QuakeSat: mission review By : Amber-Rose White
General Information about quakesat • Nano-Sat developed by Stanford University • Deployed on June 30, 2003 • Launched into space via a Eurockot from Plesetsk, Russia • Contact was made with the satellite approximately 18 minutes after deployment • Launch, deployment and operation of the satellite was a success • The QuakeSat was placed in an 800 km sun-synch orbit • QuakeSat ran successfully for approximately 11 months
Mission of QuakeSat • The main objective of the QuakeSat was to develop a cost effective means of predicting earthquakes via detection of the ELF (Extremely Low Frequencies) • ELF are observed as a natural phenomenon of earthquakes and are capable of being detected prior to an earthquake • QuakeSat was determined to be a cost effective means of predicting earthquakes via detection of ELF by using off the shelf components to build a cubesat
Mission Outcomes • Successfully helped predict earthquakes • QuakeSat detected ELF bursts over 8 earthquake areas in 12 months • Proved to be an excellent means of helping to predict earthquakes since the satellite is able to move and thus can get closer to the epicenter of the quakes and has better odds of detecting the ELF emitted by the earthquakes. • The problem with ground based sensors, while they run 24/7 is they are only proven effective if they are within 15km of the epicenter.
San Simeon M6.4 Earthquake • Earthquake that occurred in California on December 22, 2004 • QuakeSat helped successfully track and detect the ELF emitted by this earthquake • Nearest land sensor was over 60km away • QuakeSat was able to detect, record and transmit the unique ELF bursts that were present both before and after the earthquake • This shows how satellites can be used to provide a wide area warning
Quakesat subsystems • Electrical Power Subsystem • 2 lithium batteries, 4 solar cells, 4 double sided deployable solar cells (18% efficiency) • Communications Subsystems • BayPac BP-96A Modem and the Tekk T-Net Mini 960 radio • Attitude Control Subsystem • PAC and 4 ALNICO 8HE Bar Magnets • Command and Data Handling Subsystems • The CPU for the satellite was the PC 104 processor called Prometehus, and Linux was chosen as the OS
Solar Cells/Arrays • QuakeSat was powered mainly by deployable solar cells • Backed with thin sheets of aluminum • Found to not be sturdy, bent under slightest pressure resulting in cracks on the panels • This caused problems with the cells developing cracks during testing and handling • A possible solution was proposed by using a thicker backing which could provide better support to the solar cells as well as house the circuitry for the panels.
Miscellaneous Information • QuakeSat cost • Approximately $50K to build the actual QuakeSat as well as three engineering models • People cost was $1-2 Million • Launch cost was approximately $120 K • Originally designed to work for only 6 months worked for up to 11 months with no problems • 3 yrs and 6 months later they were still able to receive transmissions from QuakeSat
Resources • Michael’s List • http://mtech.dk/thomsen/space/cubesat.php • Useful links for more information on QuakeSat • http://www.quakefinder.com/fppt/lessons.htm • http://www.quakefinder.com/quakesat.htm • http://www.quakefinder.com/quakesat-ssite/index.htm