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The CARSO laboratory has recently built a calibration bench for electro-optical qualification of CCD sensors. For the CCD characterization the following measurements are operative: linearity, quantum efficiency, charge transfer efficiency, photon-transfer curve, dark charge and pixel-to-pixel sensitivity nonuniformity. The optical system is essentially made of two different optical paths: the first produces a spot of a few microns diameter, the second gives a uniform beam. For a 98% uniformity illumination, an integrating sphere is also available. There is a choice of two lamps, tungsten and xenon, to illuminate the optical path. The CCD sensor is positioned on a three axis assembly which can be displaced with a resolution of 1 μm on three degrees of freedom. It is set into a thermo-cryostatic vacuum chamber that can maintain the temperature between −140 and +80°C with a stability better than 0.1°C. The bench permits a quasi-automatic control of the various components and interfaces different types of CCDs of different sizes (up to 2048×2048 pixels). Some results of characterization measurements of a Thomson TH7863 CCD are presented.

Four different thermal-vacuum tests were performed on AMICA Star Tracker (AST) in the period March-July 2006 in the space simulator of the SERMS laboratory in TerniItaly. Each of these tests was designed to verify different AST camera design features. The Thermal Balance test was conceived to validate the thermo-elastic model of the instrument and the active and passive thermal control subsystems. The Thermal Vacuum Cycling test was conceived to validate the AST electronics operative and survival temperature limits under vacuum conditions. The worst hot and cold operative and survival limits of the lens and filters in the AST optical system were assessed by means of the “Sun in the lens” and Lens Cold tests.

SD2000 is a new photon counting MCP based detector. It consists of a single MCP, coated with a suitable photocathode, closely coupled to a Silicon Drift Detector (SDD). The electron clouds generated by the MCP channels are accelerated by a strong electric field applied and proximity focussed on the SDD, that works as a position sensitive read-out detector. The SDD, developed by the INFN laboratories in Trieste, is a butterfly Silicon Drift Detector with no metal deposition on its cathodes. The absence of metallization in the sensitive zone of the chamber allows the electron clouds to penetrate uniformly into the active region of the detector and to be revealed. A suitable front-end amplifier, that works as a charge preamplifier and a bipolar shaper, has been developed starting from SPICE simulations and tested. A proto-type of the detector has been realized and tested and the first results have been achieved and compared with the expected best performances of the detector.

The characteristics of the fine pointing and tracking system of UVISS, UltraViolet Italian Space Surveyor, which is proposed to fly as an external payload attached to the ISS (International Space Station) Express Pallet is presented. The system is derived from the pointing system of the UVSTAR telescope that has flown three times on the Shuttle. The electro-optical architecture of the tracking telescope, including the ICCD detector and the computational unit based on a DSP board with direct high speed interface to the camera and the on-board stellar catalog is described. The simulations performed to determine the instrument expected tracking precision and performances considering the dynamics of the ISS are reported. Finally the utilization of a high frequency tracking error correction based on the detection of the spectrographs zero-th order signal is considered as an independent tracking error measurement which provides information and corrections of possible residual tracking errors and could be used for alignment check as well.

A Mission into Hot Phenomena in the Universe is proposed by means of a small telescope of 50 cm aperture accommodated on the International Space Station. Two operating modes are envisaged: 3 angstrom dispersion imaging spectroscopy in the 90 - 320 nm range (1st priority) or wide field (1 degree) medium bandwidth imaging in the same range but Ly-(alpha) (2nd priority). It will use a pointing platform attached to an Express Pallet Adapter available to the Italian Space Agency (ASI) more than 4 - 6 months per year. During a life time of 6 yr focal plane instruments may be changed when on-ground refurbishment occurs. With reasonable exposure times hot thermal sources as faint as V equals 19 - 2 can be observed in the spectroscopy mode at 110 nm and active chromospheres on cool stars as faint as V equals 15 at 250 nm can be monitored. Assessment of FUV imaging is underway, possibly providing observations of hot sources as faint as V equals 21 - 22. Nominal uplift to ISS is set in Autumn 2005.© (2000) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

We present the characteristics of a star mapper, AMICA, which could be used for determining the pointing direction of external payloads mounted on the International Space Station. AMICA, which is complementary to the GPS attitude determination system provided by the ISS, is a stand alone system able to provide both the pointing direction in the inertial reference frame with arc-sec precision at a 1 Hz rate and the angular orientation of the stellar field with slightly lower precision. The star mapper is derived from the pointing system of the UVSTAR telescope that has flown three times on the Shuttle. We present a description of the AMICA optical and electronics architecture and its functionality. We also give a summary of the key pointing/tracking results obtained during the Shuttle missions. Finally we report on simulations performed to determine the instrument expected precision and performances, including the percentage of recognized stellar fields. AMICA is presently considered for flying in support ...

Software for star field identification and star pointing and tracking is described. The software will be implemented in the guiding system of UVSTAR, a spectrograph/telescope system for UV astronomy and planetary physics that will operate as a Hitchhiker payload on the Shuttle. The software work with the wide-field CCD camera and an on-board stellar catalog. It is capable of (1) providing high accuracy (better than 2 arcsec) attitude determination from coarse (± 3 deg) initial knowledge of the pointing direction and (2) pointing toward the target. It is capable of tracking at the same high accuracy with a processing time of less than a few hundredths of a second. Simulation of observations and various types of tests are also discussed.