05 Jul 2002
The European Space Agency's first small satellite has beamed back its latest set of spectacular images of the Earth's surface.
Weighing only 97 kg and having dimensions 60x60x80 cm, PROBA includes some of the most advanced on-board processing technology ever used on satellites to provide full autonomous operation. It operates with limited intervention from the ground, autonomously performing everyday tasks such as navigation.
The detailed images are all thanks to a compact high-resolution imaging spectrometer (CHRIS). At 14 kg, this is the largest piece of kit on PROBA and was developed by SIRA, UK.
CHRIS provides multispectral data of the Earth's surface reflectance in the visible and near-infrared spectral regions. The spectral bands are fully programmable within the range 415 to 1050 nm and up to 19 frequency bands can be acquired simultaneously at full resolution. Each band has a spectral resolution of 5 to 12 nm and a spatial resolution of 20 m at nadir (the lowest point directly below the satellite).
Other instruments in the payload include: a high-resolution camera; a wide-angle camera; a space radiation environment monitor and a debris in-orbit evaluator. PROBA is also the first satellite to use an autonomous star-tracker as the only source of altitude measurements.
PROBA is an ESA demonstrator satellite and is set to lead the way for future "small" missions.
Jacqueline Hewett is news reporter on Optics.org and Opto & Laser Europe magazine.