PREVIEW

If the skies are clear, Brits will be able to spot a revolutionary new NASA spacecraft flying over the length of the country several times this week.

NASA’s Advanced Composite Solar Sail System (ACS3), launched in April, and is testing the use of a massive solar sail to propel spacecraft through space, using only the pressure of sunlight.

Its 9-metre-wide solar sail harnesses the solar wind—much like a sailing boat uses wind—to generate momentum. While this means it accelerates slowly, the lack of resistance in space allows it to build up speed over time.

At the end of August, ACS3 deployed its main solar sail in Earth orbit. The large, reflective sail is visible from the ground when the spacecraft passes overhead at just the right angle to catch the sunlight.

NASA’s ACS3 mission is part of the agency’s efforts to explore new propulsion technologies, which could revolutionise space travel by enabling longer, more cost-effective missions without the need for traditional fuel.

According to satellite tracking service N2YO, the solar sail will be visible in the U.K. on 9 September at 8.46 pm, at 9.28 pm on 10 September, and 9.24 pm on 13 September. On Sunday it will pass at around 9.19 pm.

Those who see the craft will need to be in a dark location, have clear skies, and look North a few minutes before the pass time. If you’re lucky you’ll see a bright ‘shooting star’ moving towards you across the sky.

Rudy Aquilina, project manager of the solar sail mission at NASA Ames, said that the experiment could pave the way for the future of space travel.

“This technology sparks the imagination, reimagining the whole idea of sailing and applying it to space travel,” said Aquilina. “Demonstrating the abilities of solar sails and lightweight, composite booms is the next step in using this technology to inspire future missions.”