On Sept. 16, 1949, the U.S. launched a V-2 rocket with a monkey named Albert III on board.

Albert III was the third monkey the U.S. attempted to launch to space. He was also the third one to be killed on the job. The U.S. precursor to NASA began launching monkeys into space in the 1940s to try to see what might happen to humans in space.

This testing started more than a decade before any humans were launched up there. The monkeys were all given anesthetics and covered with sensors and probes that monitored their vitals. While the other five Alberts that were launched on V-2 rockets were all rhesus monkeys, Albert III was actually a long-tailed macaque. Sadly, Albert III died when his rocket exploded 10 seconds after launch.

The two Alberts who came before him died differently, first by suffocation and then by a parachute that failed to deploy before landing. It wasn't until the Albert VI flew in 1961 that a test monkey survived a test launch. NASA stopped using monkeys for launch testing in the 1980s.

Why it mattered

In the late 1940s, the United States was just beginning to gain experience with large rocket and ballistic missile launches using a cache of V-2 rockets (and the German rocket scientists like Werhner von Braun that designed them). And while the U.S. military sought to develop rocket and missile weapons, animal launches like the failed flight of Albert III were aimed studying how the upper atmosphere and cosmic rays could affect living things (like future astronauts).

To do that, the U.S. Air Force formed Project Blossom, a series of V-2 rocket launches out of White Sands Missile Range in New Mexico that included five "biological flights" overseen by the Aero-Medical Laboratory at Wright-Patterson Air Force Base, according to a history by the White Sands Missile Range Museum.

Albert III's launch failed 24.7 seconds after liftoff, with the V-2 rocket flying at a slower speed than expected after liftoff, the museum account states. The rocket suffered an explosion in its tail section 10.7 seconds into the flight, then another one 14 seconds later (likely due to leaks in its alchol fuel system). It reached a maximum altitude of just 3 miles before the failure.

Despite the failure, military scientists took what they learned from Albert III's launch to make design improvements in future tests. There were still failures (the next monkey launch of Albert IV did not succeed), and three of the seven Project Blossom launch tests failed in all.

The first successful monkey launch carried Albert VI (and 11 mice) to suborbital space and back on a new Aerobee rocket on Sept. 20, 1951, NASA has said.

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On Sept. 15, 1968, the Soviet Union launched the Zond 5 spacecraft on a mission to loop around the moon and return to Earth. There were no cosmonauts aboard, but there were several smaller vertebrates — including the first two tortoises to ever go to space!

Other passengers included wine flies, mealworms, plants and seeds. These were the first animals in deep space and the first to travel around the moon.

• Photos: Pioneering Animals in Space

After looping around the moon, the Zond 5 spacecraft turned around and came back to Earth. It was supposed to land in Kazakhstan on Sept. 22, but the spacecraft's guidance system failed, and it splashed down in the Indian Ocean instead.

The Soviets did recover the capsule and found that the tortoises and other critters were still alive, although they had lost some weight since the start of the mission.

Why it mattered

In September of 1968, the Space Race to the moon was in full swing. NASA was just three months away from the historic Apollo 8 mission, which sent the first astronauts around the moon in daring first-of-its-kind mission.

But with Zond 5, the Soviet Union scored an early win for the first circumlunar flight that launched from the Earth to the moon, then returned for a landing (or splashdown, in this case). In fact, the flight may have spurred NASA to launch Apollo 8.

"The flight of Zond 5 caused concern in the U.S. that the Soviets would place cosmonauts aboard the next Zond and complete the first crewed circumlunar mission. At about this time, a U.S. Corona reconnaissance satellite photographed an N-1 rocket on its pad at Baikonur," NASA wrote in a report, adding that NASA's then-chief James Webb likely saw those intelligence reports.

"The apparently successful Zond 5 mission coupled with the photos of the Soviet lunar booster on the launch pad may have contributed to the decision to send Apollo 8 on its circumlunar mission in December 1968, bringing the moon landing one step closer."

Zond 5 launched from Baikonur Cosmodrome atop a Proton rocket and took three days to reach the moon. The two tortoises on board were, appropriately, Russian steppes tortoises, NASA has said. After looping around the moon, the critters spent a few more days in transit for the trip home.

It was a guidance system error that led the Zond 5 capsule to splash down in the Indian Ocean instead of landing on land as planned. But the landing on Sept. 21 wasn't the end of the road for the Zond 5 tortoises and other animals.

The Soviet recovery ship Vasily Golovnin plucked the Zond 5 capsule from the ocean and returned to port in what is now Mumbai, India on Oct. 3, weeks later! They wer ethen flown to Moscow on an Antonov-12 cargo plane before the capsule was finally opened to find the tortoises alive and in good health. You can still view the Zond 5 capsule at the RSC Energia museum in Korolev.

Cassini's Grand Finale death dive at Saturn in 2017

A bunch of space traveling tortoises and other animals aren't the only notable space event that happened today in history.

On Sept. 15, 2017, NASA's Cassini spacecraft died in a blaze of glory as it crashed into Saturn after 13 years orbiting the ringed planet. NASA ended the mission in a fiery plunge because Cassini was running out of fuel and the space agency wanted to ensure it wouldn't crash into one of Saturn's icy moons, like Enceladus, and contaminate them. They called it Cassini's Grand Finale.

Launched in 1997, the $3.26 billion Cassini mission entered orbit around Saturn in 2004 and dropped a European Huygens probe onto the cloudy moon Titan in early 2005. The mission was expected to last until 2008, but was extended twice, ultimately stretching through to September 2017.

During its mission life, Cassini discovered a trove if new Saturn moons, found a strange hexagon at the planet's north pole and tracked mesmerizing details of the planet's many rings.

"Congratulations to you all," Earl Maize, the Cassini program manager, said to the mission team after the spacecraft signal was lost."This has been an incredible mission, an incredible spacecraft, and you're all an incredible team. I'm going to call this the end of mission."

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On Sept. 14, 1966, NASA's Gemini 11 mission set an spaceflight altitude record that lasted for nearly six decades when two astronauts reached an orbit of 850 miles above the Earth. It remained the highest altitude ever achieved by a crewed, non-lunar mission until 2024.

Gemini 11 command pilot Pete Conrad and pilot Dick Gordon spent three days orbiting the Earth in their cramped Gemini spacecraft. After launch, they performed the first-ever direct-ascent rendezvous with an Agena target vehicle.

Once the two spacecraft were adjoined, they used the rocket on the Agena target vehicle to ascend to their record-breaking altitude. They also created a little bit of artificial gravity while in orbit by using their thrusters to rotate the combined spacecraft.

Why it mattered

Despite its name, Gemini 11 (or Gemini XI) was actually NASA's ninth crewed mission of the two-person Gemini spaceflights. The mission was relatively short, just three days, and included two spacewalks, and what NASA calls the first orbital rendezvous and docking with an Agena target vehicle (the first in-space docking occurred three missions earlier on Gemini 8).

But for 58 years, the Gemini 11 mission marked the highest astronauts flew above Earth without going to the moon. The astronauts used the rocket engine on the Agena booster to raise the orbit of their docked spacecraft to reach a peak altitude of 853.8 miles (1,374.1 kilometers).

Conrad and Gordon performed eight different science experiments, but perhaps one of their most striking feats was the artificial gravity demonstration. During one of his spacewalks, Gordon attached a 30-meter tether from the Agena booster to the Gemini capsule. After reaching their peak altitude, Conrad undocked the capsule from the Agena, backing away them starting a rotation that created a very slight "gravitational acceleration," NASA said. They spun together for 3 hours, before the tether was cut loose and Gemini 11 left the Agena behind.

Conrad and Gordon also performed the first automated reentry during their landing, with their Gemini 11 capsule flying itself in a first-ever for NASA.

The Earth orbit altitude record set by NASA's Gemini 11 mission stood until Sept. 10, 2024, when the private SpaceX mission Polaris Dawn, bankrolled by American billionaire Jared Isaacman (currently serving as NASA administrator), launched into an orbit that reached 870 miles (1,400.7 kilometers).

That Polaris Dawn mission also included a spacewalk by Isaacman and SpaceX's Anna Menon, marking the first-ever private spacewalk.

On Sept. 13, 2007, Japan launched the Kaguya spacecraft on a mission to the moon. Formally known as SELENE, which is short for SELenological and ENgineering Explorer, it was Japan's second moon mission.

Kaguya launched from Tanegashima Space Center on a Japanese H-IIA rocket and looped around the Earth twice before heading to the moon. NOTE: While the launch occurred on Sept. 13 in the evening Eastern Time, it was actually 10:31 a.m. on Sept. 14 at the launch site. The spacecraft carried 14 science instruments and two tiny microsatellites to map the moon's surface and study its gravitational field.

After a 20-day journey, Kaguya arrived at the moon. The mission consisted of three spacecraft: a main orbiter, a small communications satellite, and a third small satellite to map the moon's gravitational field. After about a year of lunar observations, the mission ended with a planned crash landing on the lunar surface.

Why it mattered

The Kaguya moon mission was actually the second lunar probe launched by Japan, but it was the country's first spacecraft to actually orbit the moon. (Japan's Hiten spacecraft launched in 1990, but it flew in a highly elliptical orbit around Earth that allowed it to make 10 flybys of the moon before crashing into the lunar surface in 1993. It also released a small probe called Hagoromo near the moon.)

But while the Hiten and Hagoromo missions were designed to test technology for a future moon mission, Kaguya put all that tech into practice. The probe was renamed after the moon princess Kaguya-hime from a Japanese folktale shortly after launch as a result of a public poll. The two small satellites it carried were named Okina (a relay satellite) and Ouna (a radio source experiment).

While Kaguya carried an intricate set of science instruments, it was the views from its two primary high-definition cameras that wowed the public. With them, Kaguya captured the first-ever HD video and images of the moon, including spectacular new videos of Earthrise (the Earth rising over the moon) - something not seen since NASA's Apollo missions.

The spacecraft also created an complete topographical map of the moon, detected gravity anomalies on the near and far side of the moon and captured the first optical observations of the permanently shadowed interior of Shackleton Crater near the moon's south pole, according to a NASA review.

Kaguya completed its primary mission in October 2008 and JAXA mission planners had hoped to extend its moon flight through early 2009, but a faulty reaction wheel forced them to call off the extended mission early. They ultimately directed Kaguya to crash into the moon on Feb. 12, 2009, with the impact occurring near Gill Crater.

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On Sept. 12, 1992, NASA astronaut Mae Jemison became the first African American woman to go to space.

In NASA's early days, women and people of color were never selected to go to space. NASA didn't send a woman to space until the seventh space shuttle mission in 1983. NASA launched the first Black man in space, astronaut Guion Bluford, on the following mission that same year.

• Women in Space: A Gallery of Firsts

But it would take another nine years for NASA to finally select a Black woman to fly on STS-47, the 50th space shuttle mission. Jemison was a trained engineer and licensed physician who served in the Peace Corps before applying to become an astronaut.

She worked as a mission specialist on STS-47 and logged over 190 hours in space. STS-47 was her only mission. In 1993, she retired from NASA and went on to found her own company, the Jemison Group, which is a technology consulting firm.

Why it mattered

Mae Jemison's historic launch on STS-47 was a milestone for Black astronauts and NASA's growth into a more diverse space agency.

Jemison, who was born in Alabama and grew up in Chicago, joined NASA's astronaut corps in 1987 as an astronaut candidate after years working as a the Area Peace Corp Medical Officer for Sierra Leone and Liberia in West Africa (from 1983 to 1985). Before that, she earned a bachelor's degree in chemical engineering from Stanford University (where she also studied African American Studies), and later a doctorate in medicine from Cornell University. She was serving as a General Practitioner in medicine when she applied to be a NASA astronaut.

Jemison has said she was fascinated by space from a young age and found inspiration the Star Trek's Lt. Uhura, a Black woman in space on television, before going on to university. (We'll return to Star Trek in a minute).

As the science mission specialist on STS-47, Jemison oversaw 44 different experiments for Japan and the United States inside the Spacelab module aboard space shuttle Endeavour. She was also the co-investigator on a bone cell study that flew on the same mission.

Jemison spent eight days in orbit on STS-47, logging 190 hours, 30 minutes and 23 seconds in space, before returning to Earth on Sept. 20, 1992. It would be her only spaceflight.

Jemison retired from NASA in 1993 and founding her Jemison Group. as a consulting firm that same year. Remember Jemison's Star Trek inspiration? It came full circle in 1993 when Jemison appeared as a lieutenant on "Star Trek: The Next Generation" in the episode "Second Chances" during the sixth season.

Jemison has also led the 100-Year Starship project to encourage the development of a mission visit another star. In 2017, Jemison became an official Lego minifigure in the Women of NASA Lego set.

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On Sept. 11, 1985, the International Cometary Explorer, or "ICE," became the first spacecraft to fly by a comet.

Originally launched as the International Sun-Earth Explorer-3 in 1978, ICE was one of three spacecraft built for the International Sun-Earth Explorer (ISEE) program, a joint effort by NASA, the European Space Research Organization and the European Space Agency.

The program's purpose was to study space weather, or the interaction between the Earth's magnetic field and the solar wind. After completing its original mission, the spacecraft did a maneuver to steer it toward Comet Giacobini-Zinner. It flew straight through the comet's plasma tail, but it didn't stop there! Six months later, it flew by Halley's Comet, too.

Why it mattered

The International Cometary Explorer has gone down in history as a mission of epic firsts, many of which occured after it completed its primary mission.

As mentioned above, NASA, ESA and the European Space Research Organisation teamed up to build and launch the probe in 1978, when it was called the International Sun-Earth Explorer 3, or ISEE-3. The mission was the third of three to study the sun-Earth environment, with ISEE-3 aimed at studying energetic particles, electric and magnetic fields and the plasma environment. It carried 14 different instruments, including a solar wind detector and gear to measure cosmic rays, X-rays and gamma rays.

For its primary mission, ISEE-3 flew to the L1 Lagrange point about 1 million miles (1.5 million kilometers) from Earth on the sun-facing side and spent three years conducting science. It was the first spacecraft ever to orbit a Lagrange (or libration) point, NASA has said.

But it was in 1981, once ISEE-3's core mission was over, that things got interesting for comet fans. NASA scientists at Goddard Space Flight Center in Maryland decided to squeeze more science from the probe by sending it through Earth's magnetic tail (another first), and then on to visit a comet.

That began in 1982, with the probe firing its thrusters and performing five flybys of the moon to set course for Comet 21P/Giacobini-Zinner. It was only then, once ISEE-3 was on course for the comet, that it was renamed the International Cometary Explorer, or ICE.

On Sept. 11, 1985, the spacecraft flew within 4,885 miles (7,862 km) of Comet 21P, confirming many theories about comets (including that they are dirty "snowballs" of the solar system) and collected detailed data about its tail. It also took a long-distance look at Halley's Comet on March 28, 1986, when it passed by at a range of 25 million miles (just over 40 million km).

While NASA shut down the ICE/ISEE-3 mission in 1995, it saw renewed interest in 2014 when a group of independent scientists attempted to reactivate the probe when its orbit brought it near Earth in August 2014. At the time, the probe still had five operational instruments and an active transmitter that allowed NASA to track it across the solar system. The group raised $125,000 in crowdfunding to support their effort.

The science group managed to successfully fire ICE/ISEE-3's thrusters on July 2, 2014, but subsequent efforts failed and it flew past the moon and continued on its long orbit around the sun. It should return near Earth sometime in 2031, NASA has said.

A tragic day seen from space

Another major event occurred in space history on Sept. 11, this time in 2001.

On that day, NASA astronaut Frank Culbertson was the only American in space to see the tragic 9/11 terrorist attacks on New York City, Washington, D.C. and Pennsylvania as part of a three-man crew on the International Space Station.

Culbertson was commander of Expedition 3 to the ISS and led a crew that included Russian cosmonauts Vladimir Dezhurov and Mikhail Turin.

"I didn't know exactly what was happening, but I knew it was really bad because there was a big cloud of debris covering Manhattan," Culbertson said in a NASA video released in 2011. "That's when it really became painful, because it was like seeing a wound in the side of your country, of your family, your friends."

You can learn more about Culberton's observations of the 9/11 attacks from space at NASA's Remembering 9/11 site here.

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On Sept. 10, 2011, NASA's GRAIL spacecraft launched on a mission to the moon!

GRAIL, which stands for Gravity Recovery and Interior Laboratory, was sent to the moon to map its gravitational fields. Scientists could study the moon's interior structure by looking at maps of the moon's gravity.

Asteroid impacts from billions of years ago left dense pockets of material under the lunar surface, which can exert extra gravitational pull on spacecraft orbiting the moon. So by measuring that gravitational pull, the GRAIL mission could reveal information about what lies beneath the surface.

The mission actually consisted of two twin spacecraft named Ebb and Flow, which would fly in tandem around the moon to map variations in its gravitation field. Both lifted off on the same Delta II rocket from Cape Canaveral, Florida and arrived in lunar orbit almost four months later.

They mapped the moon for about nine months before NASA decided it was finished with the mission, and the two orbiters crashed into the moon.

Why it mattered

The moon is a weird place. It may look like a cold, gray ball of solid rock, but its density varies from location to location due to odd "mass concentrations" (or mascons for short) buried under the lunar surface. That leads to a strange, lumpy gravity that's not uniform across the lunar surface.

• Holy GRAIL! Photos From NASA's Moon Gravity Mission

That's where GRAIL's Ebb and Flow probes came in. Each of the twin spacecraft carried three instruments to map the interior of the moon. Those included a Lunar Gravity Ranging System, a Radio Science Beacon and a camera called MoonKam Lunar-Imaging system.

Together, the instruments mapped the mascons on the moon in extreme detail to monitor where lunar gravity increased from the norm. Astronomers had long suspected that mascons on the moon and other planets formed during violent asteroid impacts.

"GRAIL data confirm that lunar mascons were generated when large asteroids or comets impacted the ancient Moon when its interior was much hotter than it is now," Jay Melosh, a GRAIL co-investigator at Purdue University, said in a NASA overview.

The MoonKam tool was actually a student experiment (MoonKam is short for Moon Knowledge Acquired by Middle School Students). It was built by undergradutate students at the University of California, San Diego in partnership with the Sally Ride Science foundation to encourage younger students to study science and space. (The names Ebb and Flow as GRAIL probe names were also suggested by 4th grade students at Emily Dickinson Elementary School in Bozeman, Montana, as part of a national competition.)

The $496 million GRAIL probes orbited the moon in an extremely low orbit, coming within 30 miles (50 km) of the lunar surface at their closest approach. They were separated from each other at distances that ranged from 109 miles to 140 miles (175 km to 225 km).

NASA crashed the GRAIL probes into the moon on Dec. 17, 2012 once its fuel reserves reached the point that it could not maintain its low lunar orbit. They crashed into a crater rim near the moon's north pole to prevent them from randomly crashing uncontrolled into someplace like an historic Apollo moon landing site.

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On Sept. 9, 1982, the first private rocket launched from a Texas cattle ranch.

The Conestoga 1 rocket was designed by Space Services Inc. of America (SSIA) and built from spare parts of other rockets. It was named after a type of covered wagon that used to transport American settlers westward to the new frontier during the 19th century.

The 36-foot rocket lifted off from a private launch facility on Matagorda Island, Texas and flew for 10-and-a-half minutes. It reached an altitude of 195 miles and became the first privately funded rocket to reach space.

The only payload on board was 40 gallons of water, which didn't serve much scientific purpose, but it was ejected from the spacecraft at peak altitude to serve as a visual marker so ground crews could watch.

Why it mattered

Private rocket launches may seem routine today (SpaceX alone launches hundreds each year), spaceflight in 1982 was primarily the purview of government agencies like NASA, the U.S. military and other national agencies.

That changed with the launch of Conestoga 1 by SSIA. The company, led at the time by legendary Mercury 7 and Apollo-Soyuz astronaut Deke Slayton, and entreneurs Charles Chafer and David Hannah, Jr., was based in Houston and raised $6 million from 57 supporters to develop their rocket, according to Wired. The company initially tried to launch a different type of rocket, called Percheron, in 1981, but it exploded on the pad, according to an account by Inc. magazine.

SSIA found success three years later with Conestoga 1, a solid-fueled rocket based on an old Minuteman missile second stage (which Wired said SSIA bought from NASA for $365,000). It launched on its suborbital mission from Matagordo Island, Texas, which is about 170 miles (274 km) north of what is now Starbase, Texas, home to SpaceX's Starship megarocket launches.

SSIA would go on to launch another suborbital sounding rocket carrying science experiments in 1989. The company attempted to launch a larger Conestoga rocket (Conestoga 1620), which included additional strap-on boosters, in October 1995 from NASA's Wallops Flight Facility on Wallops Island, Virginia, but it failed 46 seconds after liftoff, according to NASA.

Today, SSIA's subsidiary Celestis, a space funeral company, now offers memorial flights by arranging to fly human cremains into space on commercial spaceflights. (SpaceX's Falcon 9 rockets have carried some such payloads. Another branch offers informal star naming services.

But the legacy of Conestega 1 lives on today in a robust commercial space launch industry that has seen a number of private companies enter the space marketplace. SpaceX, Blue Origin, Virgin Galactic and Scaled Composites have even built and flown private astronauts on suborbital (and orbital in SpaceX's case) missions. SpaceX, meanwhile, has built and launched the largest private rocket on Earth, the Starship and Super Heavy booster. It stands over 400 feet tall, is more powerful than NASA's mighty Saturn V moon rocket, and is designed to be fully reusable to allow missions to Earth orbit, the moon and Mars.

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On Sept. 8, 2004, NASA's Genesis spacecraft crash-landed in Utah after its parachutes failed to deploy.

Genesis was NASA's first sample-return mission since the Apollo program, and the first attempt ever to bring back samples from someplace farther than the moon. The spacecraft picked up solar wind particles while orbiting the L1 Lagrange point, which is about 1 million miles from Earth. L1 is a "sweet spot" between the Earth and the sun, where the gravitational pull from both objects balances out.

Genesis collected samples of the solar wind using arrays made of ultrathin semiconductors called "wafers." Atoms and ions floating around in space stuck to these wafers, and Genesis was supposed to bring them back safely. But that didn't happen, because its parachute didn't work.

Instead, Genesis tumbled from the sky and slammed into the Utah desert. Scientists literally had to pick up the pieces after the wafers containing the solar wind samples shattered into thousands of tiny shards. Luckily, scientists were still able to salvage some of the samples.

Why it mattered

NASA's Genesis probe launched in August 2001 on a $264 million mission to collect samples of the solar wind. It was the first time NASA tried a sample-return mission since Apollo 17 in 1972 (which was a crewed flight), and this trip would be fully robotic.

In order to secure the Genesis solar wind samples safely, NASA opted for a tried and true approach for space retrieval: capturing a returning craft by the parachute using a helicopter. Similar techniques were used in the past to collect spy satellite film from military satellites.

But a design flaw in the parachute system, and a fairly basic one at that, doomed the Genesis spacecraft. Four gravity switches in the sample-return canister were installed backwards due to an error in the design schematics. It affected both the primary and backup parachute systems.

The switches were supposed to detect when Genesis began braking in Earth's atmosphere and trigger parachute deployment. That never happened, so the probe crashed into Earth instead.

NASA scientists were still able to glean some science from the shattered Genesis sample-return capsule, but the result was far from optimal, as you'd expect. The mishap also prompted reviews of NASA's Stardust comet sample return probe, which used the same type of gravity switches, but that spacecraft's switches were installed correctly and it made a successful landing in 2006.

Happy Birthday, Star Trek!

Speaking of things flying through space. There was another event that occurred on this day in 1966 that - while not actually being in space - has influenced our concept of spaceflight for a decade.

On Sept. 8, 1966, the first episode of "Star Trek" debuted on television. The iconic science fiction series, which has spawned a myriad of spin-offs and feature films (not to mention all the merch), has inspired countless engineers, scientists and space fans over six decades.

The Star Trek franchise celebrates its 60th anniversary in 2026, and you can find our Star Trek coverage here.

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On Sept. 7, 1995, the space shuttle Endeavour launched on mission STS-69. This was the 100th successful crew spaceflight mission for NASA.

Endeavour lifted off from NASA's historic Pad 39A launch site at the Kennedy Space Center in Florida. During the 11-day mission, five crewmembers did science experiments, deployed and retrieved a satellite called Spartan 201, and conducted a nearly seven-hour-long spacewalk to practice methods future astronauts would use to build the International Space Station.

The astronauts also deployed the Wake Shield Facility, a saucer-shaped satellite that flew free of the shuttle for several days. This was the first time two different payloads were retrieved and deployed during the same mission.

Why it mattered

The launch of STS-69 on space shuttle Endeavour was a milestone of sorts for NASA and U.S. space exploration. As the 100th crewed flight by NASA astronauts, it showed that flying humans in space was not a one-off or occasional feat.

The five-astronaut crew was commanded by David Walker, with Kenneth Cockrell as pilot. Astronaut Jim Voss served as payload commander (remember, this was the first time two different payloads would be deployed in space), with astronauts Jim Newman and Michael Gernhardt rounding out the team as mission specialists.

The Spartan 201-03 payload was an experiment designed to study the sun's outer atmosphere as it transitioned into solar wind. It was the third of four such Spartan 201 flights on a NASA space shuttle.

The Wake Shield Facility-2, meanwhile, was a sort of in-space factory. The saucer-shaped platform was actually a stainless steel disk designed to create an "ultravacuum environment" in space in order to grow thin films that could be used for new advanced electronics. The disk was actually deployed twice during the 11-day mission and successfully grew four thin films of seven planned, while also performing an electrical field experiment for the U.S. Air Force on its second deployment.

The one spacewalk of the mission was performed by astronauts Voss and Gernhardt, who spent 6 hours and 46 minutes working outside Endeavour to test new thermal upgrades to NASA's extravehicular activity (or EVA) suits, as well as new tools and techniques to build the then nascent International Space Station.

There was one space oddity on this STS-69 mission, according to NASA. The crew was NASA's second "dog crew," or Dog Crew II, with each of the astronauts adopting a dog nickname.

"Walker was Red Dog; Cockrell was Cujo; Voss, Dog Face; Newman, Pluto; and Gernhardt, Under Dog," NASA said in an overview.

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On Sept. 6, 1947, a rocket launched from an aircraft carrier for the first time. The V-2 rocket was captured from a German manufacturing site by the Allied forces at the end of World War II.

V-2s were the world's first long-range guided ballistic missile. They were designed by German rocket scientist Wernher von Braun, a famous aerospace engineer, invented them for Nazi Germany before he was secretly moved to the U.S. and started working for NASA. Von Braun and the seized V-2 missile parts were brought to the White Sands Missile Range in New Mexico, where the scientists assembled the parts and began experimenting with launches.

The first V-2 to launch at sea blasted off from a U.S. Navy ship called the USS Midway in a mission titled "Operation Sandy." The aircraft carrier sailed a few hundred miles south of Bermuda for the launch. After liftoff, the V-2 started tilting midair and only made it to an altitude of 15,000 feet (4,600 meters) before falling back to Earth.

Why it mattered

Rockets may be great for space exploration, but the technology's roots are firmly embedded in military applications, with the V-2 rocket standing out as a clear example.

The rocket was designed as a military weapon first and foremost, and it was U.S. military's push to secure such tech that led to Operation: Paperclip, which secreted Von Braun and many other German aerospace scientists out of Germany at the end of World War II.

Operation: Sandy marked the first ballistic missile launch by the U.S. Navy, but today the such missiles are a standard part of the arsenal of some ships. That all started with the 1947 test flight. It also marked a step forward in U.S. missile technology, which would later evolve into orbital rockets just over a decade later.

While the V-2 rocket that launched from the USS Midway veered off course and began to break apart at an alttude of about 12,000 feet, according to MidwayCurrents.org, it did prove the concept of a missile launch at sea.

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On Sept. 5, 1977, Voyager 1 began its epic journey through deep space with a glorious morning launch from Cape Canaveral, Florida.

Voyager 1 initially launched on a mission to explore the outer planets. After flying by Jupiter and Saturn in 1979 and 1980, the spacecraft took a sharp turn and started heading straight out of the solar system.

Voyager 1 became the first spacecraft to reach interstellar space in 2012, although scientists are still debating about exactly where that boundary lies.

The spacecraft's next big encounter will take place in about 40,000 years, when it will fly by another star system. And just in case it comes across any intelligent life out in the universe, it's carrying a golden record with sights, sounds and greetings from planet Earth.

Why it mattered

Voyager 1 is a space exploration icon and NASA's ultimate long-lasting mission.

The spacecraft was part of a two spacecraft mission (Voyager 2 launched a few weeks earlier) to explore the outer solar system like never before. While Voyager 2 launched on a four-planet "Grand Tour" of the solar system, a trajectory that included flybys of Jupiter, Saturn, Uranus and Neptune, it wasn't the fastest of missions.

Voyager 1 launched on a fast-track to Jupiter. In fact, the probe actually overtook Voyager 2 on the way to Jupiter and arrived their first for a flyby in March 1979. A year later, in November 1980, Voyager 1 passed by Saturn in a flyby that shot it out of the solar system.

By Feb. 17, 1998, Voyager 1 grabbed the record as the farthest human-built object after it flew farther than Pioneer 10 and in 2012, the spacecraft became the first probe ever to enter interstellar space. It remains NASA's farthest flung mission still active today.

Today, Voyager 1 is 15.9 billion miles (171.6 astronomical units) from Earth and still flying. Even 49 years after launch, the spacecraft is still collecting some data, but its nuclear radioisotope thermoelectric generator does not produce as much power as it did at launch, so NASA teams have steadily shut down heaters and unneeded instruments over the decades.

Earlier this year, on April 17, NASA commanded Voyager 1 to shut down its low-energy charged particles experiment to save power. For nearly 50 years, the instrument has provided constant measurements on the ion, electron and cosmic ray environment in deep space.

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On Sept. 4, 1962, NASA's Mariner 2 spacecraft performed the first-ever rocket maneuver in deep space as it did a quick mid-course correction on its way to Venus. It had launched just eight days earlier and needed to burn its engines to ensure that its trajectory would take it to Venus.

The midcourse maneuver was necessary because the Atlas-Agena rocket that launched Mariner 2 didn't launch with enough accuracy to get the trajectory right in one shot. When it was about 1.5 million miles (2.4 million km) from Earth, it fired its engines to help steer it in the right direction.

The entire maneuver required five separate commands sent from mission control, telling the spacecraft to roll, pitch, turn and burn its motor. One hundred days later, Mariner 2 flew by Venus and became the first spacecraft to successfully fly by another planet.

Why it mattered

Tweaking a spacecraft's course in deep space seems a bit routine these days (NASA's newly launched Roman Space Telescope just performed such a feat this week), but in 1962 -- when reaching another planet with a probe was still the stuff of fiction -- it was far from a safe bet.

Mariner 2 launched in Aug. 27, 1962 on what would eventually be the first successful misson to another world. But as stated above, the launch wasn't accurate enough to place Mariner 2 on a direct course for Venus.

That's where the mid-course correction came in. The mission team designed a short engine burn that directed Mariner 2 to roll itself about 9.33 degrees, pitch its nose around 139.83 degrees so that it could turn its rocket engine to face forward, firing the engine, as Time Magazine recounted. The entire process took up to 36 minutes.

Without the mid-course correction, Mariner 2 would have missed Venus entirely. After launch, Mariner 2 was on a heading that would carry it only within 238,600 miles (384,000 kilometers) of the planet's center, then speed on by, according to NASA's official Mariner 2 report. After the course correction, Mariner 2 was on a path to fly by at a much closer distance of 21,607 miles (34,773 km).

Today, such mid-course corrections are a regular part of space mission planning, though they are still critical moments since a mission's success can hinge on their results. In the decades since Mariner 2, space mission designers have achieved amazing feats in mid-course changes, including the now familar gravity assist flybys that allowed NASA to send Voyager 2 on its Grand Tour of Jupiter, Saturn, Uranus and Neptune. Many other missions have achieved such feats.

Even this week, on Sept. 3, 2026, the BepiColombo mission to Mercury performed its own mid-course event, with the mission's Mercury Transfer Module releasing its two spacecraft (one each for Europe and Japan) to begin their arrival at Mercury. The event came eight years after launch and followed a series of maneuvers, including nine planetary flybys to reach the planet.

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