The UK Desert Fireball Network: Continuation

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The Desert Fireball Network has already been an extremely successful facility. However, to fully exploit the science potential of this system (see 'Objectives'), it is necessary to go beyond the trial network that we currently have, and build towards a fully operational fireball network covering a large area (>1 million km^2). To summarise our current achievements: We have designed, built, and field-tested an autonomous fireball observatory. We deployed a small trial network of these units in the Western Australian Nullarbor, and showed that they could withstand desert conditions for extended periods. We demonstrated that our imaging system, when integrated to provide networked observations of fireballs, could deliver some of the most precise orbital data ever recovered from fireballs. We determined the first orbits for southern hemisphere fireballs. We determined fall positions for objects with a significant terminal mass. We recovered a meteorite on the first day, of the first search: the first fragment was found 97m south from the predicted central fall line; the second fragment was recovered 39m north from the central line shortly after. In summary, we have demonstrated that we have the technology, logistics, and methodology to address research questions of fundamental importance, and acquire a unique sample set. The last remaining milestone was to prove that we could recover meteorites on the ground. The fact that we found meteorites within 100m of their predicted fall positions indicates that our combination of standard computation of meteoroid 'darkflight' and high resolution modelling of winds in the upper atmosphere (see main case) is an extremely powerful tool. In short, we have met all our near-term goals. It is now time to move beyond a preliminary network, so that we can fully address the central research objectives. We currently have four observatories (two of which are STFC funded). This trial network has been in operation for only around 2.5 years. Although the small number of observatories makes it vulnerable to single-point failure (loss of one camera can result in suspension of networked observations), our success with the DFN (we are orders-of-magnitude more productive than previous fireball networks - see main case) indicates that an expanded network will be capable of delivering dozens of meteorites over the lifetime of the project. The proposed work will allow us to begin that expansion.