Ground control to tiny radio satellite: Mission accomplished
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FUNABASHI, Chiba Prefecture–An amateur radio satellite roughly twice the dimensions of a Rubik’s Cube and engineered by students at a university based in Tokyo is now in orbit and beaming clear signals to Earth.
The satellite, one of seven developed by universities and businesses, was sent aloft Jan. 18 atop an Epsilon-4 rocket launched from the Japan Aerospace Exploration Agency (JAXA) Uchinoura Space Center in Kagoshima Prefecture.
The “NEXUS” radio amateur satellite was created by undergraduates and graduates of Nihon University’s College of Science and Technology here, where 40 or so individuals, including the students involved in the project, collectively held their breath as they watched the lift-off on a live broadcast from the campus.
Loud applause erupted as the rocket took off just after 9:50 a.m.
The next 95 minutes were nail-biting as project members monitored the post-separation motion of the satellite at a ground station installed on the university campus.
Signals sent from the satellite showing the mission was a success arrived around 11:25 a.m.
“When I heard the signal, I finally felt that our satellite was in space,” said Koichiro Yamada, a 24-year-old graduate student in the first year of a master’s program. “Many people helped us, which enabled us to launch the satellite. We will have to work hard on our mission in the days to come.”
Ten undergraduates and graduates worked with members of the Japan Amateur Radio League and Japan AMSAT Association (JAMSAT) to build the NEXUS satellite under the supervision of Yasuyuki Miyazaki, a professor of aerospace engineering.
The ultra-small device, which is shaped like a cube, measures about 10 centimeters on each side and weighs about 1.2 kilograms.
The main body was designed and assembled by the Nihon University members, whereas two of the four radio sets aboard the device were manufactured by JAMSAT.
The NEXUS project is aimed at developing a communications satellite equipped with low-cost and high-performance radio sets, said Kiyoshi Yamaguchi, a graduate student in the second year of a master’s program.
Numerous miniature satellites launched to date typically use amateur radio frequencies.
The key is the speed in which data can be downloaded. NEXUS can transmit data at about four times the conventional rate, Yamaguchi, 23, explained.
A JAMSAT symposium in 2012 in which Nihon University students took part set the stage for the project. University officials entered an open competition for satellites to be carried aboard the Epsilon-4, and were informed in spring 2017 that they were successful, sources said.
Miyazaki, 52, has helped make many small satellites in the past, but this time he limited himself to the role of supervisor on grounds that a university-based development project would not deserve its name unless undergraduate and graduate students played the central role.
Miyazaki taught the students what sort of environment the satellites would be exposed to in space and emphasized the importance of schedule management.
The satellite relies on solar cells on its sides for power. The students repeatedly had to redesign the power supply unit.
They were also troubled by noise and other problems, and often spent the night in the lab working to fix the glitches.
The satellite was finally delivered to JAXA last September.
JAMSAT’s roots lie in a predecessor group founded in 1972. It started out helping individuals keen on amateur radio satellite communications or manufacturing a satellite themselves. Japan launched its third amateur radio communications satellite in 1996, and no more were planned as JAMSAT by then had begun assisting foreign satellite projects.
However, the association decided to make an exception in this latest instance and embraced the long-cherished dream of launching another domestically produced satellite.
“It was such a tough job cramming all that technology into this compact satellite,” said Hozumi Ueda, a 63-year-old company employee from Koshigaya, Saitama Prefecture, who played a central role in making the radio sets. “I was given this opportunity to work with young students on the manufacturing process, which kept me busy but gave me loads of fun.”
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