Five-hundred-meter Aperture Spherical Telescope
The Five-hundred-meter Aperture Spherical Telescope (FAST; Chinese: 五百米口径球面射电望远镜), nicknamed Tianyan (天眼, lit. "Sky's/Heaven's Eye"), is a radio telescope located in the Dawodang depression (大窝凼洼地), a natural basin in Pingtang County, Guizhou, southwest China. FAST has a 500 m (1,600 ft) diameter dish constructed in a natural depression in the landscape. It is the world's largest filled-aperture radio telescope and the second-largest single-dish aperture, after the sparsely-filled RATAN-600 in Russia.
The telescope as seen from above in 2020 | |
| Alternative names | Tianyan |
|---|---|
| Location(s) | Jinke Village, Pingtang County, Guizhou, People's Republic of China |
| Coordinates | 25°39′11″N 106°51′24″E |
| Wavelength | 0.10 m (3.0 GHz)–4.3 m (70 MHz) |
| First light | 3 July 2016 |
| Telescope style | radio telescope |
| Diameter | 500 m (1,640 ft 5 in) |
| Illuminated diameter | 300 m (984 ft 3 in) |
| Collecting area | 196,000 m2 (2,110,000 sq ft) |
| Illuminated area | 70,690 m2 (760,900 sq ft) |
| Focal length | 140 m (459 ft 4 in) |
| Website | fast |
Location of Five-hundred-meter Aperture Spherical Telescope | |
| Related media on Commons | |
It has a novel design, using an active surface made of 4,500 metal panels which form a moving parabola shape in real time. The cabin containing the feed antenna, suspended on cables above the dish, can move automatically by using winches to steer the instrument to receive signals from different directions. It observes at wavelengths of 10 cm to 4.3 m.
Construction of FAST began in 2011. It observed first light in September 2016. After three years of testing and commissioning, it was declared fully operational on 11 January 2020.
The telescope made its first discovery, of two new pulsars, in August 2017. The new pulsars PSR J1859-01 and PSR J1931-02—also referred to as FAST pulsar #1 and #2 (FP1 and FP2), were detected on 22 and 25 August 2017; they are 16,000 and 4,100 light years away, respectively. Parkes Observatory in Australia independently confirmed the discoveries on 10 September 2017. By September 2018, FAST had discovered 44 new pulsars, and by 2021, 500.