41 research outputs found
Characterisation of Fragmentation Clouds and Fragmentation Event Reconstruction for Space Break-Up Forensics
On-Orbit Breakup Forensics: Analysis of Measurement Data to Reconstruct Fragmentation Events in Space
DC bias immune nanocrystalline magnetic cores made of Fe73Nb3Cu1B7Si16 ribbon with induced transverse magnetic anisotropy
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
Concrete repair with ultra ductile micro-mesh reinforced abrasive resistant and impervious mortar
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
