Fifty years after the first human walked in space, scientific research is routinely being conducted at an international space station and private companies are getting deeper into the game.
"We're doing a lot of research related to trying to get humans into outer space … get ready for the Mars missions," director of the International Space Station, Sam Scimemi, said in an interview with "Closing Bell" on Thursday.
"We're also doing a lot of development in the commercial world, trying to get commercial industry to utilize the space station."
In fact, NASA has already shifted some responsibility over to private companies like Space X and Boeing in transporting astronauts to and from the space station, said Phil McAlister, the director of NASA's commercial spaceflight development division.
"It's been a really great thing for NASA and for industry because this partnership, we sort of take the best of both to get our astronauts back up to space," he said.
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On Wednesday, the U.S. House of Representatives approved $18.5 billion in funding for NASA. Scimemi, McAlister and NASA astronaut Joseph Acaba rang the closing bell at the New York Stock Exchange, along with representatives from Boeing and Space X.
Unlike the early days of space travel, when astronauts were more like pilots, these days they are scientists first and foremost, Acaba said.
When on the space station, astronauts will do research and maintain the structure.
"In a six-month period, you may work on over 100 different scientific experiments. Half of them are looking at getting us to Mars and beyond and the other half are trying to improve life here on Earth," he said.
Right now, NASA is conducting a twin study, with Scott Kelly at the space station and his twin Mark on Earth. The so-called investigations will look into the subtle effects and changes that may occur in spaceflight.
Kelly, along with a Russian cosmonaut, is expected to stay at the station for a year.
Scimemi described the agency's relationship with Russia "excellent" and called the country a very reliable partner.
As for China's efforts to explore space, Scimemi was positive.
"It's very good to see many countries, including China, to be interested in going into space with humans," he said. "It's better for humanity to be able to do that."'