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There is an ongoing debate within the transportation analysis community over whether automated vehicles will reduce energy use and greenhouse gas emissions, or increase them. On the one hand, automated vehicles can both drive more efficiently and be designed to be lighter, saving energy. However, the convenience of not having to pay attention on the road may lead people to use them more, increasing energy consumption. Which effect will tend to prevail?

While NASA is planning to send the first human explorers to Mars sometime in the 2030s, several non-governmental organizations, including at least one private company (SpaceX), are looking at more aggressive timelines starting in the 2020s. They are also setting a higher bar: rather than sending astronauts for a limited-duration mission, the goal is establishing a permanent human settlement.

A commercial space transportation industry is growing rapidly. Private companies are competing for launch contracts for government, military and private customers, and prices are falling quickly. NASA is turning its human spaceflight attention from low Earth orbit to the Moon and beyond. Several companies are even thinking about building settlements on Mars.

What happens to orbiting satellites, spacecraft or other materials when they reach the end of their useful life? Sadly, they become space “junk” and may pose a serious hazard to other spacecraft for years, before eventually burning up in the atmosphere. As the use of space grows, so will this problem. What can be done to fix it?


Urban Mobility

How are we moving people from point A to point B?
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Fast forward a few years from now: Several space companies have successfully and competitively reduced the cost of launch into low Earth orbit (LEO) by more than a factor of 10. The commercial space industry is thriving. There are soaring numbers of satellite launches, astronaut ferries to and from space stations, and forward movement in the human and robotic exploration of the inner solar system. How might all these spacecraft get around? The answer: Fueling stations in the sky!