ESA scientists develop revolutionary space camera
Scientists at the European space agency (ESA) have developed a new camera that is set to revolutionise the way astronomers observe the universe. 'S-Cam' is the latest result of a decade-long project by ESA to develop the next generation of detectors for space missions. The camera makes use of a superconductor, a material that loses its natural resistance to electricity at low temperatures and can be used to record photons, or light particles, to a very high degree of accuracy. 'By 1992 to 1993 we understood theoretically that superconductors would be sensitive in the optical and near-infrared regions of the spectrum,' explains Tone Peacock, head of ESA's science payloads technology division. 'In the case of a superconducting camera, each individual [photon] is detected. Not only that, its time of arrival and its colour is measured.' This ability to 'tag' the colour and arrival time of each photon, coupled with the increase in speed the new camera brings, is expected to revolutionise astronomical observations. Astronomers currently rely on CCD cameras (charge coupled devices) to peer into outer space. CCD cameras, however, cannot measure colour and can only measure the brightness of a collective mass of photons. S-cam records each photon as it arrives, then passes the information to a computer where a database of information is compiled. Using this data, astronomers can look for variations in the brightness and colour of celestial objects on time scales of just a few milliseconds. This will allow them to study rapidly-varying celestial objects such as the optical explosions associated with gamma ray bursts and the visible light emitted by pulsars, the dead hearts of stars. The S-cam prototype has been successfully tested at ESA's ESTEC research laboratories in the Netherlands.