We report high resolution multi-station observations of meteors by the Canadian Automated Meteor Observatory (CAMO) recorded from June 2009 to August 2010. Our survey has a limiting detection magnitude of +5 mag in R-band, equivalent to a limiting meteoroid mass of ∼ 2×10 −7 kg. The high metric trajectory accuracy (of the order of 30 m perpendicular to the solution and 200 m along-track) allows us to determine velocities with average uncertainty of < 1.5% in speed and ∼0.4 • in radiant direction. A total of 1739 meteors had measured orbits. The data has been searched for meteors in hyperbolic orbits, which are potentially of interstellar origin. We found 22 potential hyperbolic meteors among our sample, with only two of them having a speed at least three sigma above the hyperbolic limit. For our one year survey we find no clear evidence of interstellar meteoroids at mm-sizes in a weighted time-area product of ∼10 4 km 2 h. Backward integrations performed for these 22 potentially hyperbolic meteors to check for close encounters with planets show no considerable changes in their orbits. Detailed examination leads us to conclude that our few identified events are most likely the result of measurement error. We find an upper limit of f ISP < 2×10 −4 km −2 h −1 for the flux of interstellar meteoroids at Earth with a limiting mass of m > 2 × 10 −7 kg.

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During the preceding years, the Astronomical Institute of the University of Bern (AIUB) was conducting several search campaigns for space debris in the geostationary ring (GEO). The optical observations were performed with a 1-m Ritchey-Chr etien telescope on Tenerife. A substantial population of unknown, small-sized objects was found in these surveys. For all objects a circular orbit was determined using the discovery observations. In order to test the hypothesis of circular orbits -which most likely is not valid for all detected objects -it is necessary to determine eccentricities for at least a part of the population. This in turn requires follow-up observations of the detected objects. The improved orbits resulting from follow-up observations also increase the probability for a successful recovery of the object in subsequent nights. Eventually, follow-up observations over several nights yield ''secure'' orbits allowing to build up a catalogue. In this paper we present the results of the determination of circular orbits and the orbit improvement process yielding elliptical orbits. The accuracy of the determined orbits is discussed, and the orbit quality is tested with follow-up observations after a few nights. The orbital elements are compared with those based on the assumption of circular orbits.