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Giant Rockets for Space ExplorationThroughout the history of human spaceflight, NASA and other space agencies have built some serious rockets: behemoths of space that aimed to send astronauts to the moon, Mars or elsewhere in deep space.
Take a look at some of the tallest rockets in history, and NASA's latest entry: the Space Launch System to fly in 2017.
NASA's Mighty Saturn 5Slide 2 of 13
NASA's Mighty Saturn 5The reigning champion of giant rockets is NASA's massive Saturn 5, a three-stage booster used to launch American astronauts to the moon in the late 1960s and early 1970s.
Like the Ares I-X and NASA shuttles, the towering Saturn V launched from the Kennedy Space Center in Florida. It stood 363 feet (110 meters) high and remains the most powerful rocket ever built, even though the last one flew in 1973.
The rocket could launch payloads of up to 45 tons to the moon, or 120 tons into Earth orbit. It weighed 6.5 million pounds (3 million kg) fully fueled at liftoff. The Ares I-X weighs 1.8 million pounds (816,466 kg), slightly less than the full Ares I rocket.
That last Saturn V was a modified version that launched NASA's Skylab space station. Smaller versions of the Saturn rocket were used to launch astronauts to Skylab, with the last one — a 224-foot (68-meter) Saturn 1B — launching in 1975 to fly Apollo astronauts to meet a Soviet Soyuz spacecraft during the Apollo-Soyuz joint mission.Slide 3 of 13
Ill-fated N-1Slide 4 of 13
Ill-fated N-1A close second in the giant rocket race is the former Soviet Union's N-1 rocket, an enormous booster designed to launch cosmonauts to the moon during the Space Race with the United States.
The giant rocket stood nearly 345 feet (104 meters) tall, had five distinct stages and resembled a huge, tapering cone that was about 55 feet (17 meters) wide at the base. During launch, it weighed 6.1 million pounds (2.7 million kg) and was envisioned to launch payloads of up to 95 tons to space to send cosmonauts to the moon, according to the Russian space history website Russianspaceweb.com. [Infographic: Moscow's Secret Moon Plan - The N-1 Rocket]
But the N-1 rocket never successfully reached space, despite four attempted launches. It exploded during all four attempts between 1969 and 1972.
The former Soviet Union did have other hefty rockets in its space launch inventory: the enormous D-1E and D-1 variants of the Proton used for the 1968 lunar probe missions and 1971 Salyut 1 space station launch. Neither came close to the N-1's towering stature.
Today, Russia still uses Proton rockets and smaller Soyuz boosters to launch satellites into orbit, though cosmonauts continue to ride only Soyuz rockets into orbit. The country is also developing a new family of Angara rockets.Slide 5 of 13
Delta 4 HeavySlide 6 of 13
Delta 4 HeavyThe tallest 21st century rocket in regular service in the United States currently is the Delta 4 Heavy, a heavy-lift version of the United Launch Alliance's Delta 4 booster.
Standing 235 feet (72 meters) tall, the Delta 4 Heavy made its launch debut in 2004, but suffered a sensor glitch that prevented it from reaching its intended orbit. The problem was promptly fixed. The rocket most recently launched a classified satellite for the National Reconnaissance Office in January.
The Delta 4 Heavy is actually a group of three boosters, each called a Common Booster Core, arranged in a line to give it a three-column look. At least two more Delta 4 Heavy missions are expected on the books for future classified satellite launches, according to Spaceflight Now.
The rocket is capable of launching payloads of up to 24 tons to low-Earth orbit and 11 tons toward the geosynchronous orbits used by communications satellites, according to Spaceflight Now. The Delta 4 Heavy is also touted to be able to launch 11-ton payloads on trans-lunar injection orbit routes toward the moon and 8.8-ton payloads on Mars-bound trajectories, Spaceflight Now has reported.Slide 7 of 13
NASA's Ares 1 Rocket/Liberty BoosterSlide 8 of 13