Thanks to the development of microsatellites, universities and independents can now launch research craft for tens of thousands of dollars, rather than the multi-million dollar price tags of traditional launches. This new class of satellite is democratizing outer space exploration and offering NASA new opportunities to study little-known regions of the Earth’s atmosphere.
Kyle Godin, an Interdisciplinary Engineering PhD student at Stevens, recently demonstrated a new method for propelling some of these miniaturized satellites. The American Institute of Aeronautics and Astronautics presented Godin with its annual Abe M. Zarem Award for Distinguished Achievement in Aeronautics for his inventive research on satellite propulsion.
Weighing in at less than 1 kilogram, picosatellites offer incredible promise to budget-conscious space explorers, not to mention some unique challenges. Among the smallest orbiters in development today, picosatellites require a much lighter and less volatile propulsion system than traditional satellites. For Godin, this meant developing a lightweight solid state propulsion method made from non-combustible materials.
There is a critical reason why volatile, combusting propellants are outlawed on picosatellites. These small devices hitch rides into space in shared payloads to spread the launch cost among participants. A single malfunction during transit could therefore destroy dozens of spacecraft, making safe propulsion a requirement.
To meet these safety requirements, Godin developed a 1cm square thruster that includes a layer of solid state sodium azide. When a picosatellite needs to make a position adjustment while in orbit, a circuit underneath the sodium azide will heat to 275°C, at which point the chemical releases a burst of nitrogen gas enough to execute a maneuver. By covering a picosatellite with these simple thrusters, the satellite can make numerous controlled position adjustments throughout its lifecycle.
Miniaturized satellites are a trending topic for university and independent researchers finally able to reach outer space without reaching into incredibly deep pockets. Incorporating the latest developments in micro-circuitry, revolutionary propellants, and even off-the-shelf consumer electronics, these devices can be fabricated and launched for a fraction of the cost of a traditional satellite.
Despite the name, many miniaturized satellites are not necessarily “small,” says Godin, referring to so-called microsatellites about the size of a washing machine. The arrival of picosatellites heralds a truly new age where academic research teams, including students, can experience the thrill of exploring space. Their low price point also allows researchers to undertake missions where the satellite is intended to have only a short life span.
The relative disposability gives picosatellites potential to explore the “ignorosphere,” a hard-to-reach level of the Earth’s atmosphere that is too high for traditional aircraft and too low for satellites. NASA is especially concerned about increasing knowledge of the “ignorosphere” as phenomenon at this level can affect spacecraft traveling to and from Earth, and may have caused the Colombia shuttle disaster in 2003. Satellites exploring at this altitude would soon crash, but not before gathering critical new data about our atmosphere.
At only a decade old, the science behind picosatellites is still young, but the possibilities are immense. “The low cost of the picosatellite provides students the chance to conduct their own experiments in outer space,” Godin says. “It’s really exciting.”
Godin conducted his research on satellite propulsion as a Master's student in Microelectronics-Photonics at the University of Arkansas (advisor: Professor P. Adam Huang). As a Doctoral candidate at Stevens, he is studying graphene-based MEMS technology, working with his advisor Dr. E.H. Yang.
Godin won the Abe M. Zarem Award for his research paper, “A Solid State Thruster for Attitude Control of Picosatellites.” The award was presented at the AIAA Aerospace Sciences Meeting in Nashville, Tenn. earlier this month. As the Zarem Astronautics winner, Godin was also invited to present his work at the International Astronautical Congress in Cape Town, South Africa this past October.
Learn more about multiscale research and education at Stevens by visiting the Nanotechnology Graduate Program.