Space InfraRed Telescope Facility

The SIRTF is a 85-cm diameter telescope (Fig. 11) that will be cooled to 5.5 K and specialize in mid- and far infrared observations. Scheduled to be launched on a Delta rocket in December of 2001, SIRTF will provide an excellent follow-up on the ISO observations and offer unique areas of science of its own. At this time SIRTF is expected to provide a significant increase in sensitivity and field of view over ISO, primarily due to an improved detector complement. The SIRTF orbit is a unique earth-trailing heliocentric orbit that will place the spacecraft at a considerable distance from Earth. This will facilitate the cooling of the telescope, which will be launched warm and then cooled once the proper orbital position is achieved. SIRTF contains three focal plane instruments described below. 

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FIGURE 11 Configuration of the Space InfraRed Telescope Facility spaceaaft. 

The HST can also observe in all regions of the IR, but its optics and stmetures are not cooled to minimize radiation emission, and its images are diffraction limited at IR wavelengths. In the late 1990s, NASA launched the Space Infrared Telescope Facility, a 1-m class telescope that operates inside an enclosure cooled by liquid helium to avoid the excess radiation problem. 

Abstract. This paper describes the status of NASA s Space Infrared Telescope Facility (SIRTF) program. SIRTF will be a cryogenicaily cooled observatory for infrared astronomy from space and is planned for launch early in t next decade. It will be the first cryogenic space observatory to make extensive use of the powerfrd infrared detector array tednology discussed at this conference. We summarise a newly developed SIRTF mission concept and show how the availability of detector arrays has shaped the scientific rationale for SIRTF, and how the arrays themsdves have become part of the definition of the SIRTF misaon. 

Two 256X256-pixel arsenic-doped-silicon (Si As) impurity band conduction (IBC) hybrid detector arrays developed by Hughes Technology Center have been evaluated for space-based astronomy applications. Potential applications include instrumentation on orbiting astronomy platforms such as the Space Infrared Telescope Facility (SIRTF). 

The Space Infrared Telescope Facility (SIRTF) is our first opportunity to use hi performance infrared arrays on a cooled telescope, where they can reach sensitivity leveb determined only by the environment of the earth in space - that is, by emissions from the zodiacal doud, the Milky Way, or distant galaxies. From space, we are no longer restricted in spectral coverage. To increase the power of SIRTF and to provide a reasonable match of capabilities across its operating range, the MIPS (Multiband Imaging Photometer for SIRTF) team has imdertaken the development of far infrared arrays. This effort has produced the first high performance far infrared photoconductor array evex built. 

The t3q>ical approach taken for astronomical applications is that of a detector integrator source follower. This was used in the Space Lxfrared Telescope Facility (SIBTF) designs[l] as well as the designs used for the proposed Hubble Space Telescope infrared refurbishment instruments[2]. That same approsudi is also utilized here, with particular customizations for this specific application. The detector array utilizes a newly developed detector process enhancement which offers some significant advantages in performance. 

Visiting Astronomei at the Infrared Telescope Facility, which is operated by the University of Hawai i under contract with the National Aeronautics and Space Administration. 

The European Space Agency is currently studying the feasibility of an infrared telescope of about 3 m diameter for Spacelab. Provision of such a facility would offer enormous advantages over existing aircraft and balloon-borne systems for detailed studies of astronomical sources in the far infrared. 

Herschel (formerly known as FIRST, Far InfraRed and Sub-millimetre Telescope) was successfully launched on 14 May 2009 by ESA. The telescope was named after Sir W. Herschel who proved the existence of IR radiation. Herschel carries a 3.5 meter diameter passively cooled telescope. Herschel (Fig. 9.8, see also Doyle, Pilbratt, and Tauber, 2009, [111]) is the only space facility dedicated to the submillimeter and far infrared part of the spectrum (55 to 672 pm range). The main tasks of Herschel are ... 

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