In the days and weeks that followed, the whole world tracked Sputnik's progress as it orbited the globe time and again. Naked-eye observers could see its pinpoint of reflected sunlight tracing across the night sky, and radios picked up the steady series of beeps from its transmitter. For Americans it was a shocking realization. Here, at the height of the Cold War, was the enemy flying right overhead. For the nascent U.S. space program, it was also a clear indication that the race into space was well and truly on—and that the United States was behind.

That race would ultimately lead to what has been called the most spectacular engineering feat of all time: landing humans on the Moon and bringing them safely back. But much more would come of it as well. Today literally thousands of satellites orbit the planet—improving global communications and weather forecasting; keeping tabs on climate change, deforestation, and the status of the ozone layer; making possible pinpoint navigation practically everywhere on Earth's surface; and, through such satellite-borne observatories as the Hubble Space Telescope, opening new eyes into the deepest reaches of the cosmos. The Space Shuttle takes astronauts, scientists, and engineers into orbit, where they perform experiments on everything from new medicines to superconductors. The Shuttle now also ferries crews to and from the International Space Station, establishing a permanent human presence in space. Venturing farther afield, robotic spacecraft have toured the whole solar system, some landing on planets and others making spectacular flybys, sending back reams of data and stunning close-up images of planets, moons, asteroids, and even comets.

In making all this possible, aerospace engineers have also propelled advances in a wide range of fields, from electronics to materials composition. Indeed, even though some critics contend that spaceflight is no more than a romantic and costly adventure, space technologies have spawned many products and services of practical use to the general public, including everything from freeze-dried foods to desktop computers and Velcro.