The Japanese satellite-borne infrared telescope, the Infrared Telescope in Space (IRTS), surveyed about 7 per-cent of the entire sky in the infrared wavelengths from 1.4 to 700 μm. The IRTS consists of a 15 cm telescope cooled with superfluid liquid helium, and is installed on board the Space Flyer Unit (SFU) spacecraft. The SFU was launched on 1995 March 18 UT. The sky survey by the IRTS started on March 29 UT, and was completed on April 25 UT after exhausting its liquid helium. The four focal-plane instruments were on board.
The Near-Infrared Spectrometer (NIRS) covered 1.4 to 4.0 μm by 24 spectral channels with the resolution of Δλ = 0.13 μm. The complete level of the catalog is 10?20 Jy for the entire wavelength range. The NIRS point source catalog contains spectra of 14,223 sources in which 4,002 sources are in good quality. Late-type stars, normal stars, and other red objects are included.
