World War era”. “The idea of using chaff developed independently in the United Kingdom, Germany, the United States and Japan. In 1937”.
But never in space. So far as I know.