The Hawaii Space Exploration Analog and Simulation (HI-SEAS) project is meant to simulate the conditions of space as much as is possible on Earth. For the duration of the mission, crew members reside at 8,200 feet in a dome on Mauna Loa. In some missions, including the Mars simulation, the crew is sealed in the dome. In others, they must wear suits whenever they step outside.

NASA funds the project, using it to study human behavior, train individuals for the conditions of space, and to help them learn what is needed to sustain humans throughout long-term space missions. It is run by the University of Hawaii.

HI-SEAS launched its sixth mission late last week, with four crew members. The crew was made up of two men and two women from four different countries of origin: Australia, Slovakia, Korea, and Scotland. This mission was intended to last eight months, simulating Mars exploration. It was suspended just five days after it began due to a medical incident injuring one of the crew members. The injured individual was taken to the Hilo Medical Center early in the morning with an undisclosed condition. They were released after a few hours of medical observation.

Safety protocols forced the rest of the crew to leave the HI-SEAS dome, suspending the rest of the mission. Authorities told reporters that an investigation into the dome must be completed before the mission can resume but were unable to provide a timeline or any details about the injury.

Additional details about the nature of the injury or the condition of the crew member were not released, to protect their privacy. It was noted that this is the first time a mission has been suspended due to injury. Project leaders are currently investigating and developing measures to prevent injuries in the future.