The Desert Fireball Network (DFN) is designed to track meteoroids entering the atmosphere, determine pre-entry orbits, and pinpoint fall positions for recovery by field teams. Beginning in 1959, a dozen projects – professional and amateur – have pursued the goal of recovering meteorites with known orbits. The scientific benefits are significant: detail on how comets and asteroids fragment; their material properties; how their orbits evolve over time. The impact rate of large debris. And with the ability to track meteorites back to their point of origin in the solar system we can derive context information to aid in interpreting meteorite compositions; perhaps even match them with their parent body. However, this combined research effort has yielded 10 rocks. Why so few? All these projects were sited in the temperate zone of the northern hemisphere: vegetated areas where recovery efficiency is marginal. Deserts are one of the few places on Earth where meteorite recovery is straightforward. This was the driver behind the DFN. Two meteorites were recovered during its trial phase (4 film cameras and an area of 150,000km2), proving the concept. Based on that success, digital expansion began in 2012.
Fireball observatories are sited at remote dark-sky sites across Australia - logistics for power, sensor platforms, and data connection are in place. Each observatory is a fully autonomous unit, taking 36MP all-sky images (with fisheye lenses) throughout the night, capable of operating for 12 months in a harsh environment, and storing all imagery collected over that period. The observatories use neural network algorithms to recognize and report fireball events. An automated data reduction pipeline delivers orbital data and meteorite fall positions. The DFN currently has 49 of these observatories across 2.5 million km2 of outback Australia. We successfully recovered a meteorite from Lake Eyre (South Australia) on 31st December 2015, using our automated pipeline, and have now gone forward to reduce our complete fireball dataset, deriving precise orbits for 280 bright fireballs: the largest single dataset of its kind ever collected. We have tracked another 11 meteorite falls to the ground. Searches for these will commence in June, through to October.
Hardware innovations allowed us to turn off-the-shelf cameras into high-end fireball observing stations. Software innovations transformed these units into intelligent imaging systems. Automated data processing, and a supercomputer data management system, allowed manipulation and reduction of large datasets. The advances in hardware, data reduction, and storage that enabled the DFN provide a cost-effective route to an expanded facility. Working with SSERVI colleagues we are exploring the potential for installing new regional and national networks, delivering a large planetary observational facility benefiting multiple users. A combined northern and southern system, with ×5 the current DFN detecting area and data acquisition rate, would observe >300 meteorite falls within 5 years of commissioning.