A sun sensor determines a spacecraft’s orientation with respect to the sun.


A sun sensor determines a spacecraft’s orientation with respect to the sun. The front surface of the NewSpace Systems (NSS) NFSS-411 sensor is a synthetic sapphire window with a reflective metal coating beneath. Slits are etched in the metal and sunlight passes through them and through an optical filter onto a sensor. The charge on the photo-sensors are read by the microcontroller which processes the image and computes the sun vector. The vector and other telemetry is returned to the spacecraft through the serial interface. The NCSS-SA05 is based around a PSD analogue sensor. Each sensor comes with a specific calibration equation for maximum accuracy. The unit can be powered from unregulated DC power from the spacecraft.

• Ultra small size and low mass
• Low power
• Simple to interface
• Wide field of view
• NFSS-411: Digital architecture (Albedo immune)
• NCSS-SA05: PSD architecture
• NFSS-411: Calibration embedded
• NCSS-SA05: Simple analogue interface

• Accurate determination of sun-angle
• Can be used in conjunction with a magnetometer for simple attitude control
• Can be used as safe-mode sensors on gyro or star-mapper controlled systems
• NFSS-411: Four sensors can achieve full sky coverage
• NCSS-SA05: Six sensors can achieve full sky coverage

Both the NFSS-411 and NCSS-SA05 are TRL 9 with extensive in-orbit heritage. The NFSS-411 Sun Sensor has demonstrated in-orbit lifetimes of >5 years in LEO and due to its robust nature has become a preferred choice for constellation primes. To date, >300 NFSS-411 units have been delivered globally, while our NCSS-SA05 Sun Sensor has been flying since 2014, with >80 units delivered globally. Currently the NSS Sun Sensor products are baselined on 5 constellations.