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Exoplanet Hunting NGTS Telescope Array Achieves First Light

Posted by timothy on from the well-lookit dept.

Zothecula writes The Next-Generation Transit Survey (NGTS) array, built by a UK, German and Swiss consortium, has achieved first light at the Paranal Observatory in Chile. The installation is designed to search for exoplanets between two and eight times the size of Earth, studying them as they pass in front of their parent star.

1 of 19 comments (clear)

  1. Re:Not much aperture by Whiternoise · · Score: 4, Informative

    See my other post for more info - particularly the bit about why we'd use this over a satellite.

    A major pro for a dedicated array is that it doesn't have anything else it should be observing. Normally these things are very wide-field, for telescopes. SuperWASP used off the shelf SLR lenses (good ones, mind, Canon 200mm f/1.8's) to create a mosaiced wide view of the sky. They also used a lot of very expensive (Andor) CCDs. The smaller amateur telescopes, e.g. a 3" refractor, might have a focal length of 400mm or so. The field of view of SuperWASP is around 22 x 22 degrees - that is ridiculously wide. The CCDs were 2048px square so we're not talking about high magnifications on deep objects here. These systems are not fast point-point scanners. They're huge eyes watching large chunks of the sky continually, pumping out gigabytes of data every night.

    NGTS has similar specs to SuperWASP, 200mm focal length covering a field of around 10 x 10 degrees. http://www.ngtransits.org/tele.... Note that the mounts are also off the shelf, but super expensive for amateurs http://www.astrosysteme.at/.

    As I mentioned 1/1000 isn't that amazing. If you expose so your target gives you 15,000 counts and you a measurements per second then you can easily get a nice high signal to noise over a time scale of minutes. The star, once you correct it with some stable reference target and allow for atmospheric extinction, should have essentially a flat brightness so any dip is noticeable.

    After this it's a down to PhDs and Postdocs to sift through all the data, write automatic routines to generate light curves for all the stars and so on. Google sextractor, don't worry, it's SFW ;) .