Stellar Calibration of the Smart Panoramic Optical Sensor Head (SPOSH)

The SPOSH camera is designed for observations of transient phenomena on the night hemisphere of Earth (or other planets) from an orbiting spacecraft. It is currently being tested during observation campaigns for meteors from ground. The camera features a highly sensitive (1024 x 1024) CCD chip, a wide (>120°) field of view, is typically operated at a high rate (2 frames / sec) and has sophisticated built-in software for event detections and reporting. To calculate celestial positions and trajectories for recorded meteors it is necessary to determine the parameters for the inner and exterior orientation of the camera. Our camera model includes three orientation angles w, f, k, the focal length, the coordinates of the principal point and a second order polynomial describing the radial distortion. The model parameters are determined by stellar calibration using images of star fields recorded during recent meteor campaigns. Star positions in the images are determined from the maxima of Gauss functions fitted to the observed pixel patterns. The use of stars with their precisely known positions taken from a star catalog warrants high calibration accuracy. In recent tests we identified approximately 5.000 stars in a single image, more than 1700 of which could be related to catalog entries. After the analysis, the residual error of star positions is on average 0.25 pixels. The calibration software is developed under IDL (Interactive Data Language) and is intended to be user-friendly for less experienced users

Space Surveillance Network Capabilities Evaluation Mission

The last years saw the diffusion of nano, pico and femto satellite missions launched by multiple entities thanks to the launch cost reduction and the electronics miniaturization. Such missions usually present limited capabilities in terms of precise orbit determination and extremely small radar and optical cross-sections. Often these missions carry one or more laser retro-reflectors for precise orbit determination but precise orbital measurements cannot be found in the literature. Miniaturized GNSS receivers are also often carried out but due to the experimental nature of such missions, the reliability and time span of such measurements is limited, leaving radar tracking as the only reliable tracking method. Due to the size of such satellites, the signal-to-noise ratio of such radar measurements is typically low and satellite identification (when launched on ride-share launches with a hundred or more other satellites) proves difficult and time-consuming.Being these very small satellites at the edge of the radar detection capabilities and not providing independent orbit determination means, their position uncertainty could be quite significant, leading to an increased orbit collision perceived risk.With this paper, we present a dedicated small satellite formation, made by multiple nano and pico satellites to evaluate the space surveillance network tracking capabilities and limits. The formation is made by a 3U CubeSat to be deployed as part of a rideshare launch. The satellite would be equipped with multiple means to track it, including a GNSS receiver, a set of multiple laser retro-reflectors, and LEDs for optical, laser, and radar tracking, allowing to characterize also different detection means in terms of capabilities. Such a satellite is made of two independent smaller satellites that can be un-docked in orbit upon command, reducing the satellite size and cross-section. This would push the detection limit for the space surveillance networks starting from an already acquired object and with limited clutter around it. Independent laser and GNSS tracking would allow ground measurement validation and validate position estimations. Further pico-satellites would be deployed by each sub-satellite to further push the detection limits and validate up to which size objects are trackable (still optically, radar and GNSS), thanks to miniaturized GNSS receivers already flown by several other missions.Sub-satellite separation is implemented upon command to ensure the process can be followed and executed at lower altitudes to limit the orbital lifetime of eventually hard-to-track small objects that could worsen the space debris problem. Ground characterization (in terms of optical and radar properties) will be performed, also including polarimetric measurements used to identify the separate satellites. All these technologies together would contribute to creating a unique tool to estimate the tracking capabilities of multiple instruments, specifically tailored for very small objects, the hardest to track, as compared to other characterization activities performed on much bigger objects

Observations of the Perseids 2015 using the SPOSH cameras

We will organize a meteor campaign in Greece focusing on the observation of the meteor activity during this year’s maximum of the Perseids meteor shower. Double-station observations will be carried out from 10th until 14th of August using SPOSH cameras. During this period, we anticipate rates up to 100 Perseids per hour. The participation of graduate students during the observations and the data reduction will strengthen the educational aspect of the campaign

The High Resolution Stereo Camera (HRSC) - Digital 3D-Image Acquisition, Photogrammetric Processing and Data Evaluation

Digital techniques replaced more and more the analogue photogrammetric analysis in daily work during the past years. The consequent way to complete the digital line is to per-form digital data acquisition. Since digital frame cameras for photogrammetric purposes will not be available within the next years, digital line scanners can fill this gap. At the Institute of Planetary Exploration of the German Aerospace Center (DLR) the High Resolution Stereo Camera (HRSC) has been designed for international missions to planet Mars. During the past two years an airborne version of this camera, the HRSC-A, has been successfully applied in many flight campaigns and in a variety of different applications. The HRSC-A fulfils all requirements of a photogrammetric sensor. It is based on the along-track triple-stereo principle even using 9 CCD arrays and combines 3D-capabilities and high resolution with multispectral data acquisition. Variable resolu-tions depending on the camera control settings can be generated. A high-end GPS/INS system in combination with the multi-angle image information yields precise and high-frequent orientation data for the acquired image lines. In order to handle these data a completely automated photogrammetric processing system has been developed in cooperation between the Department for Photo-grammetry and Cartography of the Technical University of Berlin and the DLR. This system is capable to generate impressive multispectral 3D-image products of the HRSC-A data combined with accuracies in planimetry and height of better than 0.1 thousandth of the flight altitude, accuracies which have been confirmed by detailed investigations

The High Resolution Stereo Camera (hrsc) - Digital 3d-Image Acquisition, Photogrammetric Processing And Data Evaluation

Digital techniques replaced more and more the analogue photogrammetric analysis in daily work during the past years. The consequent way to complete the digital line is to perform digital data acquisition. Since digital frame cameras for photogrammetric purposes will not be available within the next years, digital line scanners can fill this gap. At the Institute of Planetary Exploration of the German Aerospace Center (DLR) the High Resolution Stereo Camera (HRSC) has been designed for international missions to planet Mars. During the past two years an airborne version of this camera, the HRSC-A, has been successfully applied in many flight campaigns and in a variety of different applications. The HRSC-A fulfils all requirements of a photogrammetric sensor. It is based on the along-track triple-stereo principle even using 9 CCD arrays and combines 3D-capabilities and high resolution with multispectral data acquisition. Variable resolutions depending on the camera control settings can be..