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The Deep Impact (DI) spacecraft encountered Comet 9P/Tempel 1 on July 4th, 2005 and observed it with several instruments. In particular, we obtained infrared spectra of the nucleus with the HRI-IR spectrometer in the wavelength range of 1.0–4.9 μm. The data were taken before impact, with a maximum resolution of ∼120 m per pixel at the time of observation. From these spectra, we derived the first directly observed temperature map of a comet nucleus. The surface temperature varied from 272 ± 7 to 336 ± 7 K on the sunlit hemisphere, matching the surface topography and incidence angle. The derived thermal inertia is low, most probably

This paper discusses the development of two materials as AR coatings for thinned backilluminated charge-coupled devices. The first material is the heavy metal oxide Ta205 deposited as a spin on layer using sol-gel technology. The second material is Si3N4. Both these films have the high index of refraction and low absorption coefficients needed to produce good AR coatings in the near UV down to 300 nm. The goal of the program was to produce a coating which would yield devices with quantum efficiencies of greater than 50 at 300 nm. Both these materials satisfy this goal. Data on test devices will be reported. . 1.© (1992) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

The development of the 20482 CCD for a second generation Space Telescope instrument has resulted devices with very few defects dark currents of less than 12 electrons/pixel/hour at 80 readout noise levels of less than 4 electrons rms and excellent charge transfer efficiency at signal levels of less than 10 electrons. A second generation of devices that capitalize on these characteristics have been produced and are currently in test. Faster frame transfer devices that preserve these characteristics have been designed that include tn-directional taps in the serial register. 1.© (1992) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

The Giotto Halley Multicolour Camera obtained images of P/Halley that resolved the nucleus, showing active regions and other features on the surface. At least twenty-one discrete bright features can be identified in the images, and eight distinct regions associated with morphological characteristics can be recognized. The projected limb is approximated with a two-to-one axial ratio ellipse, establishing a reference coordinate system for the body based on the center of gravity and moments of inertia of the profile. A catalog of surface features is presented giving size, shape and location in the reference coordinate system.

The four quadrant CCD was developed to meet the reliability needs of future space programs that use large area CCDs. The 1024 2 format was selected as a precursor to the 2048 2 format. An experimental lot of 1024 2 CCDs was made in 1987 and a production lot was run in 1988 for the AXAF star tracker program. Excellent performance was obtained with the production lot and the four quadrant operation was demonstrated to work as predicted.

A novel sounding rocket payload consisting of a slitless objective grating spectrograph with no transmission elements in the optical train (or detector) is described. This instrument, called the interstellar medium absorption profile spectrograph (IMAPS), is designed to provide continuous coverage over the wavelength range of 950-1150 A; it has an effective collecting area of about 4 sq cm and can record spectra of pointlike sources at a wavelength resolution of 0.004 A and with a sample interval of 0.002 A. The successful use of this instrument aboard a Black Brant rocket is described.

A novel design for a high-resolution imaging system which includes on-board data editing and optical navigation, suggests high quality images can be acquired from spin-stabilized spacecraft oriented towards high velocity, short duration planetary missions ("Probes"). The approach to designing imaging systems requires that mission objectives be met within the physical and fiscal constraints imposed by the spacecraft and mission design. Severe constraints imposed on a Comet Halley probe (for example, 57km/sec encounter velocity with a small, 10km diameter, object coupled with a great uncertainty in encounter time and distance, were overcome by innovative use of existing technology. Such designs suggest that 3-axis stabilization or non-spinning platforms are not necessary to acquire high resolution, high quality planetary images.© (1981) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

A partially- inverted mode of operation of the Tektronix 10242, 3 -phase CCD has been tested and characterized.In this mode, two of the three parallel phases are held in the inverted mode during integration while the third isheld in the non -inverted mode. This mode offers a compromise between the low dark current and low full wellcapacity of fully inverted operation, and the high full well and high dark current of non -inverted operation. 1. INTRODUCTION The Center for Solid State Imaging at Ball Aerospace is a research facility designed to test and characterizeCCD performance for various scientific applications. The Tektronix series of large format, high resolution [1] CCDimagers are presently being tested with the most emphasis being placed on the 10242, 3- phase, four -quadrantreadout devices. These devices are mounted in a liquid nitrogen cooled dewar camera system which is mounted toan optical bench. This system has the flexibility to drive virtually any CCD and parameters such as integrationtime, clock frequency, clock voltages, bias voltages, system gain, and device temperature are easily controlled.One of the most important parameters that affects CCD camera systems built for wide dynamic range perfor-mance is the dark current. Dark current arises from thermally generated carriers within the CCD, rather than thedesirable ones produced by incident photons from the image. The dark current contribution for long exposures atlow light levels, common in astronomy and other scientific applications, can have a significant effect on the qualityof the image if the dark current represents a large fraction of the output signal. To reduce the dark current to tol-erable levels, some method of cooling the device is generally required. Sophisticated and costly liquified gas dewarsare the most common methods of cooling CCD's where a large temperature differential or a very low temperatureis required. Thermoelectric coolers can be used where smaller temperature differentials are acceptable, however,this too adds cost and complexity to the overall system design.

A persistent image-converter device was utilized to make visible to the astronaut solar images that were isolated, instantaneous flashes on the ATM TV monitors. In addition, these instantaneous images, as well as normal TV images, were recorded with a Polaroid SX-70 camera for study by the astronauts.