A U.S.-Russian crew will return to Earth from the International Space Station early Sunday morning (July 26), and you can watch their homecoming live.

A Soyuz spacecraft carrying NASA astronaut Chris Williams and Sergey Kud-Sverchkov and Sergei Mikaev of the Russian space agency Roscosmos is scheduled to undock from the orbiting lab on Sunday at 3:02 a.m. EDT (0702 GMT).

The Soyuz, known as MS-28, will land on the steppe of Kazakhstan about 3.5 hours later, at 6:26 a.m. EDT (1026 GMT). You can watch these milestones here at Space.com, courtesy of NASA.

The coverage starts today (July 25) at 9:40 a.m. EDT (1340 GMT) ahead of a change-of-command ceremony aboard the International Space Station (ISS). Kud‑Sverchkov will hand over the reins of the orbiting lab to NASA astronaut Jessica Meir, part of the transition from ISS Expedition 74 to Expedition 75 (which officially begins when Soyuz MS‑28 undocks). You can watch that live via NASA.

NASA will resume its webcast tonight at 11:10 p.m. EDT (0310 GMT on July 26) to cover crew farewells and the closing of the hatches between the ISS and Soyuz MS-28, which is expected at 11:30 p.m. EDT (0330 GMT).

Undocking coverage begins Sunday at 2:30 a.m. EDT (0630 GMT). The stream will pick up again at 5:15 a.m. EDT (0915 GMT) for deorbit and landing activities. Touchdown will occur southeast of the Kazakh city of Dzhezkazgan, according to NASA.

Soyuz MS-28 launched to the ISS on Nov. 27, which was Thanksgiving Day. That liftoff kicked off the first space mission for Williams and Mikaev and the second for Kud‑Sverchkov.

When it's all said and done, the trio will have spent 241 days in space on their current flight. They will have orbited Earth 3,856 times and traveled a total of more than 102 million miles (164 million kilometers).

After touchdown, the three spaceflyers "will fly by helicopter to Karaganda, Kazakhstan, where recovery teams are based," NASA officials wrote in a media advisory. "Williams then will return to NASA's Johnson Space Center in Houston, while Kud‑Sverchkov and Mikaev head back to their training base in Star City, Russia."

The world's most powerful solid-fuel rocket just aced its third-ever mission.

Gravity-1, a distinctively squat and stubby rocket, launched Tuesday night (July 21) from the deck of a ship stationed off the coast of Shanghai.

Liftoff occurred at 10:54 p.m. EDT (0254 GMT and 10:54 a.m. Beijing time on July 22), according to the state-run Chinese outlet Xinhua, which further reported that all nine satellites reached "their designated orbits." Details about those satellites were not provided.

Gravity-1 is operated by Orienspace, a company based in the eastern Chinese province of Shandong. The rocket stands about 100 feet (30 meters) tall — less than half the height of SpaceX's workhorse Falcon 9 vehicle.

Gravity-1 consists of three core stages and four strap-on boosters, all of which feature solid rocket motors. The launcher can haul up to 14,300 pounds (6,500 kilograms) of payload to low Earth orbit (LEO), making it the most powerful solid rocket in the world. (For comparison: The liquid-fueled Falcon 9 can deliver a maximum of 50,265 pounds, or 22,800 kg, to LEO.)

The Chinese vehicle now has three flights under its belt, all of which launched from ships at sea and achieved full mission success. Gravity-1's first two flights occurred in January 2024 and October 2025.

There won't be such a long gap before Gravity-1 flies again, if all goes to plan. The rocket is expected to launch a batch of Chinese internet satellites in the next few months, according to the state-run outlet CGTN.

And Orienspace's ambitions don't end with Gravity-1. The company is also developing Gravity-2 and Gravity-3, larger, more powerful rockets that will feature liquid-fueled core stages and solid rocket boosters.

Gravity-2 could be ready to fly by the end of the year, CGTN reported. And that vehicle will likely lift off from an ocean-based pad as well.

"Sea launch of solid-propellant rockets paves the way for future launch of liquid rockets at sea," said Gravity-1 chief designer Xu Guoguang, according to CGTN. "We are also considering other methods, such as launching from drilling platforms."

The fight continues against SpaceX's controversial South Texas land swap.

That deal, which the company made with the U.S. Fish and Wildlife Service (USFWS), gives SpaceX 727 acres (294 hectares) of public land that's currently part of the Lower Rio Grande Valley National Wildlife Refuge. In exchange, the company hands over 683 acres (276 hectares) of its territory in the area, not all of it contiguous, to the USFWS.

Last month, a coalition of conservation and tribal groups sued the USFWS over the swap, saying it degrades the refuge and violates multiple laws, including the National Wildlife Refuge System Improvement Act of 1997. And yesterday (July 20), those groups filed an emergency injunction, asking a federal judge to stop the exchange until the courts can rule on the ongoing case.

"Federal officials are racing to fork over America's public lands to one of wealthiest corporations on Earth before the courts can even weigh in," Laiken Jordahl, national public lands advocate at the Center for Biological Diversity, said in a statement yesterday (July 20).

"This refuge is one of the last places left for the public to enjoy nature in the Rio Grande Valley," Jordahl added. "Why should Texans be forced to surrender even more of their public lands to a trillion-dollar corporation? The court has to intervene now, because once these refuge lands are transferred to SpaceX, they’re gone forever."

The land set to be transferred to SpaceX is near Starbase, the manufacturing and launch hub for the company's Starship megarocket. SpaceX sees Starship as transformational; it's the biggest and most powerful launcher ever built, and it's designed to be fully and rapidly reusable.

Starship remains in the development-and-testing phase. It has flown 12 suborbital test flights to date, all of them from Starbase, and is gearing up for Flight 13 this Thursday (July 23).

These launches pose a threat to the wildlife that the 90,000-acre (36,420 hectares) refuge was established to protect, according to the Center for Biological Diversity, a conservation nonprofit based in Tucson, Arizona.

"A 2024 study found that, after one launch, every single monitored shorebird nest near the launch site suffered egg damage or loss," the organization said in yesterday's statement. "Instead of taking any enforcement actions or working with SpaceX to reduce or eliminate its harm to the refuge, the Service [USFWS] is now citing the resulting degradation as justification for handing the public land to SpaceX."

Some of the land being transferred to SpaceX is part of the Palmito Ranch Battlefield National Historic Landmark, where the final battle of the Civil War was fought. This means the swap also violates the National Historic Preservation Act, according to the Center or Biological Diversity.

The Center or Biological Diversity and its partners also take issue with how the land deal was made.

"The proposed land exchange was first made public in March, but records obtained under the Freedom of Information Act show internal agency planning began as early as April 2025," yesterday's statement reads. "In those discussions with the regional director of the Service, the agency developed 'the most expedited schedule possible' for completing a land transfer and recommended hiring additional staff to meet what they described as an 'optimum timeframe.'"

The plaintiffs in the lawsuit against the USFWS are the Center for Biological Diversity, Save RGV, the Carrizo/Comecrudo Nation of Texas, Inc., and the South Texas Environmental Justice Network.

SpaceX launched a trailblazing satellite-servicing mission today (July 21).

A Falcon 9 rocket lifted off from Florida's Cape Canaveral Space Force Station today at 5:15 p.m. EDT (2115 GMT).

SpaceX called today's launch MRV-MEV, because it's sending up a Mission Robotic Vehicle and three Mission Extension Pods (MEPs). These spacecraft will be operated by SpaceLogistics, a subsidiary of Virginia-based aerospace giant Northrop Grumman.

MRV-MEV is headed to geostationary orbit (GEO), 22,236 miles (35,786 kilometers) above Earth. At this altitude, orbital speed matches the velocity of our planet's rotation, allowing spacecraft to "hover" over the same patch of ground continuously. For this reason, GEO is a popular destination for spy, communications and weather satellites.

The new mission will work to extend the lives of such satellites. The MRV is equipped with two 10-foot-long (3 meters) robotic arms, a system developed by the U.S. Defense Advanced Research Projects Agency (DARPA) with the help of the Naval Research Laboratory. The spacecraft will use those arms to attach the MEPs — the first three ever to launch — to three separate satellites in GEO.

"Once installed, the MEP uses electric propulsion to provide orbit control and momentum unloading for a client satellite," Northrop Grumman wrote in an MEP fact sheet. "The MEP is controlled by the customer via a self-contained C- or Ku-band telemetry and command system, and [is] capable of providing up to eight years of life extension for a typical 2,000 kg satellite in GEO."

The Australian satellite operator Optus booked one of the MEPs, and Intelsat hired out the other two, according to Tech Times.

The MRV and MEPs will reach GEO separately. When it's rendezvous time, the robotic-armed spacecraft will grab an MEP and ferry it over to its client satellite, Tech Times reported. The MRV will then remain in GEO after it has installed the third MEP, waiting for other such "satellite jetpacks" to reach orbit.

In addition to installing MEPs, the MRV "can relocate, inspect, repair and upgrade spacecraft while in orbit," Northrop Grumman's website states.

"MRV includes a Northrop Grumman-developed Passive Refueling Module (PRM), the first refueling interface standard approved by the U.S. Space Force, which enables MRV to be refueled in orbit," it adds. "With advanced robotics technology and Northrop Grumman's proven experience in satellite servicing, the mission delivers an unprecedented capability and new class of system that can continuously evolve to support novel or increasingly advanced missions for our nation, making assets in space more resilient."

That "proven experience in satellite servicing" consists of two previous Northrop Grumman projects. Mission Extension Vehicle-1 (MEV-1) — the first-ever commercial satellite-servicing spacecraft — launched in October 2019 and successfully rendezvoused with its target in GEO (the communications satellite Intelsat 901) four months later. MEV-2 launched in August 2020 and docked with Intelsat 10-02 the following April.

Neither MEV-1 nor MEV-2 used Mission Extension Pods, however. Each of those previous efforts employed a single servicing craft, which made its way to the target satellite, docked and performed life-extension duties on its own.

All went according to plan during the launch: The Falcon 9's upper stage deployed the MRV 35.5 minutes after liftoff and the three MEPs at 10-minute intervals after that, according to SpaceX.

In a departure from most Falcon 9 missions, there was not a first-stage landing today.

"Due to the additional performance needed to launch these payloads to geosynchronous transfer orbit, this will be the 32nd and final flight for the Falcon 9 first stage booster supporting this mission, which previously launched CRS-24, Eutelsat HOTBIRD 13F, OneWeb 1, SES-18 and SES-19, and 27 Starlink missions," SpaceX's MRV-MEP mission description reads.

SpaceX's rocket-reuse record is 36 flights, set earlier this month during a Falcon 9 launch of the company's Starlink internet satellites.

MEV-MEP was SpaceX's second launch of the day. The company also sent 24 Starlink craft to orbit atop a Falcon 9 from California this morning.

Editor's note: This story was updated at 5:23 p.m. ET with news of successful liftoff. It was then updated again at 11:05 a.m. ET on July 22 with news of successful payload deployment, and to note DARPA's key role in this mission.

SpaceX has pushed the next launch of its Starship megarocket back a few more days.

Elon Musk's company is now targeting Thursday (July 23) for Flight 13 of Starship, the giant, fully reusable vehicle it's developing to help get people to the moon and Mars, among other spaceflight tasks.

If all goes to plan, the 408-foot-tall (124.4 meters) Starship will lift off from SpaceX's Starbase site in South Texas on Thursday during a 90-minute window that opens at 6:45 p.m. EDT (2245 GMT; 5:45 p.m. local Texas time). You can watch the action live here at Space.com, courtesy of SpaceX.

It will be the second launch attempt for Starship Flight 13. The first came last Thursday (July 16) and ended in an abort, which occurred just as the giant rocket's 33 first-stage Raptor engines were firing up.

"To be confident of a good flight, 2 Raptors will be removed & replaced. Most probable launch timing is early next week," Musk said on July 16 via X, the social media platform he owns.

SpaceX first targeted today (July 20) for Flight 13's second try. On Sunday (July 19), however, the company announced that it had pushed that date back to no earlier than Thursday.

Flight 13 will be the second launch of Starship Version 3 (V3), the latest, most advanced iteration of the megarocket. V3 is the variant that will land astronauts on the moon for NASA's Artemis program and fly SpaceX's first Mars missions, if all goes to plan.

The plan for the upcoming suborbital launch is similar to that of Flight 12, which lifted off on May 22. Starship's Super Heavy first stage will aim to steer itself back to Earth for a controlled splashdown in the Gulf of Mexico, while the Ship upper stage will do the same halfway around the world, off the coast of Western Australia.

SpaceX accomplished the latter objective on Flight 12 but not the former; Super Heavy suffered engine issues during its return to Earth and ended up hitting the Gulf waters hard.

Flight 13 will do a few new things, however. For example, it will carry 20 of SpaceX's next-gen Starlink V3 internet satellites, which have never flown to space before. SpaceX plans to build a constellation of 100,000 Starlink V3 spacecraft in low Earth orbit over the coming years, and Starship will do all of the heavy lifting.

These 20 Starlinks won't stay aloft for long, however. Since Ship is flying on a suborbital trajectory, the satellites will come back to Earth relatively quickly — about 20 minutes after deployment, according to SpaceX's Flight 13 mission description.

Starship debuted in April 2023. All of its test flights to date have been suborbital.

Half a century after first putting hardware down on Mars, NASA is looking to explore the Red Planet's skies.

On July 20, 1976, the Viking 1 lander touched down in the western reaches of Chryse Planitia (the "Golden Plain"), a large circular landform that lies 22.5 degrees north of the Martian equator.

It was the first-ever Mars landing for NASA. Viking 1, along with its twin Viking 2, went on to conduct the first fully successful mission on the Red Planet's surface. (The Soviet Union's Mars 3 probe survived its touchdown attempt on Dec. 2, 1971 but died less than two minutes later.) And those missions have left a rich and intriguing legacy.

Viking 1 and Viking 2 — which touched down in a different Red Planet region on Sept. 3, 1976 — were sent to the surface to search for signs of life on Mars. (Each mission also featured an orbiter, which studied the planet from above.)

The landers did this using three different experiments, two of which returned negative results. But the third, called Labeled Release (LR), was different. LR observed a steady stream of carbon dioxide gas coming from dirt into which it had introduced nutrients — a possible sign of microbial metabolism.

Some scientists deemed the LR results a likely life detection. But most disagreed, ascribing them to abiotic reactions and stressing that, overall, the Viking data paint a picture of a dead planet.

That disagreement illustrates one of the main legacies of the Viking program: It showed researchers that hunting for extraterrestrial life is a complicated business, and they needed to learn more about Mars before attempting the search again on the Red Planet.

NASA didn't send a surface craft to Mars for another two decades, a hiatus caused in part by the Vikings' ambiguous results and high price tag, as well as a shifting of funds to the nascent space shuttle program.

The dry spell was broken in July 1997, when the agency's Pathfinder lander touched down in Chryse Planitia, about 530 miles (850 kilometers) from Viking 1. The main goals of Pathfinder's mission were to demonstrate a new "faster, better, cheaper" method of Mars exploration, prove out a new airbag-based landing system and get a mobile robot onto the red dirt.

Pathfinder achieved all of these objectives, notching the third by deploying a small rover named Sojourner. The little wheeled robot stumbled across rounded pebbles — strong evidence that they had been exposed to flowing water.

This discovery helped shape a new NASA Mars exploration strategy, one that aims to make an informed search for alien life after "following the water." Life as we know it depends on water, so the agency built rovers designed to hunt for signs of past liquid water and potentially habitable environments.

The twin golf-cart-sized rovers Spirit and Opportunity landed in 2004, and the car-sized Curiosity followed suit in August 2012. Then came Perseverance, which landed inside Mars' Jezero Crater in February 2021.

All of these wheeled explorers found evidence of past aqueous environments. Curiosity and Perseverance — with their more extensive and sophisticated scientific payloads — delved even deeper, discovering complex organic molecules that may have been produced by life as we know it.

The two latter rovers are continuing their work; both remain active on the Red Planet. (Pathfinder and Sojourner operated for about three months; Spirit was declared dead in 2010 and Opportunity fell victim to a Mars dust storm in 2018.)

Perseverance has collected a variety of Mars samples, which NASA wants to return to Earth for detailed study. As the Vikings' experience suggests, such a level of intense scrutiny may be necessary to make a definitive detection of life on Mars, if it indeed exists. (Getting those samples home is not a foregone conclusion, however; NASA's original plan was deemed too expensive, and it's now looking into a new return strategy.)

Perseverance also carried a little robotic companion, which heralded a new phase of Red Planet exploration — the Ingenuity helicopter.

Ingenuity was a technology demonstration, designed to show that rotorcraft could effectively ply the thin Red Planet skies. (Mars' atmosphere is just 1% as dense as that of Earth at sea level.)

The $80 million mission was a rousing success. The 4-pound (1.8 kilograms) Ingenuity was expected to make just five short hops on Mars but ended up flying 72 times over the course of nearly three years of activity. (Its first flight occurred on April 19, 2021, and its last was on Jan. 18, 2024.)

So NASA aimed higher, drawing up plans for future helicopter missions that could collect valuable scientific data. And such a mission is on course to launch in 2028, if all goes according to plan: Skyfall, which will send three Ingenuity-like choppers to Mars on a nuclear-powered rocket.

"Equipped with a suite of scientific instruments, these aerial scouts will map hidden ice deposits and analyze weather patterns," NASA officials wrote in a description of Skyfall. "The mission will also demonstrate how aerial vehicles can generate wide terrain and subsurface maps to identify safe and resource-rich destinations for future American astronauts venturing to Mars."

And Skyfall could be just another step toward even more ambitious aerial exploration on the Red Planet. NASA's Jet Propulsion Laboratory in Southern California, which built and operated Ingenuity, is looking into larger, more capable Mars helicopters that could do a wider variety of work on the Red Planet.

This is all part of Viking 1's legacy. That historic touchdown on Mars half a century ago lifted exploration up — all the way into the skies of another world.