After 20 years, NASA engineers recently finished building the largest and most powerful space-bound telescope ever made. The James Webb Space Telescope will travel 1.6 million kilometers (1 million miles) from Earth to study faraway stars.
NASA plans to launch the telescope in October 2018. From space, the telescope will watch the sky with 18 gold-plated mirrors and four special cameras. They collect infrared radiation (IN-fruh-red ray-dee-AY-shun), a type of light invisible to the human eye. It’s given off by stars and other objects in space.
Why focus on infrared? Dust clouds in space block visible light. But infrared waves travel through them. Collecting this radiation will give the telescope a clearer view. “It’s going to see galaxies and stars farther away than we’ve ever been able to see before,” says NASA scientist Hannah Wakeford.