Great Solar Shield

The Great Solar Shield was a space station built in the 21st century. It was created by the humans to float in orbit of Earth. It consisted of a network of prismatic mirrors that would block out the sunlight reaching the planet, creating a partial eclipse for the planet in order to reduce global warming. The crew were not to return to Earth. However, the space station came under attack by the Silhouettes, who were searching for energy to feed on. They descended on Earth, but the Doctor aligned the prismatic mirrors with the sunlight, splitting it into different wavelengths and creating a rainbow, that scared the Silhouettes away. The space station disintegrated, but the Doctor told Martha that the human race would eventually find another solution for the global warming problems. (DWS: Sunscreen)