Next-Generation Transit Survey

24°36′57″S 70°23′28″W / 24.61583°S 70.39111°W / -24.61583; -70.39111

  • Top: NGTS facility with the VLT (left) and VISTA (right) in the background
  • Middle: the facility (rendered) and night observations
  • Bottom: The array of twelve 0.2-meter robotic telescopes

The Next-Generation Transit Survey (NGTS) is a ground-based robotic search for exoplanets.[1] The facility is located at Paranal Observatory in the Atacama Desert in northern Chile, about 2 km from ESO's Very Large Telescope and 0.5 km from the VISTA Survey Telescope. Science operations began in early 2015.[2] The astronomical survey is managed by a consortium of seven European universities and other academic institutions from Chile, Germany, Switzerland, and the United Kingdom.[3] Prototypes of the array were tested in 2009 and 2010 on La Palma, and from 2012 to 2014 at Geneva Observatory.[3]

The aim of NGTS is to discover super-Earths and exo-Neptunes transiting relatively bright and nearby stars with an apparent magnitude of up to 13. The survey uses transit photometry, which precisely measures the dimming of a star to detect the presence of a planet when it crosses in front of it. NGTS consists of an array of twelve commercial 0.2-metre telescopes (f/2.8), each equipped with a red-sensitive CCD camera operating in the visible and near-infrared at 600–900 nm. The array covers an instantaneous field of view of 96 square degrees (8 deg2 per telescope) or around 0.23% of the entire sky.[4] NGTS builds heavily on experience with SuperWASP, using more sensitive detectors, refined software, and larger optics, though having a much smaller field of view.[5] Compared to the Kepler space telescope with its original Kepler field of 115 square degrees, the sky area covered by NGTS will be sixteen times larger, because the survey intends to scan four different fields every year over a period of four years. As a result, the sky coverage will be comparable to that of Kepler's K2 phase.[4]

NGTS is suited to ground-based photometric follow-up of exoplanet candidates from space-based telescopes such as TESS, Gaia and PLATO.[1] In turn, larger instruments such as HARPS, ESPRESSO and VLT-SPHERE may follow-up on NGTS discoveries with a detailed characterization to measure the mass of a large number of targets using Doppler spectroscopy (wobble method) and make it possible to determine the exoplanet's density, and hence whether it is gaseous or rocky. This detailed characterization allows to fill the gap between Earth-sized planets and gas giants as other ground-based surveys can only detect Jupiter-sized exoplanets, and Kepler's Earth-sized planets are often too far away or orbit stars too dim to allow for the planet's mass determination. NGTS's wider field of view also enables it to detect a larger number of more-massive planets around brighter stars.[6][7]

  1. ^ a b Cite error: The named reference Wheatley-2017 was invoked but never defined (see the help page).
  2. ^ Cite error: The named reference NGTS first light was invoked but never defined (see the help page).
  3. ^ a b Cite error: The named reference ngts was invoked but never defined (see the help page).
  4. ^ a b Cite error: The named reference Wheatley-2013 was invoked but never defined (see the help page).
  5. ^ Cite error: The named reference Queens-Uni was invoked but never defined (see the help page).
  6. ^ Cite error: The named reference NGTS Prototyping was invoked but never defined (see the help page).
  7. ^ Cite error: The named reference sciencemag-2015 was invoked but never defined (see the help page).