News and Views

News and Views on “Estimation of Solar Observations with the Five-hundred-meter Aperture Spherical radio Telescope (FAST)”

Source: 李向华 Posted: Dec 28, 2022

Author: Jin-Tao Luo

National Time Service Center, Chinese Academy of Sciences, Xi’an 710600, China;

The Sun is the nearest star to our planet Earth. Great efforts have been made to observe and study the Sun. Among ground-based observing facilities, radio telescopes play an important role in the area of solar astronomy. Large-size single dishes like Green Bank Telescope (GBT) and arrays like Very Large Array (VLA) have been employed to observe the Sun in the radio band. As the current largest single dish radio telescope, Five-hundred-meter Aperture Spherical radio Telescope (FAST) has attracted great interest in how much its unparalleled sensitivity could improve solar radio observations.

This letter addresses using FAST to observe the radio Sun. The most important rule is to keep the receiving system safe, which means the threshold of the receiving system should not be exceeded. The power FAST would receive from the Sun was calculated carefully in this letter, while taking both the quiet and burst Sun into consideration. The calculations suggest the received power would exceed the threshold of FAST’s 19-beam receiving system. In addition, the power received with FAST’s sidelobes were calculated to provide information on how much angular separation should be maintained to conduct safe solar observations with FAST.

This letter provides a clear answer to those who hold great interest in studying the Sun with FAST. Additionally, this letter suggests angular separations from the Sun which are useful for keeping FAST safe during other observations.