Laser Bees Update
Posted by Bruce Betts
29-10-2013 17:42 CDT
Below is an update from Alison Gibbings and Massimiliano Vasile of the University of Strathclyde in Scotland about the Planetary Society supported Laser Bees asteroid deflection project. The Laser Bees concept would use a small “swarm” of spacecraft, each equipped with a powerful laser, to change the orbit of a potentially dangerous asteroid if one threatened the Earth. The lasers would vaporize (ablate) rock on the surface of the asteroid over weeks, months, or years and that would create jets of material that would push the asteroid in the opposite direction. The technique seems very promising in theory, but the Planetary Society sponsored laboratory Laser Bees project is designed to better understand various aspects of this seemingly promising technique.
The Laser Bees team have been literally zapping rocks with lasers and making holes in the rocks while measuring the results. Now, they have acquired some new hardware (thanks to Planetary Society members and donors) to take the investigation to the next level, as they discuss below. They discuss not only their recent progress, their recent hardware acquisitions and planned work using that hardware (please support that future work), and awards they have been winning, but also discuss interesting projects that have grown, in part, out of our Laser Bees supported effort, including the large Stardust program sponsored by the European commission. We are very happy that not only is progress being made on Laser Bees, but that our support of that project, in part, has led to other near Earth asteroid related projects. Here is what Alison and Massimiliano had to say:
The last few months have been a busy time for us. With the support of The Planetary Society, we have been able to continue the development of our laser ablation experiments. Thanks to the Planetary Society we now have a new 130W fibre laser, an improved vacuum chamber, new diagnostic tools and new samples made of asteroid analogous material, plus some meteorites. Our new experiment campaign will examine, using new measurements (in-situ mass balance, high speed camera and a thermal camera), the potential of laser ablation for the exploration, exploitation and deflection of asteroids. It will enable us to measure the initial expansion and development of the gas and ejecta plume, and further improve the mathematical model to predict the thrust magnitude. We now have a better understanding of the physics behind the ablation of asteroids and in particular the energy losses that can reduce the efficiency of the ablation process. At the same time, we understood that, compared to other deflection systems based on low-thrust propulsion systems, efficiency is not a concern as the mass required to deflect the asteroid comes from the asteroid itself.
We have also been busy publishing our results. Results were recently presented at the 2013 IAA International Planetary Defence Conference, Flagstaff, USA and we were awarded second prize in the student paper competition. This was a great surprise as we had won first and second prize at the previous 2011 Planetary Deference Conference in Bucharest, Romania. This builds upon a string of successes that includes winning the Institute of Mechanical Engineering Speak out for Engineering award, and more impressively, the Institute of Mechanical Engineers Postgraduate Scholarship for Outstanding Researcher of 2013.
The results gathered from the work supported by the Planetary Society allowed us to push the boundaries of the research on asteroid deflection and to initiate larger research projects. For example, the results gained from the experiments were instrumental to develop a mission study, supported by ESA, on a small technology demonstrator that could be used to test laser ablation on a small scale asteroid. The Light Touch2 mission study, supported by the SYSNova initiative of the European Space Agency, demonstrated that with a relatively small laser system, 540-860W, on board a small 1 ton spacecraft, one can effectively modify the orbit and the rotation motion of a small 4m diameter asteroid, in 8 months. The particular asteroid we selected is in fact so close to the Earth that such a small modification could lead to a capture.
The results coming from the work supported by the Planetary Society allowed us to initiate a large 4 year programme of research supported by the European Commission and called Stardust (twitter: @stardust2013eu). The overriding goal of Stardust is to train researchers to develop and master techniques for asteroid and space debris monitoring, removal/deflection and exploitation such that they can be applied in a real scenario. It is our belief that the integration of all the disciplines involved in Stardust is a fundamental step towards the resolution of the asteroid and space debris issue and has beneficial consequences in all research areas. The scientific program focuses on a number of underpinning areas of research and development that are fundamental to any future and present initiative aiming at mitigating the threat posed by asteroids and space debris, and is divided into three major research areas: Modelling and Simulation, Orbit and Attitude Estimation and Prediction, and Active Removal/Deflection of Uncooperative Targets.