NASA’s Juno spacecraft, which in 2013 listened for earthbound radio amateurs sending “HI” in coordinated, very slow-speed CW, now is circling Jupiter. In a first-of-a-kind for an interplanetary spacecraft, Juno was able to detect 10 meter Amateur Radio signals on October 9, 2013, as it looped past Earth for a gravity-assisted boost on its way to Jupiter. Juno arrived at the solar system’s largest planet on July 4.

At the time of the Amateur Radio experiment in 2013, the spacecraft was about 37,500 kilometers (23,250 miles) away, and the signals it received were reported to have been just at or above the noise level. The object of the experiment was to see if Juno’s onboard “Waves” experiment would be able to detect the collaborative RF. According to the University of Iowa, after the flyby the Juno team evaluated the Waves instrument data containing the messages.

“We believe this was the first intelligent information to be transmitted to a passing interplanetary space instrument, as simple as the message may seem,” said Bill Kurth, a University of Iowa Researcher and Lead Investigator for the Waves instrument. “This was a way to involve a large number of people — those not usually associated with Juno — in a small portion of the mission.”

Kurth said in 2013 that the activity had raised awareness of the mission, and that some radio amateurs had indicated plans to follow Juno through its science mission to Jupiter.

The objectives of the Juno mission are to understand the origin and evolution of Jupiter, look for solid planetary core, map magnetic field, measure water and ammonia in deep atmosphere, and observe auroras. The spacecraft was to make 33 orbits of Jupiter. It will explore Jupiter’s northern and southern lights by flying directly through the electrical current systems that generate them.