In a comfortable sunny weather, the NAOJ Nobeyama Radio Observatory Open Campus 2018 was held on Saturday, August 25. The NAOJ Chile Observatory presents the exhibition of ALMA every year in Nobeyama, a sanctuary of the Japanese radio astronomy and one of the birthplaces of the ALMA project as well.
At the ALMA/ASTE booth, researchers and engineers gave explanations about the exhibitions which include posters about the latest scientific results and the importance of millimeter/submillimeter astronomy, a 1/10,000-scale diorama model reproducing the geography of the ALMA site with indicators of antenna locations, and movies of the ALMA site in Chile captured by drone.
In the mini-lectures, Seiichi Sakamoto (the Director of the NAOJ Chile Observatory), Masaaki Hiramatsu (Assistant Professor), and Yusuke Miyamoto (Specially Appointed Assistant Professor) talked about the capabilities of the ALMA telescope, difficulties in operations in Chile, and the latest scientific results of ALMA. The mini-lectures attracted the audience of 150 people in total.
As a new attraction, “radio coloring” was introduced for understanding the basics of radio astronomy. A radio telescope creates a radio image by combining the data of radio field intensity measured in various parts of the sky. In radio coloring, people are given a grid sheet with a different number on each square. The number (0 to 5) corresponds to the radio intensity based on the actual radio image obtained by ALMA observation. By filling each numbered square with a different color, a shape of an astronomical object appears showing the radio intensity measured in each part. Nowadays, making a radio image has been performed with computers acutually, but radio astronomers 30 years ago were coloring a grid sheet like this to make an image of an observed object in Nobeyama. By experiencing radio coloring, participants can understand how radio astronomers were working in the old days. Although it was not easy to complete the grid sheet with many numbered squares to fill in, radio coloring looked like enjoyable fun experience for all ages.