Airing Friday at 8 p.m. Eastern/5 p.m. Pacific, "Live From Space" will originate from the International Space Station with American astronaut Rick Mastracchio and Koichi Wakata, who's Japanese, as on-board correspondents. (It will air on National Geographic Channel in 170 countries in all, on Channel 4 in the United Kingdom and on the Spanish-language Nat Geo MUNDO network.)
Veteran reporter Soledad O'Brien will anchor from NASA Mission Control in Houston.
O'Brien said she's excited about the special, and particularly happy to be hosting "Live From Space" from a comfortable distance.
"The moment I understood that I would be firmly on the ground and THEY would be firmly in space, and we would have an opportunity to do something that hasn't been done before, I was in," said O'Brien as she prepared to leave for Houston where, besides serving as a producer, she will preside alongside astronaut Mike Massimino, who has logged quite a few miles in space.
One of the many challenges of mounting a TV special like this: Its remote "studio" is 250 miles above the Earth's surface and hurtling through space at 17,500 miles per hour. During the span of the special, the space station (and viewers) will circle the planet and begin a second orbit, with dazzling dawn-to-dusk-to-nightscape views promised.
But staying connected won't be a snap. To fill any gaps when TV contact with the space station might be interrupted, and to supplement the special with background perspective, the on-site astronauts have been taping features for inclusion in the program.
"They are phenomenal 'field reporters,'" said O'Brien, "especially when you think of everything they have to do when they're NOT shooting video."
One of the more dramatic taped segments: Last summer's near-drowning of Italian astronaut Luca Parmitano as his helmet filled with a half-gallon of water during a spacewalk to do repair work on the craft. He barely made it back inside the station alive. Despite Parmitano's calm demeanor, the sequence is riveting, even alarming, as a reminder of the risks of space travel - and may recall for some viewers the recent outer-space thriller "Gravity."
"Sometimes the reality is more compelling than a movie version has to be," said O'Brien.
But most of "Live From Space" is meant to be live, including a guided tour of the station, which spans the area of a football field and weighs nearly 1 million pounds. Besides Mastracchio and Wakata, the station's only other resident currently is Russia's Mikhail Tyurin. But the complex has more livable room than a conventional six-bedroom house, with two bathrooms, a gym and a 360-degree bay window that viewers will be able to peer out of.
The astronauts will conduct never-before-broadcast experiments that demonstrate the scientific purpose of the station.
And they'll address some up-close-and-personal issues, such as what it's like living in microgravity for months, how they're able to sleep upside down, how they maintain personal hygiene and how they use the toilet.
Viewers are welcome to get on board - virtually - through Instagram by posting photos, videos and questions.
In many ways, "Live From Space" will be a typical project for O'Brien (who has tackled lots of live telecasts for NBC News, CNN and elsewhere). On Thursday, she prepared for a routine run-through of the broadcast.
But there will be differences aplenty that set this show apart.
"What is the best way to navigate an interview with two guys who are 250 miles up and speeding through space?" O'Brien wondered, voicing just one of them.