IRTS Instruments
The Infrared Telescope in Space (IRTS) is a cryogenically cooled small infrared telescope that will fly aboard the small space platform Space Flyer Unit. It will survey approximately 10% of the sky with a relatively wide beam during its 20 day mission. Four focal-plane instruments will make simultaneous observations of the sky at wavelengths ranging from 1 to 1000 microns. The IRTS will provide significant information on cosmology, interstellar matter, late-type stars, and interplanetary dust. This paper describes the instrumentation and mission.
Characteristics of the IRTS
| Weight | Total Weight : 183 kg |
| Cryostat : 128 kg | |
| FPI+telescope : 9 kg | |
| Electronics : 16 kg | |
| Support structure : 18 kg | |
| Others : 12 kg | |
| Dimensions | 93cm diameter (cryostat) x 135 cm (including aperture shade) |
| Power consumption | 80 W maximum |
| Cryostat | Superfluid helium, 90 liters |
| FPI temperature : 1.9 K | |
| Cold lifetime : > 35 days after launch | |
| Telescope | 15 cm diameter F/4 Richey-Chretien type |
| Effective collecting area : 113 cm2 | |
| FPIs | Near-Infrared Spectrometer (NIRS) |
| Mid-Infrared Spectrometer (MIRS) | |
| Far-Infrared Line Mapper (FILM) | |
| Far-Infrared Photometer (FIRP) | |
| Telemetry | Data rate : 6 kbits/s (visible orbit), 3 kbits/s (invisible orbit) |
| Observation | 20 days, uniform sky survey |
| Sky coverage | Approximately 10% of the entire sky |
Cross Section of IRTS
Telescope & FPI of the IRTS (Provided by ISAS.)
FPIs of the IRTS
Four scientific instruments, the Near-Infrared Spectrometer (NIRS), the Mid-Infrared Spectrometer (MIRS), the Far-Infrared Line Mapper (FILM), and the Far-Infrared Photometer (FIRP) are installed in the focal plane of the telescope together with a near-IR sar sensor.
For more details, refer to the following publications.
- "The Infrared Telescope in Space (IRTS)"
-
H. Murakami, J. Bock, M. M. Freund, H. Guo, T. Hirao, A. E. Lange, H. Matsuhara, T. Matsumoto, S. Matsuura, T. J. McMahorn,
M. Murakami, T. Nakagawa, M. Noda,K. Noguchi, H. Okuda, K. Okumura, T. Onaka, T. L. Roellig, S. Sato, H. Shibai, T. Tanabe,
T. Watabe, T. Yagi, N. Yajima, and M. Yui
1994, The Astrophysical Journal, vol.428, p.354-362 - "IRTS Mission"
-
T. Matsumoto
1996, in SPIE Proc.2817, Infrared Spaceborne Remote Sensing IV ed. M. S. Scholl and B. F. Andresen, p.238-247 - "Flight performance of the Infrared Telescope in Space (IRTS)"
-
Hiroshi Murakami, Hiroshi Shibai, Takashi Onaka, and Takanori Hirao
1996, in SPIE Proc. 2744, Infrared Technology and Applications XXII ed. B. F. Anderesen and M. S. Scholl, P.68-74