Final thrust puts SMART-1 on course for lunar encounter
The European Space Agency (ESA) Moon orbiter, SMART-1, is now on the final leg of its journey, having already covered more than 80 million kilometres. From 10 to 14 October, the experimental solar-powered ion engine onboard SMART-1 carried out a continuous thrust manoeuvre designed to deliver the spacecraft to the Moon capture point on 13 November. Since its launch on 27 September 2003, the craft has been spiralling in progressively larger orbits around the Earth with the aim of eventually being captured by lunar gravity. All that remains of SMART-1's 13-month voyage is two more orbits around the Earth before it falls into the natural sphere of lunar attraction and begins to orbit the Moon. The spacecraft's lunar orbit will become progressively smaller and smaller until it reaches its final operational orbit of between 300 and 3,000 kilometres. Then, for the following six months SMART-1 will begin a comprehensive survey of the key chemical elements on the lunar surface, and will investigate the theory of how the Moon was formed.