(CNN) Former NASA astronaut Mark Kelly's "next mission" is to be a US senator for Arizona.

"I care about people. I care about the state of Arizona. I care about this nation. So because of that, I've decided that I'm launching a campaign for the United States Senate," Kelly said in a video released Tuesday announcing his run as a Democratic candidate.

Kelly, 54, is the husband of former Rep. Gabby Giffords, D-Arizona, who survived a shooting in 2011. The two appeared together in Kelly's announcement video, recounting that difficult period in their lives and Giffords' rehabilitation from the gunshot wound.

"I learned a lot from being an astronaut. I learned a lot from being a pilot in the Navy. I learned a lot about solving problems from being an engineer," Kelly says in the campaign announcement video. "But what I learned from my wife is how you use policy to improve people's lives."

Since retiring from NASA, Kelly has been an advocate for gun control. Both he and his wife formed the organization now called Giffords in 2013 in order to combat gun violence after the mass shooting at the Sandy Hook elementary school in Newtown, Connecticut.

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