Mission Design
The PREFIRE mission is comprised of two Thermal InfraRed Spectrometers (TIRS-PREFIRE) aboard two small satellites known as 6U CubeSats. Each CubeSat operates in a distinct sun-synchronous low-Earth orbit (531 km altitude and 97.5° inclination, at launch), with one moving northward across the equator several hours (in local mean solar time) after the other.
Instrument Specifications
TIRS-PREFIRE is a grating spectrometer with a slit projection on the ground that is aligned cross-track to the satellite motion - a so-called "push broom" configuration. The instrument contains a 2-dimensional focal plane detector array with one dimension aligned cross-track, parallel to the slit (8 spatial pixels, separated by gaps), and the other dimension containing the spectral information from each scene, perpendicular to the slit.
There are two TIRS-PREFIRE instruments, one on each CubeSat, with the following specifications:
Thermopile array | 64 channels x 8 pixels |
| Spectral sampling | approximately 0.84 μm, from 5-54 μm |
| Spatial coverage | 8 separated pixels, 11.8 km (at launch) cross-track surface footprint, multiple surface footprint overlaps along-track |
| Mass | < 3 kg |
Data rate | 12 kbps |
| Power | 4.5 W |
Mission Integration and Impact
The PREFIRE CubeSats join a fleet of Earth observation satellites operated by NASA and other space agencies. By synergizing with existing satellite missions, PREFIRE data enhance the overall understanding of polar atmospheric and surface processes that have implications for severe weather frequency, sea-ice hazards, and coastal resilience in North America and beyond.
For more information, see the project's Home Page.