A NASA astronaut and two cosmonauts are set to launch to the International Space Station tonight (March 25) and you can watch it live online.

NASA's Steve Swanson and cosmonauts Alexander Skvortsov and Oleg Artemyev are scheduled to fly to the station atop a Russian Soyuz spacecraft at 5:17 p.m. EDT (2117 GMT) from the Baikonur Cosmodrome in the Central Asian nation of Kazakhstan. You can watch the launch live on Space.com starting via NASA TV.

The Soyuz carrying the trio of space station crewmembers is due to dock with the orbiting outpost at 11:04 p.m. EDT, bringing the total number of space station residents up to six. They will join NASA's Rick Mastracchio, Japanese astronaut Koichi Wakata and cosmonaut Mikhail Tyurin as part of the Expedition 39 crew. [See photos from the Expedition 39 crew]

While tensions between the United States and Russia are high due Russian President Vladimir Putin's annexation of the Ukrainian region of Crimea, the launch will not be affected by the current political climate, NASA officials have said.

Crew

NASA astronaut Steve Swanson (left), Alexander Skvortsov (center) and Oleg Artemyev of Roscosmos pose for pictures in front of their Soyuz TMA-12M spacecraft. (Photo: ASA/Victor Zelentsov)

Swanson is a veteran of two space shuttle flights, but this is the first time that he'll be making an extended stay in space.

During the shuttle missions, Swanson's stints in space were mostly about building the space station, but now, he's excited about getting the chance to do more science onboard the laboratory. Swanson also thinks the six month mission will be very different from the two week missions he's flown to space before.

"I do believe my perspective will change just because really being able to live there, you really have to adapt your whole body," Swanson said. "For six months you really have to adapt and how to live there if you're comfortable doing all that."

Since the end of the space shuttle program, NASA has relied on Russian Soyuz spacecraft — like the one launching later today — to transport astronauts to and from the space station. Eventually, the space agency hopes to use private U.S. spacecraft to ferry astronauts into orbit.

Skvortsov is also a spaceflight veteran. He clocked 176 days in space when he lived and worked aboard the space station in 2010.

"I'll be able to compare the state of the International Space Station the way it is right now with what it used to be when I flew there last time, my first time," Skvortsov said during a news conference. "As far as our goals go, I'd like to maintain the station in good condition, and leave it at least not worse than the way we found it."

Artemyev is making his first trip to space, but the rookie cosmonaut has participated in two isolation experiments with Mars 500 — a simulation designed to lock volunteers away on a mock Mars mission staged on Earth. Artemyev, Swanson and Skvortsov are scheduled to return to Earth in September.

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This story was originally written for SPACE.com and has been republished with permission here. Copyright 2014 SPACE.com, a TechMediaNetwork company.