By Richard Pérez-Peña, Kenneth Chang and Andrew E. Kramer

New York Times News Service

As they hurtled toward space faster than a rifle bullet, an American astronaut and a Russian cosmonaut were forced to make a harrowing but safe emergency landing Thursday when the rocket carrying the two men and hundreds of tons of explosive fuel failed less than two minutes after liftoff.

The Russian-built Soyuz capsule parachuted to Earth about 12 to 15 miles outside Zhezqazghan, a small city in central Kazakhstan. Neither crew member — Nick Hague of the United States or Alexei Ovchinin of Russia — was injured, the Russian and U.S. space agencies said, and the two were rescued within an hour of their landing.

The launch failure does not put the three astronauts aboard the International Space Station in any danger. They have plenty of food, water, air and other supplies. The station is a laboratory for science experiments that cannot be conducted in the pull of gravity, and NASA is using it as a testing ground for technologies for longer, farther voyages to the moon and Mars.

It could set off a sequence of events that leads in January to the station being emptied of crew for the first time in 18 years.

The launch mishap occurred at a moment of transition in U.S.-Russian space relations, and during the first visit of NASA’s administrator, Jim Bridenstine, with his Russian counterparts. With the United States contemplating an end to the space station’s mission a decade from now, both nations sought to emphasize that they would cooperate in investigating what caused the rocket to fail.

According to a Russian space official cited by Interfax, “the emergency occurred 119 seconds into the flight, during the separation of the side boosters of the first stage from the central booster of the second stage.” The second-stage booster rocket shut down.

Roscosmos, the Russian space agency, anticipating a successful launch, had posted a glowing description of the flight on its Facebook page when the problems occurred.

“The crew is returning to Earth in a ballistic descent mode,” NASA wrote in a tweet, meaning that the capsule was falling without propulsion and that its direction was determined only by the craft’s momentum, later braked by a parachute landing. The angle of the capsule’s descent is normally carefully calibrated so it does not overheat and threaten the crew’s safety.

Forty-two minutes after liftoff, NASA tweeted that the Soyuz capsule had landed on Earth. A search team was dispatched and soon afterward, NASA added, the rescuers reported that the Soyuz crew were “in good condition.”

Dmitry Peskov, the Kremlin spokesman, told journalists in Moscow: “Thank God the cosmonauts are alive. This is the main thing.”

The Russian space agency tweeted a picture of the two men sitting and speaking with Dmitry O. Rogozin, head of the Russian agency.

NASA posted a picture on Twitter of the astronauts with their families at the Baiknour in Kazakhstan where their ill-fated voyage began.

Soon after the incident, Russia announced it was suspending missions to the International Space Station until the cause of the failure had been determined.

The three astronauts on the space station — Alexander Gerst of the European Space Agency, Serena M. Auñón-Chancellor of NASA, and Sergey Prokopyev of Russia — arrived in June and had been scheduled to return in December. Their stay is likely to be extended as the Soyuz is the only vehicle available to take people to and from space.

Soyuz capsules are rated to remain in orbit only about seven months. The one capsule docked now — and the crew’s ride home — has been there since June. Although the station is well stocked, the seven-month limitation means the astronauts would likely have to leave in early January.

“There’s a little bit of margin on the other side of that,” Kenneth Todd, the operations integration manager for the space station at NASA, said during a news conference. “But not a whole lot of margin.”

The Soyuz docked is at the center of an earlier incident in August when a leak was discovered in the capsule. The unexplained hole appeared to have been deliberately drilled, leading to wild speculation in Russian media that NASA astronauts committed sabotage.

The meeting of Rogozin and Bridenstine at the launch marked the start of talks on the future of the space relationship. The talks could culminate in a commitment for what NASA has proposed as a next step in human spaceflight, a station called Lunar Gateway to orbit the moon. Or it could end with the two countries headed in different directions.