Asked by: Tom Nicholson, Derby
Space agencies like NASA often make use of the gravitational fields of planets to give probes a boost to their final destination. In the late 1970s, mission designers began plotting out the paths between the planets and their satellites that could exploit this fuel-saving effect. The resulting ribbon-like network of celestial routes is known as the Interplanetary Superhighway, and it’s now regularly exploited on missions to deep space.
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