China Builds World’s Largest Radio Telescope

China Builds World’s Largest Radio Telescope

China is taking steps towards becoming a global super-power. It is the world’s second largest economy by nominal GDP. The country also has the world’s third largest military.

So China is looking to make advances in science as well. The Asian power has a space exploration program.  And now China has the largest radio telescope in the entire world. Building of the telescope started in March 2011 and is now over. Five years later, China has achieved another number one spot.

The Five-hundred-meter Aperture Spherical Telescope

The telescope takes its name after the diameter that it has. The name is the Five-hundred-meter Aperture Spherical Telescope, shortened to FAST. It opened this Sunday in China with much enthusiasm. The second largest radio telescope in the world is at the Arecibo Observatory, located in Puerto Rico. It has a diameter of 305 meters.

The Chinese news agency Xinhua says that the cost for building the telescope was $180 million. The construction of the telescope displaced 8,000 people from where they lived. This was necessary in order to clear a 3 mile radius of radio silence around the telescope.

The telescope is going to be used for “observation of pulsars as well as exploration of interstellar molecules and interstellar communication signals”.

Pulsars are cores of stars that have imploded. They are slightly bigger than the sun. Pulsars emit radiation and with a telescope that is sensitive enough you can detect that radiation. Qian Lei is a researcher at China’s National Astronomical Observation. He says that FAST is very sensitive. In a test, the telescope detected radio waves that were from a pulsar found 1,351 light-years away.

Looking to the Future

Like other radio telescopes, FAST is also going to study interstellar molecules in relation to the evolution of galaxies. Radio telescopes can give us information about how gasses behave in other galaxies. For example, this summer, a team of scientists found a “faint radio emission from atomic hydrogen … in a galaxy nearly 5 billion light-years from Earth”. They used data from the Very Large Array. It’s a collection of radio antennas located in the New Mexico desert.

The final use of the Five-hundred-meter Aperture Spherical Telescope is going to be looking at interstellar communication signals. Better said, listening to interstellar communication signals. More simply put, what the telescope will do is listen to outer space, should it find a signal. The end goal of the FAST is searching for signs of intelligent extraterrestrial life. Qian Lei of China’s National Astronomical Observation entertained the possibility of the existence of another civilization in outer space. He said that the radio signal that it would send would be similar to the signal received from a pulsar. FAST would be able to pick up on that signal in the event that something like that would occur. It would be a first step in communication with another intelligent life form from outer space.

But attempts at communication have already taken place. SETI is a scientific organization that searches for extraterrestrial life. In 1974, the Arecibo radio telescope sent a signal into space containing various data.


Image source: here.