GLT Astronomical First Light!!!
After the GLT antenna construction finished and all the instruments,electricity, and electronics had been installed, we officially started the antenna commissioning from Dec. 1st, 2017.
We first used an optical telescope that is installed on the antenna to catch the Moon. Guided by the shadows of the subreflector and the quadrupod legs made by the Moon light, we successfully detected the Moon with the optical telescope. With this, we roughly derived a first pointing model, and performed an all-sky optical pointing. In the meantime, an artificial radio source (beacon) was installed on the South Mountain, about 3 km away from the telescope. With the guidance of the optical telescope image of the South Mountain, we successfully detected the first artificial radio source using the 86 GHz receiver. We then found out the antenna’s near-field focus position using the beacon with scanning the subreflector position, and moved to the theoretical far-field position. Subsequently, we successfully detected the Moon with the 86 GHz receiver as the astronomical first light of the GLT on Dec. 25th, 2017, which is less than a month after the antenna was ready to use.