The Thirty Millimeter Telescope

Abstract

A near-infrared telescope with an effective aperture diameter of 30 mm has been developed. The primary objective of the development is to observe northern bright stars in the J, H, and Ks bands and provide accurate photometric data on those stars. The second objective is to observe a belt-like region along the northern Galactic plane (|b| ≤ 5° and δ ≥ −30°) repeatedly, to monitor bright variable stars there. The telescope has been in use since 2016 December. The purpose of this paper is to describe the design and operational performances of the telescope, the photometric calibration methods, and our scientific goals. We show that the telescope has the ability to provide photometry with an uncertainty of less than $5\%$ for stars brighter than 7, 6.5, and 6 mag in the J, H, and Ks bands, respectively. The repeatability of the photometric measurements for the same star is better than $1\%$ for bright stars. Our observations will provide accurate photometry on bright stars that are lacking in the Two Micron Sky Survey and the Two Micron All-Sky Survey. Repeated observations at a good cadence will also reveal their nature in terms of variability in the near-infrared.