The Mars500 mission came to an end on Nov. 4, 2011. The elaborate experiment, carried out by the European Space Agency (ESA) and Russia's Institute of Biomedical Problems, was the longest spaceflight simulation ever conducted, and reportedly cost $15 million.
A wealth of data was collected throughout the mission, and researchers are keen to better understand the physical and psychological challenges that astronauts will face on long-duration missions to Mars, or other deep-space destinations.
One recent expedition, NEEMO 15, was the first to simulate a trip to an asteroid, and aimed to test ways to explore the surface a space rock and perform science experiments on its surface.
The NEEMO 15 aquanauts splashed down on Oct. 20, 2011, for a 13-day mission, but the excursion was cut short six days later because of safety concerns surrounding Hurricane Rina, which at the time, was threatening to make landfall at Mexico's Yucatan peninsula nearby.
The agency's technology demonstration program, called Research and Technology Studies or Desert RATS, puts futuristic vehicles and devices to the test at Arizona's Black Point Lava Flow desert. The program, which has been held every year since 1998, helps scientists and engineers examine how their systems might perform on the surface of another world, which helps them plan future missions.
In August 2011, the Desert RATS field tests were primarily focused on asteroid exploration, and some of the technology that took center stage included a high-tech space truck for driving on the surface of other bodies, a robotic rover assistant, astronaut habitats and deep space communication systems.
The CAVES 2011 mission was designed to help the astronauts practice skills needed for real spaceflight, including operating in a potentially dangerous environment and working with an international crew.
Throughout the six-day mission, the astronauts also completed a variety of science objectives, including mapping, photography, monitoring air flow, temperature and humidity. Crewmembers also took geological and microbiological samples as part of their exploration objectives.
In 2008, as part of a NASA-sponsored program to kickstart innovation, a team of engineers from NASA, the National Science Foundation and ILC Dover, an engineering development and manufacturing company based in Federica, Del., developed concepts for inflatable lunar habitat modules. The initiative fell under the agency's now defunct Constellation program, which was aimed at returning astronauts to the moon.
The goal of the habitat project was to design, construct and test a prototype inflatable structure in an extremely harsh environment — Antarctica. The engineers focused on making the habitat lightweight, easy to deploy, and durable in the extreme conditions. In January 2008, the engineers tested prototype modules of the habitats while stationed at the McMurdo Complex in Antarctica.
More than 100 crews have visited the Utah site. The Mars Society also oversees another research station in the Canadian Arctic on Devon Island.
In 2011, the Pavilion Lake Research Project team embarked on a 10-day field test using small submarines, called DeepWorker submersible vehicles, to explore, study and document rare freshwater carbonate rock formations that thrive at Kelly Lake. NASA scientists will use these activities as a basis for exploration concepts for future manned missions to an asteroid and Mars.
The Haughton impact structure is located on Canada's Devon Island in the territory of Nunavut. It is about 103 miles from the Canadian hamlet of Resolute and about 800 miles away from the magnetic North Pole. Temperatures range from minus 22 degrees Fahrenheit (minus 30 Celsius) to 50 F (10 C).
Like Utah's Mars Desert Research Station, the Devon Island site is overseen by the Mars Society.
In addition to testing rover concepts, the scientist also studied ways that astronauts can use resources found at landing sites to generate oxygen. The In Situ Resource Utilization Project examined ways that astronauts could make their own oxygen from lunar rocks and soil.
These tests were part of NASA's now defunct Constellation program, which was aimed at sending astronauts back to the moon before it was canceled.