The European Space Agency has unveiled a new telescope design based on a fly’s eye that could make asteroid spotting cheaper.
The new device, which will take multiple images of the sky in different directions using 16 separate lenses, is seen as a less-costly alternative to using telescopes that automatically track near-Earth objects (NEOs) such as asteroids and comets.
Instead of finding and following these objects at high resolution, the new technology will capture several lower-quality images covering a wider area of the sky, enabling it to automatically detect movement and alert astronomers when there is an NEO worth investigating.
The telescope is also based on a modular design to enable mass production and allow for lower manufacturing and maintenance costs.
‘This novel technology is key to the future NEO survey network,’ said Gian Maria of ESA’s Space Situational Awareness (SSA) programme.
‘The new telescopes would provide the resolution necessary to determine the orbits of any detected objects. If the prototype confirms the expected performance, it will pave the way to full procurement and deployment of the operational network of telescopes.’
Astronomers have already identified 11455 near-Earth objects, including around 1500 that are classified as “potentially hazardous asteroids”.
The fly-eyed telescope would provide performance equivalent to a 1m-diameter conventional system and a square field of view with a width and height of 6.7° – about 13 times the diameter of the Moon as seen from the Earth.
ESA says that, under favourable conditions, this should allow it to detect all objects as small as 40m in diameter at least three weeks before any potential impact with the Earth.
The fly’s eye concept was previously used to study ultra-high-energy cosmic rays at the University of Utah in the US. In this case, the entire sky was divided into 880 hexagonal pixels, each with its own cosmic ray detector module, enabling astronomers to track “showers” of cosmic rays across the sky.
ESA has already signed a €1m (£0.8m) contract with a consortium led by Italian company CGS to design the telescope, and expects to spend a further €10m building and deploying the first prototype.
‘The development of the first optical sensor specific to ESA’s NEO search and discovery activities is a fundamental step toward Europe’s contribution to safeguarding our planet from possible collisions by dangerous objects,’ said Nicolas Bobrinsky, head of the SSA programme.