Instead of heading out to space, NASA is going under the sea for one very special mission. In their latest expedition called NASA Extreme Environment Mission Operations 21 or NEEMO, NASA is headed to the bottom of the ocean. This is for their training for future missions to Mars.

A group of scientists, engineers, and astronauts are preparing for their deep sea adventure. The NEEMO team includes Matthias Maurer from European Space Agency, NASA astronaut Reid Wiseman, NASA astronaut Megan McArthur, Dawn Kernagis (Institute for Human & Machine Cognition), Marc O Griofa (Teloregen/VEGA/AirDocs), ad Noel Du Toit (Naval Postgraduate School).

For NEEMO, the team will be isolated at the bottom of the ocean, where the environment would prepare them for their 2030 Mars mission. The Aquarius Reef Base, which is 19 meters below sea level, is the location of the NEEMO mission. The mission is said to last 16 days, and had already started July 21.

"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," stated Bill Todd, the NEEMO Project Lead. "Equipment can fail, communication can be challenging and tasks can take longer than expected. 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."

A few tools and techniques will also be tested under the sea, one of which is a telemedicine device. Samples from the bottom of the ocean will also be collected for geology and marine biology studies.

"The aquanauts will also swim out of the Aquarius base to simulate spacewalks and pilot underwater vehicles. Their first challenge: building a coral nursery to practice their low-gravity construction skills," states a report.