Retired NASA astronaut Mark Kelly announced he is running for U.S. Senate for Arizona in 2020 with a campaign video posted on his Twitter account early Tuesday morning.

In the tweet Kelly, a Democrat, called it his "next mission."

"You know, it becomes pretty obvious pretty early when you get into space that we're all kind of in this together," Kelly says in the video.

Kelly says Arizonans are facing "incredibly challenging issues here in the years to come." Kelly lists access to affordable healthcare, stagnation of wages, job growth, the economy and even drought as the climate warms as the issues Arizona is facing.

"Solving some of the hardest problems requires one thing... and that's teamwork," he says.

Kelly says corporate money, gerrymandering, partisanship and polarization have "ruined our politics and it's divided us." 

"I care about people, I care about the state of Arizona," I care about this nation," he says.

Kelly is the husband of former Democratic congresswoman Gabrielle Giffords. Giffords makes an appearance in the video with Kelly who says he learned from her how "you use policy to improve people's lives."

"You nearly lost your life serving your country," Kelly says to Giffords. "But what do you do when bad things happen?"

"Move ahead," Giffords says.

Kelly says "we've seen this retreat from science and data and facts."

"If we don't take these issues seriously we can't solve these problems," Kelly says. "We're going to need to bring people together from all parts of the state and all walks of life."

The campaign video ends with both Kelly and Giffords saying "full speed ahead!"

Kelly is the first to announce for the 2020 senate race in Arizona. It's the seat currently held by Martha McSally who was appointed at the end of 2018 to fill the late Sen. John McCain's seat days after Jon Kyl turned in his resignation letter. Kyl had been appointed to fill the seat after McCain's death.

McSally lost her race against Sen. Kyrsten Sinema and will have to run again in 2020 if she wants to keep the seat she currently holds.

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The winner of the 2020 race will then have to run again in 2022 when John McCain's unfinished six-year term officially ends.

If Kelly wins, he'll be the third astronaut elected to the U.S. Senate.