Construction Begins on the World’s Largest Steerable Radio Telescope

Radio astronomy has been in flux lately. With the permanent loss of the Arecibo telescope in Puerto Rico, a new global power has taken center stage in humanity’s search for radio signals – China. Recently the Chinese announced the start of work on a new milestone telescope, which will eventually make it the biggest moveable one in the world.

That title is currently held by the Green Bank telescope in West Virginia, in the US, which is part of the famous Green Bank Observatory where the recently deceased Frank Drake originally presented his now-famous equation. Located in a designated National Radio Quiet Zone, the Green Bank Observatory has been the backbone of the field of radio astronomy since its first observations in 1958.

The Green Bank Telescope is the centerpiece of the Observatory, serving as the Observatory’s primary observational instrument since its first light in 2000. Coming in at an impressive 100m diameter, it is still steerable, meaning it can access an impressive 85% of the local sky. In the last few years, the telescope, along with the Observatory more generally, has been spun off into a non-governmental, non-profit organization to seek out private funds to continue its operation after the National Science Foundation’s budget threatened to cut funding to it.

Event Horizon discusses how astronomy will play out in the near future.
Credit – Event Horizon YouTube Channel

Compare that to the new QiTai (QTT) Radio Telescope under construction in China. Coming in at 110 meters, it is 10% larger than the Green Bank and, therefore, able to capture more frequency data. It will also be able to cover 75% of the observable sky from its vantage point in Xinjiang in Northwest China.

Xinjiang itself has been the focus of intense international scrutiny as of late, primarily dealing with how the Chinese government has treated the Uygurs, an Islamic minority, that live there. But that hasn’t stopped members of the government from choosing this site to build one of the world’s most powerful radio telescopes. The site might also eventually be a National Radio Quiet Zone, though that has not been approved by the authorities yet. Either way, the area’s surrounding mountains and relative lack of development already provide some level of protection from errant electromagnetic noise.

This isn’t the only recent effort that China has been making in radio astronomy. It currently holds the record for the largest fixed radio telescope as well, with the static FAST radio telescope coming in at a whopping 500 m diameter. However, FAST’s fixed orientation means it can only access a small part of the sky.

UT video on the QTT’s stationary cousin – the FAST telescope.

QTT’s novelty combines its size and maneuverability, though it will take a while before it is fully operational. Six years of expected construction time lies between now and the telescope’s first light. At that point, radio astronomers can welcome a new instrument to their universe-observing arsenal.

Learn More:
CGTN – China starts building world’s largest steerable telescope
UT – 64 Radio Telescopes Come Together to act as a Single Giant Observatory
UT – If you had Radio Telescopes for Eyes, one of the Biggest Things in the sky Would be a jet of Material Blasting out of a Nearby Galaxy
UT – Fast Radio Bursts can now be Tracked in Real-Time

Lead Image:
Artist’s depiction of the QTT radio telescope.
Credit – CAS