[jamsat-news:3906] GreenCube(IO-117)運用終了の模様

[Mikio_Mouri]

残念なお知らせです。
貴重なDXを楽しませてくれたGreenCube(IO-117)ですが、機能を停止した模様
と、9月15日付のAMSAT-UKのニュースで案内がありました。
　　[Information from Piero I0KPT via Facebooks Greencube Group]

この衛星は、Medium Earth Orbit (MEO)という軌道に必然の強い放射線の影響
を受けてきました。10日ほど前のrebootでは異常は見られなかったものの、その
後無線系統が破壊され、応答しなくなったものと思われ、回復は悲観的です。
同時に放出された他のCubeSatが数日で機能を停止した中で、GreenCubeは素晴
らしい成果をあげました。
この衛星の後継は、特殊な軌道への打ち上げ機会が得られにくいこともあり、未
定です。(VK9QOの運用は、貴重な機会となりました。)
何回かの運用打ち切りの圧力のなかで、最後までアマチュア無線運用に努めて下
さった　Italia Space Agency, S5LAB, AMSAT Italia の各位にお礼申し上げます。
JA3GEP 毛利幹生

15 Sep, 2024  GreenCube (IO-117) Update
[Information from Piero I0KPT via Facebooks Greencube Group]

The GreenCube satellite, developed by S5LAB, has likely ceased 
functioning due to radiation damage. After a successful mission that 
exceeded expectations, the satellite is no longer responding to 
commands, and its onboard radio is believed to have been compromised by 
the harsh radiation environment in Medium Earth Orbit (MEO).

Approximately ten days ago, GreenCube experienced a reboot, and 
telemetry data from the event did not indicate any anomalies. However, 
the S5LAB team now suspects that the satellite’s radio was damaged, 
leading to the current communication blackout. MEO is notoriously 
challenging for satellites due to its high radiation levels, and 
GreenCube was not the only satellite affected. Several other CubeSats 
launched alongside it only lasted a few days, making GreenCube’s 
extended mission duration a remarkable achievement.

Despite ongoing efforts to send commands and reactivate the satellite, 
the team remains pessimistic about restoring GreenCube’s functionality. 
The satellite’s survival in the hostile MEO environment is seen as a 
testament to its robust design, but the likelihood of recovery is slim.

At this time, no successor to GreenCube is planned, primarily due to the 
infrequency of launch opportunities to MEO. Launches to this orbit are 
rare, which complicates the prospect of future missions.

In response to the satellite’s success and the interest it generated 
among radio amateurs, S5LAB has promised to host a webinar in 
collaboration with AMSAT Italia. The event will provide insights into 
the GreenCube mission, sharing the challenges and triumphs of the 
satellite’s journey. This is an opportunity for the amateur radio 
community to learn more about the satellite’s impact and the technical 
details behind its impressive mission.

While GreenCube’s operational life may have ended, its contributions to 
satellite technology and amateur radio will be remembered as a 
significant milestone.