Watch Spacewalk: NASA Streams Live Footage Of ISS Astronauts Outside Space Station (VIDEO)

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It's not every day viewers get to follow along as astronauts work in space. But on Tuesday, NASA streamed a live video feed as two astronauts stepped outside the International Space Station to take care of some routine work.

Broadcast on NASA TV, viewers can watch the spacewalk live (in the video above). The extravehicular activity (EVA) began shortly after 8 a.m. EDT, when Chris Cassidy of NASA and Luca Parmitano of the European Space Agency turned on the battery power in their spacesuits.

This ISS spacewalk, which is expected to last 6 1/2 hours, is the first of two set to take place in July. During the operation, Cassidy and Parmitano will primarily prepare the station for a new Russian module to be added later this year.

Though Cassidy is a seasoned spacewalker, the operation is actually the inaugural spacewalk for Parmitano, who is the first Italian astronaut to venture outside the space station.

EVA is often performed to conduct routine maintenance, but in the past, it has also been necessary in emergency situations. In May, Cassidy and another astronaut completed an emergency spacewalk outside the ISS to fix an ammonia leak.