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Elementary Schoolers Tracking STMSat-1 While Awaiting 70 Centimeter Signal

05/20/2016

[UPDATED 2016-05-23 @ 1327 UTC] Pupils at St Thomas More (STM) Cathedral School in Arlington, Virginia, have begun tracking the orbit of STMSat-1, the 1U CubeSat they built and which was deployed on May 16 from the International Space Station. It is object 41476. After being place in orbit, the CubeSat had continued roughly in the same orbit as the ISS and of other satellites deployed on May 16. STMSat-1 STM Education Manager Emily Stocker at St Thomas More told ARRL on May 19 that STMSat-1 will turn itself on once its batteries have charged fully and its mechanized antennas deploy.

Some satellite enthusiasts had expected STMSat-1 to come alive within 45 minutes of being placed in orbit — and, in any event, they may have been listening in the wrong place. The reasons are still unclear, but Stocker said the school's NASA contact indicated they should listen on 437.000 MHz, instead of on the IARU-coordinated frequency of 437.800 MHz. This led to a lot of confusion on the part of those trying to pick up a signal from STMSat-1, which is supposed to transmit 9600 bps GMSK telemetry and, eventually, SSTV images of Earth. 

"Many people were wondering why it was "changed" to 437.000, and that was because NASA thought we may be able to hear it there instead," Stocker told ARRL. 

She said NASA later advised those following STMSat-1 developments to go back to listening on 437.800 MHz but to stay up to date on developments via the CubeSat’s Twitter feed, @STMSat11.

The satellite is the first to be designed and built by grade schoolers, who were supported by NASA technical advisors and local radio amateurs. STMSat-1 was transported to the ISS in a December launch. The kit-built satellite initially had been set for release into space in mid-February. That deployment was postponed until early March, however, before being put on hold again. The satellite project is part of the school’s STEM (science, technology, engineering, mathematics) education initiatives.

NASA’s Technology Demonstration Office provided the school with a mobile “clean room” for the construction period and has been advising the school on tracking the satellite. The space agency also provided the school with a ground station antenna to receive its 70 centimeter signals, once the satellite comes to life. NASA engineers programmed the operating frequencies for the transmitter in early 201 and have been working with the school post-deployment. 



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