Popular Mechanics (South Africa)
GOOGLE EARTH, MAPS, AND STREET VIEW
THE WORLD, IN YOUR POCKET
The Cold War drove the next leaps in mapping technology. The launch of Sputnik sparked the development of GPS when MIT scientists realised they could track the Soviet satellite from the ground by observing how its radio signal changed as it moved, and likewise, objects on Earth could be located based on their distance from satellites.
Early satellite navigation experiments were developed by the US military to track intercontinental missiles in the 1960s. And by the early 1970s, the military launched the first Global Positioning System, NAVSTAR, which could determine precise spatial coordinates for anywhere on Earth. Today, a full constellation of GPS satellites (about 27) circles the globe twice a day, transmitting radio signals. When an object on Earth’s surface receives a signal from at least three satellites, its precise geographic coordinates can be determined within centimetres.
In 2000, the US Department of Defense lifted its policy of degrading the accuracy of its GPS tracking for civilian use. From the ensuing technology boom, Google emerged with a trio of products – Earth, Maps, and Street View – that together created the most complete world map.
Released in 2005, Google Earth provided an interactive, 3D image of the globe formed from millions of overlapping satellite photographs overlaid on a 3D digital Earth. Close-up 3D details are added from aerial images that capture the depth of buildings and terrain.
Started in 2006 with vans driving around six major US cities with GPS sensors and multi-lens cameras mounted on top, Google Street View recreates the Earth from eye level. In 2017, the Street View cameras were updated with laser scanners that record the dimensions and depth of the objects being photographed to create a 3D view along the way. These cameras, aided by crowdsourced data and machine learning, have mapped millions of miles of roads across 87 countries on all seven continents. Combined with Maps, Street View and Earth literally put the world in billions of people’s hands. It is now possible to navigate and explore nearly anywhere on Earth – try Everest Base Camp or Rome’s Colosseum – with a click and zoom.