Gene Sat1 Overview Built by NASA Ames Cal

Gene. Sat-1 Overview Built by NASA Ames, Cal Poly, Stanford Launched by NASA 3 U cube, 10 cm x 34 cm, 4. 6 kg First cubesat to carry biological experiment

Structure Custom frame made from 7075 Al square tube stock Frame covered in Al panels, which provide a substrate for the solar arrays Frame also provides a thermal radiation surface (“heat sink”) for the payload heater, and possibly a ground plane for the antennas

*. Sat Bus 1 U cubesat bus developed by Stanford to provide power and communications to the primary payload 6 custom PCBs: CDH, EPS, communications, and 3 ADS boards CDH and EPS use PIC 18 microcontrollers, using I 2 C for internal communication, as well as communication with payload ADS boards mounted orthogonally enable measurement of linear acceleration and spin rate on 3 axes 3 -junction (28. 3% efficient) solar cells, 4 strings, 224 sq. cm 0. 92 A (8. 3 W) in orthogonal sunlight Li ion batteries Uses permanent magnets and hysteresis rods for ACS, as well as a sun sensor based on solar cell telemetry

Payload First cubesat to carry a biological experiment Pressurized, sealed vessel Custom optical array measures gene expression in E. coli by light emitted from GFP fused to a gene associated with metabolism Once in space, E. coli are put in assay wells, sugar water is released to start the experiment Uses COTS sensors for pressure, humidity, radiation, 3 -axis acceleration, and temperature at 6 locations Closed loop heater regulates temperature to +/- 0. 5° C

Communications and Mission 2. 4 Ghz COTS S-band radio (frequency hopping) UHF beacon 18 m dish @ SRI International Max 56% successful 2 -way communication, 200 kbit/day average downlink, took > 2 weeks to download mission data PPOD Launch on 16 December 2006 by a NASA Minotaur rocket LEO, 40° inclination, 415 km Beacon detected 1 hour after deplayment, S-band functional within 24 hours 96 hour primary mission completed Operation still nominal, secondary mission ongoing 50 minute clock drift in 13 days No CPU resets in 24 days