St. Louis astronaut taking his 7th spacewalk

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INTERNATIONAL SPACE STATION (KMOX) - St. Ann native Bob Behnken is taking part in his seventh spacewalk Friday, joining crewmate Chris Cassidy on a six-to-eight hour excursion to replace batteries on the International Space Station. 

Astronaut Mike Fincke who's taken nine spacewalks, tells KMOX the batteries are 5-feet long and weigh 500 pounds on earth. They're weightless in orbit, but Fincke says, installing them is still difficult.

"If you start pushing it and you want to slow it down it requires a lot of work," Fincke says. "You have to be very careful moving heavy things ... Mass has its consequences. You have to be careful so you don't lose your grip or that things float away." 

Related: St. Louis native says he slept well during first night in SpaceX spacecraft

Today marks two weeks since @AstroBehnken and @Astro_Doug launched to the space station! Earlier this week, the duo shared some differences between their #LaunchAmerica mission and space shuttle flights.Learn more about the crew and their mission: https://t.co/jOK0EMqUMN pic.twitter.com/adfiMxBlJp

— Intl. Space Station (@Space_Station) June 13, 2020

Fincke says a spacewalk is a 'carefully coordinated ballet' where you have to be aware of every move.

"We can learn to have the stamina and to be very careful and ergonomically, we don't use up a lot of energy when we move. Eventually we get this gracefulness that doesn't take up too much energy." He adds, "They go by really quickly when you're in the groove getting the job done."

Even though it's Behnken's seventh spacewalk, Fincke is sure he'll take a few seconds to appreciate where he is.

"He knows now and then just to take a few seconds and look at the cosmos. The stars are all out there," Fincke says. "They're not twinkling and you can see the rest of the universe. The only thing between you and the rest of the universe is this little glass faceplate that is keeping your air in and the rest of the universe out."

Fincke calls walking in space, "A humbling, amazing, scary, wonderful and awesome experience."

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