Buzz
Since the formation of the National Aeronautics and Space Administration (NASA) more than 50 years ago, the agency has launched a myriad of space missions. These missions span from deep-space probes to crewed spacecraft that have pushed the boundaries of technology and exploration.
Many of the most significant achievements in science, engineering, mathematics, and technology were directly driven by the missions detailed below. Here are some of the most remarkable and groundbreaking NASA missions ever undertaken.
10. WMAP Satellite
Did you know that humanity possesses a baby picture of the early universe?
We can't directly capture images from the moment of the Big Bang. For the first few hundred thousand years, the universe was far too hot and dense for photons to travel far. Visibility was extremely limited, with light only reaching a few light-years before being blocked by the vast hydrogen clouds that filled the universe.
But after roughly 380,000 years, the universe cooled and expanded, allowing the first light to escape. This ancient light, now known as the cosmic microwave background (CMB) radiation, reaches Earth from every direction in the sky and reveals the universe at its earliest stages.
Since the CMB's discovery, scientists have sought to map its hot and cold regions to see if they align with theoretical predictions. This data was elusive until recent decades, with the breakthrough coming when NASA’s Wilkinson Microwave Anisotropy Probe (WMAP) provided an HD image of the radiation.
The results from WMAP supported the predictions, showing that over 14 billion years ago, the universe was nearly uniform in temperature. It's astonishing that we have access to such detailed information about a time so long ago.
The WMAP satellite was launched on June 30, 2001, at 3:46 PM EDT aboard the Delta II-7425-10 rocket. By April 2002, it had completed its first observation of the CMB, and in February 2003, the first high-resolution images of the CMB were released, along with detailed papers analyzing the findings.
The research papers published from WMAP's data have become some of the most frequently cited and referenced in the field of space science.
9. Viking I and II
Before 1976, the United States had never successfully landed a probe on another planet. Parachutes and other landing mechanisms often failed, and the expensive spacecraft sent to Mars would usually crash into the surface at high speeds, making any attempt to land a costly disaster.
Getting something into orbit around Earth is already a significant achievement. But it's an even greater challenge to break free from Earth's orbit, enter orbit around another celestial body, and then land successfully on that planet. This remarkable feat was accomplished by the Viking probes.
The two Viking probes were launched within a month of each other aboard Titan IIIE/Centaur rockets, with each mission consisting of an orbiter and a lander. One part of the spacecraft was to remain in orbit around Mars, while the other was designed to land on the Martian surface.
Based on observations made from Earth, scientists believed that life couldn’t exist on Mars. However, since no one had ever landed on the planet, this was still a hypothesis. The Viking probes provided the definitive answer, returning the first images and experimental data that confirmed no signs of life, whether extraterrestrial or microbial.
8. Friendship 7
By early 1962, the United States had barely 30 minutes of experience in space, and with the decade quickly drawing to a close, the pressure was on. The US had yet to send a man into orbit—an essential step in reaching the Moon and surpassing the Soviets. That all changed with the launch of Friendship 7, the third Mercury mission.
Lieutenant Colonel John Glenn, a skilled military test pilot, was selected to pilot the new Atlas rocket into orbit. On February 20, 1962, the rocket successfully launched, completing nearly five hours in Earth's orbit. Glenn safely returned, landing about 1,300 kilometers (800 miles) south of Bermuda.
The mission's objectives—to test the new rocket, learn how to orbit Earth, and demonstrate that humans could function in space—were all successfully achieved.
7. Gemini IV
While the Mercury missions laid the groundwork for orbit, it was the Gemini missions that provided the crucial skills required for a journey to the Moon. One of the key tasks on the Moon was spacewalking—exiting the spacecraft and venturing into the vacuum of space. As this had never been done by the US before, it was vital to practice this before attempting it on the Moon.
Edward H. White II, a USAF test pilot, was selected as the first American to perform a spacewalk. Along with his crewmate James McDivitt, he launched on June 3, 1965, aboard a Titan II rocket. White’s historic spacewalk lasted 36 minutes and was completed without major issues.
The mission successfully met its objectives, which included studying the long-term effects of spaceflight (as the mission lasted four days) and conducting the first spacewalk. However, the capsule landed approximately 80 kilometers (50 miles) off course due to a mistake in the reentry calculations—the astronauts had forgotten the Earth's rotation during reentry planning.
6. STS-1
Following the success of the Apollo program, NASA began searching for its next groundbreaking project. That next step was the space shuttle—a reusable spacecraft designed to land like a glider and launch like a rocket. This vehicle would carry experiments and satellites into orbit and could stay in space for extended periods. Multiple shuttles were to be built, with Columbia being the first to undergo flight tests.
Launched on April 12, 1981, and piloted by John Young and Robert L. Crippen, the powerful rocket soared to an orbit of 166 nautical miles. The mission lasted two days and six hours, thoroughly testing the shuttle's systems and capabilities.
The shuttle made a smooth landing at Edwards Air Force Base in California. At the time, the shuttle and its external tank were painted white, a stark contrast to the familiar black, white, and orange scheme we recognize today. The orange color came from the tank’s insulating foam, which had been left unpainted to save about 270 kilograms (600 pounds) of weight.
5. The ISS Missions
The International Space Station (ISS) stands as a powerful symbol of global collaboration. With the Russians delivering the first module in the late 1990s, the station's construction spanned more than a decade.
NASA’s space shuttles played a vital role in building the station, transporting astronauts and essential parts from all corners of the globe into orbit for assembly. Crews began arriving in the early 2000s. Additionally, NASA was pivotal in the research and development of components and construction methods used on Earth.
The ISS currently orbits at an altitude of over 350 kilometers (220 miles) and travels at a speed exceeding 8 kilometers per second (5 miles per second). At the time of writing, two Americans and one Russian astronaut are aboard the station.
4. Voyager I and II
Launched in the summer of 1977 atop a Titan-Centaur rocket, the Voyager probes were set on a mission to encounter the four unexplored giant planets of the outer solar system: Jupiter, Saturn, Neptune, and Uranus. Over the next decade, the probes explored these planets in great detail.
As of now, Voyager I is in interstellar space, and Voyager II resides in the heliosheath, the outer boundary of the heliosphere—a protective bubble formed by the solar wind around the solar system. Voyager I, now more than 20 billion kilometers (12 billion miles) from Earth, holds the record as the farthest human-made object ever created.
Both probes were equipped with a phonograph record carrying a message from Earth, intended for any extraterrestrial civilization that might intercept the spacecraft. The record is expected to survive for billions of years as the probes travel through interstellar space. Even now, the probes continue to send data back to Earth, although this may soon cease as they venture further into space.
3. Apollo 11
Undoubtedly one of the greatest technological achievements in human history, the 1969 Moon landing by Apollo 11 stands as the most iconic and groundbreaking NASA mission to date. Launched on July 16, 1969, the mission's crew included Mike Collins, Buzz Aldrin, and Neil Armstrong. Both the launch and lunar orbit insertion were flawless, and the historic event was broadcast live to hundreds of millions of viewers across the globe.
The spacecraft consisted of two parts: Columbia, the command module that would remain in orbit around the Moon and return the astronauts to Earth, and Eagle, the lunar module responsible for landing on the Moon. The descent to the lunar surface took place on July 20.
With more than 500 million people watching on television, Armstrong was tasked with landing Eagle on the Moon. The descent was challenging as the planned landing area was cluttered with large rocks, creating a hazardous environment for the touchdown.
Armstrong had mere seconds of fuel left when he successfully set the lunar module down on the Moon's surface, approximately 6.4 kilometers (4 miles) from the designated landing site. As he powered off the engine and the module settled into the lunar dust, he famously declared, 'The Eagle has landed.'
During their several excursions on the Moon, Armstrong and Aldrin collected rocks, conducted experiments, spoke with the president, and famously planted and saluted the US flag. Altogether, they spent more than 20 hours walking on the Moon’s surface.
After several days, their spacecraft safely returned to Earth, having paved the way for five additional lunar missions to follow in the coming years.
2. Apollo 8
As President John F. Kennedy's ambitious goal of landing a man on the Moon by the end of the 1960s grew closer, time was quickly running out. With just over a year remaining until the decade turned, NASA was working at an extraordinary pace.
Apollo 8 became the first crewed spacecraft to leave Earth's orbit and journey toward the Moon. The stakes were high—if they missed their trajectory, they would drift endlessly into space. If they approached too quickly, they risked colliding with the Moon at a speed of several kilometers per second.
Launched on December 21, 1968, aboard the Saturn V—the most powerful rocket ever built—Apollo 8 entered lunar orbit on Christmas Eve 1968. In a historic broadcast, the crew sent a holiday message from space, showing the Earth rising above the Moon. This broadcast was transmitted live across the globe.
After completing 10 orbits around the Moon, Apollo 8 altered its trajectory and made a successful splashdown in the Pacific Ocean on December 27.
1. Curiosity
Launched in late 2011 aboard an Atlas V rocket, the Curiosity rover was equipped with some of the most advanced—and costly—scientific instruments and technologies ever developed.
In August 2012, the Curiosity rover made a successful landing on Mars, thanks to an innovative landing technique. It descended with a parachute, and just before it hit the surface, the parachute detached, and rockets slowed its descent for a soft landing.
Curiosity's primary mission is to build on the findings of the Viking missions and investigate whether Mars ever had the right conditions for microbial life. So far, it has uncovered signs that Mars might have once supported microscopic life, though the research is still ongoing.
