Who knew astronauts could prepare for life in space by living underwater?
Well, The NASA Extreme Environment Mission Operations (NEEMO)'s 21st mission began last week and lasts for a total of 16 days, according to The Washington Post.
Astronauts, scientists and engineers travel to the Florida Keys and spend their time approximately 60-feet underwater conducting experiments and going on "spacewalk" type dives.
During their time underwater, the international crew explores tools and techniques which are being tested for future space exploration, according to a statement from NASA.
"NEEMO 21 astronauts and crew will pioneer complex tasks on the seafloor utilizing the most advanced underwater navigation and science tools which are methodically choreographed to mimic a Mars exploration traverse," NEEMO Project Lead Bill Todd said.
For each of the six crew members, there are at least a dozen support team members working to make the mission successful, according to a blog about the mission.
"Equipment can fail, communication can be challenging and tasks can take longer than expected," Todd said. "Other tasks go just as planned. All cases are equally beneficial. It's how we learn and how we are able to assemble all of this together so that someday we're prepared for the unexpected when we are living on and traversing the Martian surface."
For more information about the mission follow #NEEMO21 on Twitter.