Radiation Damage Has Taken the Toll on Popular GreenCube (IO-117) Satellite

 GreenCube also known as Italy Oscar 117 (IO-117) was very popular among amateur radio satellite operators as it could provide much longer distance communications than the Low Earth Orbit satellites. That was because GreenCube was a MEO or Medium Earth Orbit satellite located at about 5000 km altitude compared to the about 400 km altitude of International Space Station. Being at a higher location, GreenCube had a higher footprint and I am aware of hams from my region contacting stations in United States of America, which is impossible with Low Earth Orbit satellites. GreenCube had a digipeater which needed specialized setup compared to the usual FM satellites which I work. Moreover, the higher altitude mandated the use of more sensitive antennas and preamplifiers.


A news item posted on AMSAT bulletin board mentioned that GreenCube satellite developed by S5LAB has likely ceased functioning due to radiation damage. Of course, the GreenCube mission was highly successful as it had exceeded expectations, compared to other cubesats launched along with it which lasted only a few days. GreenCube launched in July 2022 has lasted more than two years. It is a 3U cubesat. S5LAB team has informed that the satellite is no longer responding to commands and its onboard radio is believed to have been damaged by the harsh radiation environment in Medium Earth Orbit.

As I had mentioned earlier, GreenCube had another interesting aspect. It was a platform for cultivating microgreens in space! That was the reason for the name as well. The GreenCube was carrying microgreens (Brassicaceae) seeds for an experiment on cultivation of plants in microgravity. Brassicaceae is the family of plants which includes cabbage and broccoli familiar to us. The GreenCube's pressurised compartment would autonomously monitor air composition, pressure, humidity, lighting conditions as well as plant growth using visible and infrared cameras.

No successor to GreenCube has been planned yet, mainly because launch opportunities for MEO satellites is rare. S5LAB is planning to host a webinar in collaboration with AMSAT Italia, which had taken over the ownership of GreenCube when S5LAB had planned decommissioning sometime in February 2024. That will be a great learning opportunity for all amateur radio satellite operators and I am looking forward to listening the webinar, though I did not have the opportunity to work GreenCube while it was active.

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