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Automated optical meteor fluxes and preliminary results of major showers
| Content Provider | NASA Technical Reports Server (NTRS) |
|---|---|
| Author | Cooke, W. Campbell-Brown, M. Weryk, R. Blaauw, R. Gill, J. Kingery, A. |
| Copyright Year | 2014 |
| Description | NASA's Meteoroid Environment Office (MEO) recently established a twoâstation system to calculate daily automated meteor fluxes in the millimeterâsizeârange for both singleâstation and doubleâstation meteors. The cameras each consist of a 17 mm focal length Schneider lens (f/0.95) on a Watec 902H2 Ultimate CCD video camera, producing a 21.7x15.5 degree field of view. This configuration sees meteors down to a magnitude of +6. This paper outlines the concepts of the system, the hardware and software, and results of 3,000+ orbits from the first 18 months of operations. Video from the cameras are run through ASGARD (All Sky and Guided Automatic Realâtime Detection), which performs the meteor detection/photometry, and invokes MILIG and MORB (Borovicka 1990) codes to determine the trajectory, speed, and orbit of the meteor. A subroutine in ASGARD allows for approximate shower identification in singleâstation detections. The ASGARD output is used in routines to calculate the flux. Before a flux can be calculated, a weather algorithm indicates if sky conditions are clear enough to calculate fluxes, at which point a limiting magnitude algorithm is employed. The limiting stellar magnitude is found using astrometry.net (Lang et al. 2012) to identify stars and translated to the corresponding shower and sporadic limiting meteor magnitude. It is found every 10 minutes and is able to react to quickly changing sky conditions. The extensive testing of these results on the Geminids and Eta Aquariids is shown. The flux involves dividing the number of meteors by the collecting area of the system, over the time interval for which that collecting area is valid. The flux algorithm employed here differs from others currently in use in that it does not make the gross oversimplication of choosing a single height to calculate the collection area of the system. In the MEO system, the volume is broken up into a set of height intervals, with the collecting areas determined by the position of the active shower or sporadic source radiant. The flux per height interval is calculated and summed to obtain the total meteor flux. Both single station and double station fluxes are currently found daily. Geminid fluxes on the peak night in 2012 (12â14â2012) were 0.058 meteors/km2/hr as found with doubleâstation meteors and 0.057 meteors/ km2/hr as found with singleâstation meteors, to a limiting magnitude of +6.5. Both of those numbers are in agreement with the wellâcalibrated fluxes from the Canadian Meteor Orbit Radar. Along with flux algorithms and initial flux results, presented will be results from the first 18 months of operation, covering 3,000+ meteoroid orbits. |
| File Size | 98783 |
| Page Count | 1 |
| File Format | |
| Alternate Webpage(s) | http://archive.org/details/NASA_NTRS_Archive_20140012463 |
| Archival Resource Key | ark:/13960/t26b24r2w |
| Language | English |
| Publisher Date | 2014-06-30 |
| Access Restriction | Open |
| Subject Keyword | Computer Programming And Software Astronomy Subroutines Ccd Cameras Algorithms Meteoroid Concentration Geminid Meteoroids Stellar Magnitude Field of View Detection Photometry Computer Programs Ntrs Nasa Technical Reports Server (ntrs) Nasa Technical Reports Server Aerodynamics Aircraft Aerospace Engineering Aerospace Aeronautic Space Science |
| Content Type | Text |
| Resource Type | Article |
