Shatner, 90, is the oldest person ever to go to space.
Actor William Shatner and his three crewmates on Blue Origin's New Shepard have returned to Earth after a 10-minute trip to space.
Shatner, 90, is the oldest person ever to go to space.
The "Star Trek" star joined Audrey Powers, Blue Origin's vice president of mission and flight operations and a former NASA flight controller and engineer; Chris Boshuizen, the co-founder of satellite company Planet Labs and a former space mission architect for NASA; and Glen de Vries, the co-founder of Medidata Solutions, a life science company.
This was Blue Origin's second crewed mission to space.
The astronauts were seen ascending the tower ahead of the historic spaceflight.
Blue Origin CEO Jeff Bezos accompanied the astronauts as they entered the shelter to prepare for ingress. Shatner was grinning as the team made the final preparations for launch.
The countdown clock was paused for approximately 30 minutes as Blue Origin teams assessed launch conditions on the ground, but the astronauts are en route to the launch pad.
Blue Origin's Jeff Bezos, who went to space himself in July, chauffeured the four astronauts to the launch tower as workers cheered.
-ABC News' Catherine Thorbecke
NASA sent a good luck tweet to William Shatner Wednesday morning ahead of the actor's trip to the edge of space.
-ABC News' Catherine Thorbecke
During the 11-minute flight, the astronauts will experience about three to four minutes of weightlessness.
They'll also travel above the Karman Line, the internationally recognized boundary separating Earth's atmosphere from space.
