Detection strategy
The acquisition and detection software FreeTure was specifically developed by the FRIPON team and runs permanently on the minicomputers. The images corresponding to single detections by FreeTure are stored locally and a warning (time and location) is sent to the central server in Marseille. If at least one other station detects an event within +/-3 s, it is then treated as a “multiple detection”. Note that we implemented a distance criterion of less than 190 km to avoid false detections.
Radio data corresponding to the last week of acquisition are only stored locally. Only radio data acquired at the time of an optical multi-detection are uploaded from the radio stations to the Marseille data center for processing.
Data storage and access
The FRIPON stations are composed of a Linux minicomputer, a wide-angle camera, and a manageable switch guaranteeing the isolation of the network of the host institute. The installation is done with an automated deployment system based on a USB key.
When connecting to the host, the station establishes a secure VPN tunnel to the central server of the FRIPON project hosted by the information technology department of the OSU Institut Pythéas (SIP) for all cameras and partner networks worldwide.
The minicomputer is used for the acquisition and temporary storage of long exposure captures, and detections through the FreeTure open source software and a set of scripts. The data, which include astrometric long exposures images, single detection (stacked images), and multiple detections (both optical and radio raw data) are subsequently transferred to the central server.
The data collected on the server are then indexed in a database. During this operation, visuals are generated. When an optical event groups at least two stations, the FRIPON pipeline is executed to generate the dynamical and physical properties of the incoming meteoroid such as its orbit, its mass and its impact zone.
All the data are made available through a web interface that is accessible to the worldwide community in real time. The interface makes it possible to display and download data in the form of an archive that complies with the data policy of the project by means of access right management.