A miniature model of the ALMA Array Operations Site (AOS) has been newly added to the exhibition at the NAOJ Mitaka Campus. The ALMA site in Chile is very far from Japan, but you can see it, in spite of a reduced size, without flying to the other side of the world.
Actually we see vast stretches of reddish brown lands in the Atacama Desert in Chile, however, the miniature model is covered with white surface so that the difference in height and texture of mountain surface are shown clearly. In the photo below, blue LED light illuminates the position of the antennas extended to the maximum size with the “MOST EXTENDED CONFIGURATION” button. Also the blue LED illuminates the position of the antennas at the minimum layout when pressing the “MOST COMPACT CONFIGURATION” button, and switch to the position of 16 Japanese antennas when pressing “MORITA ARRAY” button. When pressing the buttons of “AOS TECHNICAL BUILDONG” and two mountains “CERRO CHASCON” and “CERRO CHAJNANTOR”, white LED shows their positions. The screen installed on the upper left side provides videos of the ALMA Telescope and the ALMA site in Chile.
The MOST COMPACT CONFIGURATION with a minimum layout of the antenna is approximately 150m, while the “MOST EXTENDED CONFIGURATION with a maximum layout of the antenna extends up to 16 km. You can feel the dimensional difference by pressing these two buttons alternately. This miniature model has been reproduced with a reduction scale of 1/10000. This miniature model is as large as 180cm x 180cm, which is designed to be hung on the wall to be fit in a limited space. If space allows, it can be removed from the wall and placed horizontally on the floor with legs for exhibitions in other places.
You can see the miniature model of the ALMA AOS, together with a miniature model of the ALMA 12-m antenna, in the exhibition room at the NAOJ Mitaka Campus.