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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LINK, the satellite sent to boost the orbit of NASA's Swift Observatory, may have had to give up on its mission, but LINK's manufacturer and operator Katalyst Space hasn't completely abandoned the spacecraft to its cosmic demise.

NASA called off LINK's mission to rendezvous with its Neil Gehrels Swift Observatory when the specialized probe encountered a thruster control issue. LINK was delivered to orbit on July 3, aboard an air-launched Northrop Grumman Pegasus XL rocket, but began to spin uncontrollably about three weeks after reaching space. Swift's orbit began decaying faster than expected last year, due to increased solar activity, and LINK was designed to rendezvous with Swift, grapple it, and then raise the observatory to a more stable altitude.

LINK's Swift Boost mission was considered a "Hail Mary" attempt from its onset. NASA's discovery of Swift's swiftly decaying orbit meant the Arizona-based Katalyst had less than a year to design, manufacture and test LINK before needing to launch. Now, with both of their missions on the short-track for destruction, NASA and Katalyst are left both trying to get the most out of their spacecraft with the time each has left.

LINK's failure means Swift is destined to burn up in Earth's atmosphere before the end of the year, and LINK itself is expected to fall to the same fate within just the next few weeks. But the probe's inability to save Swift hasn't stopped Katalyst from getting as much data from LINK as it can. Though a closer rendezvous is no longer in the cards, the spacecraft managed to successfully fire all three of its electric propulsion thrusters and adjust its orbit to fly within 7.5 to 9 miles (12 to 15 kilometers) of Swift. Katalyst was also able to deploy all three of LINK's robotic arms, which would have been used to grapple Swift for its orbital adjustment.

Swift launched in November 2004, and has been studying high-energy phenomena like gamma-ray bursts, supernovas, black-hole ejections and fast radio bursts across the universe for more than 20 years. Despite its impending demise, two of Swift's three science instruments — its X-ray Telescope (XRT) and Ultraviolet/Optical Telescope (UVOT) — were turned back on in late August after being shut down in February to minimize atmospheric drag on the spacecraft in anticipation of LINK's now defunct orbital boost efforts.

With the option for LINK to raise Swift's orbit now off the table, Katalyst and NASA are working to perform whatever technology demonstrations are possible aboard the spacecraft, in the hopes the technology can be used to service other satellites on missions in the future.

Three of NASA's Artemis II astronauts are starting off the school year with new assignments.

Artemis II commander Reid Wiseman and pilot Victor Glover, both NASA astronauts, will transition into "emeritus status" in September, the space agency announced on Wednesday (Sept. 9). Meanwhile, Canadian mission specialist Jeremy Hansen shared a video on X on Tuesday (Sept. 8) concerning his already-announced transfer from active duty to reserve status in the Canadian military.

The fourth Artemis II astronaut, NASA mission specialist Christina Koch, appears to still be on active duty, as no announcements have been made saying otherwise.

The Artemis II quartet flew around the moon in April, becoming the first people to go beyond low Earth orbit since 1972. The historic journey was widely expected to be the last step in active astronaut duty for at least some of the mission's four astronauts, especially Hansen, who had waited for a flight assignment for 17 years in part due to how Canadian Space Agency funding is allocated. (Robotics provided by the CSA form a minority share of international space partnerships with NASA, and astronaut flight rates are tied to funding.)

The Artemis II astronauts made a series of public appearances together this summer, culminating on Aug. 28 when President Trump awarded them the Congressional Space Medal of Honor. Hansen was only the second non-American to receive the award, which had previously been given to just 30 astronauts total.

While NASA's Wednesday announcement about Glover and Wiseman did not explicitly state that the duo are exiting active astronaut duty, their new role is described as allowing the astronauts to assist NASA as consultants and "individuals with a high degree of technical and professional knowledge," while allowing them to do other things.

The two astronauts are expected to help NASA plan future Artemis program missions. "I'm grateful they will continue sharing what they learned with our astronauts, flight controllers and engineers as we prepare for Artemis III in 2027 and the missions that follow," NASA administrator Jared Isaacman said in the statement.

Glover, who also retired from the U.S. Navy recently, will now assume a full-time role at his alma mater, California Polytechnic State University in San Luis Obispo, which has aerospace and space programs. The news was announced by the university on Wednesday, but the position took effect on Sept. 1. Glover will be an administrative leader providing advice to senior leadership on education, research and workforce strategies, according to Cal Poly.

"The most meaningful moments of my NASA career were supporting astronauts and their families through missions, and mentoring interns and new hires as they began their own journeys in technical and public service," Glover wrote Wednesday in a post on X about the career change.

Wiseman did not share any specific updates about his career plans on social media. The astronaut also exited active astronaut duty temporarily between 2020 and 2022 when he was chief of the astronaut office for NASA, a role that precludes flying in space as the chief is involved in flight assignments. Wiseman left that role and resumed active astronaut duty before being assigned to Artemis 2, which occurred shortly before the public announcement of the mission's crew in April 2023.

"NASA gave me tremendous responsibility, supported me through two space missions — and my time as chief astronaut — and was always there for my family when we needed it most," Wiseman said in the NASA statement about his career change. "I'm thrilled to continue serving future missions and programs through the emeritus program."

Hansen's Artemis 2 duties officially concluded on Sept. 2, according to his X account, and the astronaut — who has been based out of Houston since 2009 — posted a new video of himself Wednesday walking in the woods in Canada. Hansen said he has retired as a colonel with the Royal Canadian Air Force and is now a reservist working with 3 Canadian Space Division, which is essentially Canada's Space Force.

"The intention of that is to continue to serve Canada and government — the Canadian Space Agency — when it makes sense, to help us take advantage of some of the extraordinary opportunities that are before us right now," Hansen said in the video, adding that he will divulge more details about that work shortly.

Hansen also said he accepted a role as honorary national president with the Canadian military's Air Cadet League of Canada, which the astronaut has often said helped equip him with both flying and leadership skills when Hansen was growing up.

Additionally, Hansen pledged to "continue to share the moon joy" both as an individual and with his crew. For example, he recently joined a Canadian keynote-speakers bureau in which he plans to speak about how to accomplish personal "moonshots." In October, Hansen will also co-release "Earthrise: A Canadian Astronaut's Journey Into Deep Space" (HarperCollins Publishers, 2026) — a book that discusses his career and Artemis 2 — which he co-wrote with Canadian author John Larsen.

SpaceX launched a secret mission for the U.S. Space Force today (Sept. 10) from California's central coast.

A Falcon 9 rocket lifted off from Vandenberg Space Force Base today at 11:42 a.m. EDT (1542 GMT; 8:42 a.m. local time), kicking off a mission called USSF-153.

The rocket's first stage came back to Earth about 8.5 minutes later, landing in the Pacific Ocean atop the SpaceX drone ship "Of Course I Still Love You." It was the 27th flight for this particular booster, which is designated B1801. The record for a SpaceX rocket is 37, set last month during a launch of the company's Starlink internet satellites.

USSF-153 is a classified mission, so little is known about its payloads — what they are or where exactly they're headed. We didn't get much clarity from the webcast, which ended shortly after the Falcon 9's first stage landed.

However, the location of that touchdown provided some potentially useful information about USSF-153, according to NextSpaceflight.com.

The mission might be carrying "a batch of classified LEO [low Earth orbit] satellites for a U.S. government entity based on SpaceX's Starshield satellite bus, based on locations of rocket stage drop zones being exact fits with previous Starlink Group 15 launches," the outlet wrote.

"Starshield leverages SpaceX's Starlink technology and launch capability to support national security efforts," SpaceX wrote in a description of the Starshield program.

Today's launch was the 104th Falcon 9 mission of 2026. Eighty of the rocket's flights this year have been dedicated to building out the Starlink megaconstellation, which currently consists of more than 11,000 active spacecraft.

Editor's note: This story was updated at 11:55 a.m. ET on Sept. 10 with news of successful launch and rocket landing.

Celebrations of Star Trek's 60th anniversary made it all the way to the final frontier.

Among the science and supplies delivered to the International Space Station (ISS) for European Space Agency (ESA) astronaut Sophie Adenot's mission on orbit was a small piece of memorabilia to honor one of the most influential pop culture phenomena that has continually called for humanity to turn its gaze to the stars. Adenot carried a small Starfleet badge from one of Star Trek's newest series, Strange New Worlds, which she wore during a video posted by ESA and Star Trek.

"It's a small object, but it carries something bigger: sixty years of a story that taught us to dream about exploring together," ESA said in a separate post picturing the golden badge floating in front of the station's large Cupola windows. "From the crew of the USS Enterprise to the crews on the International Space Station, the mission hasn't really changed. Explore. Discover. Do it together," the post says.

Adenot launched to the ISS aboard a SpaceX Dragon capsule on NASA's Crew-12 mission to the orbital lab on Feb. 13, and is serving as flight engineer for ISS Expedition 75. It's her first launch to space, and is set to wrap up soon, pending the launch and arrival of SpaceX's next Dragon spacecraft carrying the astronauts of NASA's Crew-13 mission, expected within just a few weeks.

In Adenot's video, she is seen donning the Starfleet badge on her ESA-issue ISS shirt, floating in ESA's Columbus laboratory module. "For me, exploration and science are about curiosity and cooperation, daring to go a little farther together, learning from what we discover and build, and turning that knowledge into a better future for everyone," she said.

Star Trek, too, has resonated with similar themes. Since its premiere on Sept. 8, 1966, the show has told stories that place social issues and cultural conflicts front and center in a way that 'demonstrates the best traits of humanity. It depicts, in its creator Gene Roddenberry's view, an idyllic version of humanity he believed was truly achievable through the act of simply accepting one another.

"The whole show was an attempt to say that humanity will reach maturity and wisdom on the day that it begins not just to tolerate, but to take a special delight in differences in ideas and differences in life forms," Roddenberry said in the 1976 album The Star Trek Philosophy. "If we cannot learn to actually enjoy those small differences — take a positive delight in those small differences between our own kind — here on this planet, then we do not deserve to go out into space and meet the diversity that is almost certainly out there."

ESA celebrated that philosophy, and the potential it holds for humanity. "Science fiction imagines the future. We build it," ESA's post said. "From the crew of the USS Enterprise to the crews on the International Space Station, the mission hasn't really changed. Explore. Discover. Do it together."