On Aug. 5, 2011, NASA launched the Juno spacecraft on a mission to study Jupiter, the largest planet in the solar system.

The robotic spacecraft lifted off on an Atlas V rocket from what is now Florida's Cape Canaveral Space Force Station and spent the next five years making the 1.74-billion-mile trek to Jupiter.

Next Stop, Jupiter! Launch Photos of NASA's Juno Mission

Since it arrived in Jupiter's orbit in 2016, the Juno spacecraft has taken the most amazing photos of Jupiter anyone has ever seen! But it has also taken plenty of scientific measurements to study Jupiter's composition, magnetic fields, weather patterns and more.

Why it mattered

Juno is an interesting mission. It was the first dedicated orbiter at Jupiter since NASA's prolific Galileo mission, which ended in 2003, and is the first solar-powered spacecraft to the gas giant. Indeed, each of its three 30-foot-long solar wings is as long as a semi truck to collect enough sunlight to power its systems.

But it's the science that makes Juno stand out. When Galileo orbited Jupiter, its high-gain antenna did not fully deploy, meaning the probe was never able to record detailed video of Jupiter's atmosphere as hoped. While Juno was initially built to study the inner workings of Jupiter, its camera recorded the first detailed video of the planet's clouds and atmosphere.

The Juno spacecraft's primary mission ended just 20 months after entering orbit, but NASA extended the orbiter's mission several times, most recently in 2021. That most recent extension sent Juno on multiple flybys of three of Jupiter's largest moons, Ganymede, Europa and the volcanic moon Io.

Juno's observations are already helping the science planning of future missions to Jupiter, including science targets for the European Space Agency's Jupiter Icy Moon Explorer, or JUICE, and NASA's Europa Clipper probes, which are currently en route to the giant planet.

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On Aug. 4, 2007, NASA launched its Phoenix Mars Lander on a mission to touch down on Mars.

The robotic spacecraft was designed to search for environments that could be suitable for microbial life and to study the history of water on the Red Planet. It lifted off atop a Delta II rocket at about 5:30 a.m. ET from what is now Cape Canaveral Space Force Station in Florida and spent almost 10 months making its way to Mars.

When it arrived at the Red Planet, it landed farther north than any spacecraft had ever gone before. Not only did Phoenix find water-ice, but it also found what appeared to be small globs of liquid water.

Why it mattered

The Phoenix Mars Lander was one of NASA's biggest do-overs. The lander, which touched down in the arctic plains of Mars known as Vastitas Borealis in May 2008, was designed to seek water ice below the surface and hunt organic molecules. Its origins, however, began years earlier as NASA's 2001 Mars Surveyor lander, which was canceled after the agency's Mars Polar Lander was lost during an attempted landing in 1999.

NASA repurposed the 2001 Mars lander into a Martian arctic explorer, and gave it a suite of science instruments that were improved versions of ones that rode upon the Mars Polar Lander. Its name, "Phoenix," was a reference to its "rising from the ashes" of both the dead Mars Polar Lander and the canceled Mars Surveyor.

After landing on Mars, Phoenix used a robotic arm to dig into the arctic Martian dirt to confirm the existence of subsurface ice. Perhaps the mission's biggest discovery was the existence of perchlorate, an oxidizing chemical that can be food for some microbes while toxic for others.

In November 2008, after surviving two months longer than it was designed to, the Phoenix Mars Lander fell silent, succumbing to the harsh Martian winter. Subsequent photos of the lander taken from orbit by NASA's Mars Reconnaissance Orbiter revealed that Phoenix likely suffered severe ice damage to one of its solar panels, ending its mission.

On Aug. 3, 2004, NASA launched the MESSENGER spacecraft on a historic first mission to orbit the planet Mercury. The spacecraft's name stands for the MErcury Surface, Space ENvironment, GEochemistry and Ranging mission.

It blasted off on a Delta II rocket that launched from Cape Canaveral Space Force Station in Florida at 6:15 a.m. Eastern Time and spent the next six and a half years making its way to Mercury's orbit. Because Mercury is so close to the sun, a spacecraft travelling toward the planet speeds up as the sun's gravity pulls it in.

In order to slow down enough to avoid falling into the sun, MESSENGER utilized the gravitational pull of Venus and Mercury with multiple flybys along the way. It made 15 trips around the sun before it finally arrived in Mercury's orbit in 2011.

Why it mattered

Mercury is an odd planet. It is close to the sun, yet holds the promise of water ice on its surface. It completes one orbit every 88 days. But it can be a devil of a planet to reach with a spacecraft.

The launch of NASA's MESSENGER spacecraft was the first step to bring the rocky, craggy Mercury within tantalizing reach of scientists hoping for an upclose look at the planet. The spacecraft made some surprising discoveries, revealing that Mercury's core is huge — roughly 85% of its radius (Earth's core is only 50% of its own radius). The planet is also very flat, with less elevation changes than those found on Earth's moon and Mars. MESSENGER's greatest finds may have been extremely "radar-bright" deposits in craters at Mercury's poles, which are in permanent darkness and may hold pockets of water ice.

MESSENGER's primary mission at Mercury ended in 2012 and its mission was extended twice. In 2015, NASA ended the MESSENGER mission by crashing the probe into Mercury.

A new spacecraft is now headed for Mercury. The BepiColombo mission, a joint project by Japan and the European Space Agency, launched two different orbiters to Mercury in 2018 and is due to arrive at the planet in November.

On Aug. 2, 1971, a lunar liftoff was televised for the first time. Apollo 15 astronauts David Scott and James Irwin spent three days on the moon before departing in the lunar module, named "Falcon."

An RCA TV camera was mounted onto their lunar rover, which Scott parked about 300 feet away with the camera pointed at Falcon. Flight controllers in Mission Control Houston had the option to move the camera, but because of some technical difficulties, they opted to leave the camera pointed in the same direction during liftoff. from the moon. Following a quick pop and a bunch of sparks, Falcon quickly disappeared from sight. Shortly afterward, Falcon joined the command module "Endeavour," and Apollo 15 began its journey back to Earth.

• Apollo 15 in Photos: A Moon Landing and the 1st Lunar Car for Astronauts

The Apollo 15 mission launched to the moon on July 26, 1971. The mission was commanded by David Scott, with James Irwin as lunar module pilot. Astronaut Al Worden served as command module pilot and remained aboard Endeavour as Scott and Irwin explored the moon's surface. The Apollo 15's Falcon lunar lander touched down on the moon on July 30. Orwin and Scott performed three moonwalks and test drove NASA's new lunar rover before lifting off on Aug. 2.

The Apollo 15 crew remained in lunar orbit until Aug. 4, when they departed for Earth. The mission ended with a splashdown landing in the Pacific Ocean on Aug. 7.

Why it mattered

When Apollo 11 astronauts Neil Armstrong and Buzz Aldrin first walked on the moon, their first lunar steps were broadcast to the world live. But their liftoff, not so much.

But capturing a liftoff live from the moon was the next logical step to chronicle NASA's lunar exploration in real-time. The TV camera mounted on Apollo 15 Lunar Roving Vehicle, which also made a moon debut on this mission, and was remote controlled by flight controllers on Earth, pioneering a process that is commonplace today on the International Space Station. It also allowed engineers to see how a lunar module actually behaved during liftoff in the moon's one-sixth gravity.

That legacy of live video from the moon took center stage in April 2026 during NASA's Artemis II mission, which sent the first astronaut to visit the moon since the Apollo 17 mission in 1972. The Artemis II Orion spacecraft was covered in cameras, both inside and out, allowing NASA to livestream the entire voyage to the moon and back, nonstop.

On Aug. 1, 1968, NASA canceled the production of its Saturn V moon rocket. At the time, the giant rocket was the only launch vehicle to have ever carried astronauts beyond low-Earth orbit, and it was then the largest, most powerful rocket ever.

NASA built 15 of these rockets but only flew 13 of them. When NASA made the decision to stop building the Saturn V, it was almost a year before Apollo 11 astronauts would walk on the moon for the first time.

• 10 Surprising Facts About NASA's Mighty Saturn V Moon Rocket

A federal budget deficit and the rising costs of the Vietnam War led Congress to slash nearly three-quarters of the funding that President Lyndon Johnson had allotted for the Apollo program.

The last Saturn V launched in 1973, and it was originally supposed to send Apollo 18 to the moon. However, that mission was canceled, and that Saturn V launched the Skylab space station instead.

Why it mattered

From start to finish, NASA spent a reported $9.4 billion on the Saturn family of rockets (which would be an estimated $118 billion in today's dollars) to develop the Saturn V. That includes the Saturn I and Saturn IB blocks. But the decision to shut production down in 1968 over those costs spelled the end of NASA's Apollo program to send astronauts to the moon a year before the Apollo 11 astronauts even walked on the moon in 1969.

Without a steady supply of heavy-lift rockets (the Saturn V was the most powerful of its day), NASA only had a limited number of moonshots left. The final Saturn V rocket to carry astronauts sent the Apollo 17 astronauts to the moon in 1972. The Skylab mission flew a year later, with the final Saturn IB rocket launching an Apollo command module on the Apollo-Soyuz flight in 1975.

It would not be until 2022, when NASA launched the first Space Launch System on the Artemis I mission, that the space agency had another megarocket to rival the Saturn V. In April 2026, that new rocket launched NASA's Artemis II astronauts around the moon.

SpaceX has developed a new megarocket that is even more powerful than the Saturn V, with its Starship and Super Heavy booster.

On July 31, 1971, Apollo 15 astronauts drove on the moon for the first time.

David Scott, the commander of Apollo 15, and James Irwin, the lunar module pilot explored the moon for three days by driving around in the Lunar Roving Vehicle. Apollo 15 command module pilot Al Worden remained in orbit around the moon. This moon buggy was folded up and stowed inside the lunar module and deployed after landing. Unpacked, it measured about 10 feet long, 7 feet wide and 45 inches high.

The lunar rover could travel up to 8.6 miles per hour and allowed the astronauts to venture farther from their landing site than previous Apollo astronauts could. For their first drive, Scott and Irwin went to Elbow Crater to gather samples and take photos. Throughout their stay on the moon, they drove more than 17 miles.

• Apollo 15 in Photos: A Moon Landing and the 1st Lunar Car for Astronauts

The Apollo 15 mission launched to the moon on July 26, 1971. The mission landed on July 30, with Scott and Irwin ultimately performing three moonwalks in addition to their lunar rover test drive. The Apollo 15 crew left the moon's surface on Aug. 2 and left lunar orbit on Aug. 4. They returned to Earth on Aug. 7, splashing down in the Pacific Ocean.

Why it mattered

Apollo 15's moon rover made space history as the first human-driven rover on the moon, let alone another world entirely.

While developing the rover, NASA had to wrangle many issues at once. How do you build a rover light enough to land on the moon with the Apollo 15 lunar lander? How do you make it compact as well?

• Driving on the Moon: Photos of NASA's Lunar Cars

The result was an aluminum, foldable moon car built by Boeing and powered by batteries that could carry up to 1,080 pounds (490 kg) of cargo — about twice its own weight — while carrying two astronauts. The rover design flew on Apollo 15, Apollo 16 and Apollo 17. Those three rovers are still on the lunar surface awaiting fresh batteries.

Today, NASA is looking to new companies to build unpressurized rovers like the Lunar Roving Vehicle, as well as pressurized vehicles that would allow crews to drive without a spacesuit on. Those rovers will be a critical asset for Artemis astronauts as they build a permanent moon base, NASA has said.

On July 30, 1610, the famous astronomer Galileo Galilei became the first to observe rings around the planet Saturn.

Shortly after the telescope was invented in 1608, Galileo peered out into the solar system and saw the amazing ring system. At first he didn't actually think they were rings.

Instead, Galileo thought Saturn might have planetary "love handles" that gave it a weird shape. He also wondered if perhaps he was looking at two very large moons on either side of the planet. It wasn't until 1659 that another astronomer named Christiaan Huygens figured out that these weird features were actually Saturn's rings.

Why it mattered

Today, we may take Saturn's rings for granted. After all, it IS known as the "ringed planet" and the jewel of our solar system. But there was a time when we didn't know planets had rings at all, and that's where Galileo's discovery came in.

The telescope was a brand new technology, just two years old, when Galileo took it from a seafaring and distance tool and turned it into an essential item for astronomy. It helped him discover the major moons of Jupiter (we call them the Galilean moons for a reason) and also Saturn's rings. In time, astronomers discovered rings around other large planets in our solar system (Jupiter has them, and Uranus, too), revealing them to be made up of tiny pieces of what may have been torn apart moons.

The study of Saturn's rings has allowed astronomers to see the raw materials of the early solar system. They're made mostly of water ice and shaped by so-called shepherd moons, tiny satellites that orbit Saturn in between ring bands. Saturn's rings even have "kittens," distinct formations scientists are only now starting to understand.

NASA's Pioneer 11 passed through Saturn's ring plane in 1979, with the Voyager 1 and Voyager 2 probes visiting in the 1980s. The Cassini spacecraft was the first to orbit Saturn, ultimately passing through the rings several times in 2017 before ending its mission in a "grand finale" with a crash into Saturn itself.

On July 29, 1982, the Salyut 6 space station fell out of space and safely burned up in Earth's atmosphere along the way.

Salyut 6 was the eighth space station the Soviet Union had built for its Salyut program. It spent almost five years in orbit and supported five different crewed cosmonaut missions. While aboard Salyut 6, those cosmonauts made astronomical observations and studied the effects of spaceflight on the human body.

Though the aging space station was still considered fully functional in 1982, a mold problem in the crew quarters led the Soviets to abandon the orbiting lab. They intentionally sent it plunging toward Earth, where it would burn up in the atmosphere before hitting the ground.

Why it mattered

Launched in 1977, Salyut 6 marked an evolution of space station design for the then-Soviet Union. It was the USSR's first to have two docking ports, which allowed longer missions by Salyut cosmonauts since an uncrewed Progress cargo ship could periodically resupply a crew.

That second docking port could also be used by a visiting crew, flying on a short trip to Salyut 6 on a new Soyuz and returning home on the host crew's original capsule. (The U.S. Skylab station also had two docking ports.)

• Top 10 Soviet and Russian Space Missions

Salyut 6 also had an airlock for spacewalks and has been hailed as the first "second generation" space station. The longest mission to Salyut 6 lasted 185 days, a record at the time in 1981.

The advancements demonstrated on Salyut 6 can be seen in routine use on the International Space Station today. The ISS has multiple docking ports for visiting crews, crew handovers and automated cargo ships. It has multiple airlocks for spacewalks (depending on if they are U.S. or Russian-led) and regularly hosted missions of at least 6 months in duration. The longest mission to the ISS by an American was 371 days, a record set in 2023 by NASA astronaut Frank Rubio.

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On July 28, 1851, the first-ever photo of a total solar eclipse was recorded by a Prussian daguerreotypist named Johann Julius Friedrich Berkowski.

Daguerreotypy is an old photographic process that uses silver-plated copper treated with chemical fumes that make it light-sensitive. Previous attempts to take photos of solar eclipses failed to show the contrast between the sun's corona and the dark disk of the moon.

Using a small, 6-centimeter telescope, Berkowski captured an 84-second exposure starting right after the moon moved completely in front of the sun.

• The Evolution of Solar Eclipse Photography in Photos

Why it mattered

Until Berkowski, total solar eclipses were something people saw once and never again. The ability to document a solar eclipse visually opened the door for scientists to study the solar event - and the sun - like never before. (Not to mention, make a rare astronomical phenomenon more accessible to people unable to see it.)

To be clear, many photographers did try to capture solar eclipses before Berkowski, but those attempts were often overexposed or underexposed. But Berkowski's daguerreotype was detailed enough that in 2005, 154 years, it was hailed as the first correctly exposed image of the sun's corona, the super-hot outer atmosphere of the sun that is visible around the moon during totality.

Today, more than 170 years later, the advent of digital cameras — and even smartphones — has put the ability to photograph a solar eclipse literally in the palm of our hands. Our Editor-in-Chief Tariq Malik has seen two total solar eclipses (in 2017 and 2024), and managed to snap the 2024 eclipse with a smartphone with no training at all (and a bit of luck).

By the way, the next total solar eclipse is coming on Aug. 12 and will be visible across parts of Greenand, Iceland and Spain. To find out how you can capture a totality photo of your own during a total solar eclipse, check out our solar eclipse photography guide and gear up with our best solar eclipse photography equipmetnt for 2026.

And DON'T FORGET! If you're observing a solar eclipse on your own, you'll need eclipse glasses for safety.

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On July 27, 1962, two Russian cosmonauts boarded a Soviet airliner and experienced weightlessness without going to space. This was the first time cosmonauts completed zero-G training on an airplane.

The Tupolev Tu-104 was a type of jetliner originally designed to transport 50 passengers. It was modified to accommodate cosmonauts who needed to train in an environment that simulated weightlessness. By flying in a parabolic arc, passengers could experience 6 to 25 seconds of weightlessness on each maneuver.

Cosmonauts Andriyan Nikolayev and Pavel Popovich were on this flight to prepare for their upcoming orbital missions Vostok 3 and Vostok 4.

Why it mattered

Human spaceflight was barely a year old in July 1962, so methods of training cosmonauts (and astronauts) were still in development. In the early days of the Space Age, the effects of weightlessness on the human body — including basic functions like eating and using the bathroom — were still being understood, so the more realistic training could be the better.

For Nikilayev and Popovich, this training was vital. Their Vostok 3 and Vostok 4 missions flew at the same time, marking the first-ever dual spacefligth of two crewed craft (they were single-person capsules). Vostok 2 lasted nearly four days — something NASA would not beat until the Gemini program in 1965 — while Vostok 4 was a nearly three-day flight. The two spacecraft flew within 4 miles of each other during their missions.

Today, NASA and Russia's Federal Space Agency (Roscosmos) still train astronauts and cosmonauts on modified jets that simulate weightlessness by flying parbolic flights. You can even buy a ticket to try it yourself through commercial companies like Zero Gravity Corporation, which also flies science flights for NASA.

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