China's Shenzhou 12 mission carrying three astronauts launched into orbit on Thursday morning Beijing time.

Why it matters: Astronauts Nie Haisheng, Liu Boming and Tang Hongbo are set to occupy China's new space station. This will be the country's longest crewed space mission ever and the first in almost five years.

• It marks another significant step in the space program drive of the ruling Chinese Communist Party, seen as a rival to the U.S. in space.

Details: Shenzhou 12 was launched from Jiuquan Satellite Launch Center in Jiuquan, Gansu province, China, atop its Long March 2F rocket.

The big picture: This is the "third of 11 missions" needed to complete the construction of the permanent space station, Space.com notes.

• China's government is excluded from the International Space Station program — the only space station in orbit.

What's next: The astronauts' main goal is to bring into service the Tianhe module, which was launched into orbit in April, Cmdr. Nie said, per the BBC.

• "We need to set up our new home in space and test a series of new technologies," Nie said ahead of the Shenzhou 12 launch.
• "I believe with the three of us working closely together, doing thorough and accurate operations, we can overcome our challenges. We have the confidence to complete the mission."

Editor's note: This article has been updated with new details throughout.