A note for younger viewers: In Chapter 3: People, which features the story of Jasmine Akhter, a garment worker in Bangladesh, there are graphic scenes of the Rana Plaza factory building collapse from 3m10s to 3m52s.
In the year 2020, seven of the largest mirrors on Earth — 20 tons each — will come together in a 22-story, rotating building located in the southern Atacama Desert of Chile. They will form the Giant Magellan Telescope, a feat of science, technology, engineering and math that will have ten times the resolution of the Hubble Space Telescope.
In this video from July 2013, Dr. Wendy Freedman, Chairman GMT, and Dr. Pat McCarthy, Director GMT, explain the astounding challenge of creating this precise, powerful, and wondrous machine. Read more at Phys.org.
Melting down and recycling existing steel products is a more efficient and sustainable process than mining iron ore to make virgin steel. From the EPA:
Recovering steel not only saves money, but also dramatically reduces energy consumption, compared to making steel from virgin materials. In turn, this reduces the amount of greenhouse gases released in to the air during processing and manufacturing steel from virgin ore.