A solar powered plane, the Solar Impulse, is about to set off on the most challenging leg of its round-the-world flight. The plane began its circumnavigation in March 2015, when it took off from Abu Dhabi. It has since travelled across Turkey and India to China and will soon take off for a five-day, non-stop journey from China across the Pacific to Hawaii. As soon as a suitable ‘weather-window’ is identified, the journey will begin. You can track the journey of the Solar Impulse on their own website or see an interactive map on the website of one of the major sponsors, ABB.