For those of you who know the International Radiotelegraph code or Morse as it's popularly known, The letters HI (or more often HIHI) has for a very long time been shorthand for laughter between telegraphers. The sequence .... .. sort of sounds like it, don't you think? Anyway, it's been heard around the world but now also out of this world.
Most of us have heard by now that Spacecraft Juno has entered a Jupiter orbit after years of dancing around the inner planets picking up speed. Not as many know that back in October, 2013 Ham Radio operators around the world participated in a test of one of Juno's radios designed to explore Jupiter's radio spectrum by transmitting the letters HI in slow Morse code as Juno flew past Earth.
Using the 10 meter band, hams tuned to a specific frequency depending on the last letter in their call sign and transmitted HI slowly in synch with the Internet. The test was successful and the signal received from myriad Earthbound transmitters, most no more powerful than 100 Watts, at a distance of over 23,000 miles.
Of course Hams have been talking to the International Space Station for years, but somehow this felt more dramatic even though there was no one on board to listen or answer. Anyway 73 Juno, as one says in code: So long, best wishes.