Earth-bound exoplanet hunter's eyes blink open
Paranal telescope array sees first light
The European Space Observatory (ESO) is reporting “first light” from the world's latest exoplanet hunter, an Earth-based optical instrument in Chile.
The Next Generation Transit Survey (NGTS) at the ESO's Paranal observatory in the north of the country will, like NASA's Kepler space telescope, try to detect exoplanets as they transit their stars.
To get the sensitivity and resolution required, the British, Swiss and German team designed the NGTS as an array of twelve telescopes with apertures of 20cm apiece. The robot scope will be watching hundreds of thousands of “relatively bright” stars (magnitude V<13), the ESO announcement says, for changes in their brightness.
Hence the importance of a high-altitude location with clear air above and low light pollution, to minimise twinkling and get the best possible view of the target stars.
The telescopes themselves are modified versions of units built by Astro Systeme Austria, with modified ikon-L cameras from Andor Technology. The cameras will use “red-sensitive deep-depletion CCDs” provided by e2v. The ESO says all the key technologies for the NGTS were demonstrated in a prototype that operated at La Palma in the Canary Islands during 2009 and 2010.
While Kepler provides more accurate measurements of stellar brightness, ESO says, it focuses on a smaller region of the sky, while the NGTS will survey more of the sky looking for exoplanets orbiting brighter stars.
The NGTS's mission will search for exoplanets from twice Earth's diameter up to “super-Earths” eight times the diameter of Earth.
The telescopes will be covering wavelengths from 600 nm to 900 nm, and planets it locates will be characterised in detail by other instruments, such as the VLT (Very Large Telescope) and European Extremely Large Telescope (E-ELT), both at Parmaal; and the James Webb Space Telescope. ®