NASA Extreme Environment Mission Operations, or NEEMO, is a
NASA
The National Aeronautics and Space Administration (NASA ) is an independent agencies of the United States government, independent agency of the federal government of the United States, US federal government responsible for the United States ...
analog mission that sends groups of astronauts, engineers and scientists to live in the
Aquarius underwater laboratory, the world's only undersea research station, for up to three weeks at a time in preparation for future
space exploration
Space exploration is the process of utilizing astronomy and space technology to investigate outer space. While the exploration of space is currently carried out mainly by astronomers with telescopes, its physical exploration is conducted bo ...
.
Aquarius is an
underwater habitat
Underwater habitats are underwater structures in which people can live for extended periods and carry out most of the Circadian rhythm, basic human functions of a 24-hour day, such as working, resting, eating, attending to personal hygiene, and ...
off
Key Largo, Florida
Key Largo is an unincorporated area and census-designated place in Monroe County, Florida, United States, located on the island of Key Largo in the upper Florida Keys. The population was 12,447 at the 2020 census, up from 10,433 in 2010. The ...
, in the Florida Keys National Marine Sanctuary. It is deployed on the ocean floor next to deep coral reefs below the surface.
NASA has used it since 2001 for a series of space exploration simulation missions, usually lasting 7 to 14 days, with space research mainly conducted by international
astronaut
An astronaut (from the Ancient Greek (), meaning 'star', and (), meaning 'sailor') is a person trained, equipped, and deployed by a List of human spaceflight programs, human spaceflight program to serve as a commander or crew member of a spa ...
s. The mission had cost about 500 million U.S. dollars. The crew members are called
aquanaut
An aquanaut is any person who remains underwater, breathing at the ambient pressure for long enough for the concentration of the inert components of the breathing gas dissolved in the body tissues to reach equilibrium, in a state known as sat ...
s (as they live underwater at depth pressure for a period equal to or greater than 24 continuous hours without returning to the surface), and they perform
EVAs in the underwater environment.
A technique known as
saturation diving
Saturation diving is an ambient pressure diving technique which allows a diver to remain at working depth for extended periods during which the body tissues become solubility, saturated with metabolically inert gas from the breathing gas mixture ...
allows the aquanauts to live and work underwater for days or weeks at a time. After twenty four hours underwater at any depth, the human body becomes saturated with dissolved gas. With saturation diving, divers can accurately predict exactly how much time they need to decompress before returning to the surface. This information limits the risk of
decompression sickness
Decompression sickness (DCS; also called divers' disease, the bends, aerobullosis, and caisson disease) is a medical condition caused by dissolved gases emerging from Solution (chemistry), solution as bubbles inside the body tissues during D ...
. By living in the Aquarius habitat and working at the same depth on the ocean floor, NEEMO crews are able to remain underwater for the duration of their mission.
For NASA, the Aquarius habitat and its surroundings provide a convincing analog for space exploration.
Much like space, the undersea world is a hostile, alien place for humans to live. NEEMO crew members experience some of the same challenges there that they would on a distant asteroid, planet (i.e. Mars) or Moon. During NEEMO missions, the aquanauts are able to simulate living on a spacecraft and test spacewalk techniques for future space missions. Working in space and underwater environments requires extensive planning and sophisticated equipment. The underwater condition has the additional benefit of allowing NASA to "weight" the aquanauts to simulate different gravity environments.
Until 2012, Aquarius was owned by the
National Oceanic and Atmospheric Administration
The National Oceanic and Atmospheric Administration (NOAA ) is an American scientific and regulatory agency charged with Weather forecasting, forecasting weather, monitoring oceanic and atmospheric conditions, Hydrography, charting the seas, ...
(NOAA) and operated by the
National Undersea Research Center (NURC) at the
University of North Carolina–Wilmington as a
marine biology
Marine biology is the scientific study of the biology of marine life, organisms that inhabit the sea. Given that in biology many scientific classification, phyla, family (biology), families and genera have some species that live in the sea and ...
study base.
Since 2013, Aquarius is owned by
Florida International University
Florida International University (FIU) is a public research university with its main campus in Westchester, Florida, United States. Founded in 1965 by the Florida Legislature, the school opened to students in 1972. FIU is the third-largest univ ...
(FIU). As part of the FIU Marine Education and Research Initiative, the Medina Aquarius Program is dedicated to the study and preservation of marine ecosystems worldwide and is enhancing the scope and impact of FIU on research, educational outreach, technology development, and professional training. At the heart of the program is the Aquarius Reef Base.
Missions
NEEMO 1: October 21–27, 2001

NASA Aquanaut Crew:
*
Bill Todd , Commander
*
Michael L. Gernhardt
*
Michael López-Alegría
Michael López-Alegría (born Miguel Eladio López Alegría on May 30, 1958) is an astronaut, test pilot and commercial astronaut with dual nationality, American and Spanish; a veteran of three Space Shuttle missions and one International Space ...
*
Dafydd Williams
Dafydd "David" Rhys Williams (born May 16, 1954) is a Canadian physician, public speaker, author and retired CSA astronaut. Williams was a mission specialist on two Space Shuttle missions. His first spaceflight, STS-90 in 1998, was a 16-day mi ...
,
CSA
NURC Support Crew:
*
Mark Hulsbeck
*
Ryan Snow
NEEMO 2: May 13–20, 2002
NASA Aquanaut Crew:
*
Michael Fincke
Edward Michael "Mike" Fincke (born March 14, 1967) is an American astronaut and retired United States Air Force colonel. He formerly held the American record for the most time in space (382 days) until it was broken by Scott Kelly on October 16 ...
, Commander
*
Daniel M. Tani
*
Sunita Williams
*
Marc Reagan
NURC Support Crew:
* Thor Dunmire
*
Ryan Snow
NEEMO 3: July 15–21, 2002
NASA Aquanaut Crew:
*
Jeffrey Williams , Commander
*
Gregory Chamitoff
*
John D. Olivas
*
Jonathan Dory
Jonathan Robert Dory is a Human Systems Integration Lead at NASA's Johnson Space Center (JSC) in Houston, Texas. He is Branch Chief of NASA's Habitability and Human Factors Branch, part of the Habitability and Environmental Factors Division at ...
NURC Support Crew:
* Byron Croker
* Michael Smith
NEEMO 4: September 23–27, 2002
NASA Aquanaut Crew:
*
Scott Kelly , Commander
*
Paul Hill
*
Rex Walheim
*
Jessica Meir
NURC Support Crew:
*
James Talacek
*
Ryan Snow
NEEMO 5: June 16–29, 2003
NASA Aquanaut Crew:
*
Peggy Whitson , Commander
*
Clayton Anderson
*
Garrett Reisman
Garrett Erin Reisman (; born February 10, 1968) is an American engineer and former NASA astronaut. He was a backup crew member for Expedition 15 and joined Expedition 16 aboard the International Space Station for a short time before becoming a mem ...
*
Emma Hwang
NURC Support Crew:
*
James Talacek
*
Ryan Snow
NEEMO 6: July 12–21, 2004
NASA Aquanaut Crew:
*
John Herrington , Commander
*
Nicholas Patrick
*
Douglas H. Wheelock
*
Tara Ruttley
NURC Support Crew:
*
Craig B. Cooper
* Joseph March,
*
Marc Reagan, Mission Director
NEEMO 7: October 11–21, 2004
NASA Aquanaut Crew:
*
Robert Thirsk
Robert "Bob" Brent Thirsk, (born August 17, 1953) is a Canadian retired engineer and physician, and a former Canadian Space Agency astronaut. He holds the Canadian record for the most time spent in space (204 days, 18 hours and 29&nbs ...
, Commander
*
Catherine Coleman
*
Michael R. Barratt
*
Craig McKinley
NURC Support Crew:
*
James Talacek
*
Billy Cooksey
*
Bill Todd, Mission Director
NEEMO 8: April 20–22, 2005
NASA Aquanaut Crew:
*
Michael L. Gernhardt , Commander
*
John D. Olivas
*
Scott Kelly
* Monika Schultz
NURC Support Crew:
*
Craig B. Cooper
* Joseph March
*
Bill Todd, Mission Director
NEEMO 9: April 3–20, 2006

NASA Aquanaut Crew:
*
Dafydd Williams
Dafydd "David" Rhys Williams (born May 16, 1954) is a Canadian physician, public speaker, author and retired CSA astronaut. Williams was a mission specialist on two Space Shuttle missions. His first spaceflight, STS-90 in 1998, was a 16-day mi ...
, Commander
*
Nicole P. Stott
*
Ronald J. Garan Jr.
*
Timothy J. Broderick , M.D.
NURC Support Crew:
*
James F. Buckley
* Ross Hein
*
Marc Reagan, Mission Director
NEEMO 10: July 22–28, 2006
NASA Aquanaut Crew:
*
Koichi Wakata
is a Japanese engineer and an astronaut working for Axiom Space. Wakata retired from JAXA in 2024 after a career in spaceflight spanning nearly two decades. He logged over 500 days in space across five missions: three aboard the Space Shuttle, ...
, Commander
*
Andrew Feustel
*
Karen L. Nyberg
*
Karen Kohanowich
NURC Support Crew:
*
Mark Hulsbeck
*
Dominic Landucci
*
Marc Reagan, Mission Director
NEEMO 11: September 16–22, 2006
NASA Aquanaut Crew:
*
Sandra Magnus
Sandra Hall Magnus (born October 30, 1964) is an American engineer and a former NASA astronaut. She flew to space three times, as mission specialist on STS-112, as ISS crewmember during Expedition 18 and as mission specialist on STS-135. She is al ...
, Commander
*
Timothy Kopra
*
Robert L. Behnken
*
Timothy Creamer
NURC Support Crew:
* Larry Ward
* Roger Garcia
*
Marc Reagan, Mission Director
NEEMO 12: May 7–18, 2007

NASA Aquanaut Crew:
*
Heidemarie Stefanyshyn-Piper, Commander
*
José M. Hernández
*
Josef Schmid, M.D.
*
Timothy J. Broderick, M.D.
NURC Support Crew:
*
Dominic Landucci
*
James Talacek
*
Marc Reagan, Mission Director
NEEMO 13: August 6–15, 2007
NASA Aquanaut Crew:
*
Nicholas Patrick, Commander
*
Richard R. Arnold
*
Satoshi Furukawa
*
Christopher E. Gerty
NURC Support Crew:
*
James F. Buckley
*
Dewey Smith
*
Marc Reagan, Mission Director
NEEMO 14: May 10–23, 2010
NASA Aquanaut Crew:
*
Chris Hadfield
Chris Austin Hadfield (born August 29, 1959) is a Canadian retired astronaut, engineer, fighter pilot, musician, and writer. As the first Canadian to perform extravehicular activity in outer space, he has flown two Space Shuttle missions and ...
, Commander
*
Thomas H. Marshburn
*
Andrew Abercromby
*
Steve Chappell
Steven Patrick Chappell (born 1969/1970) is an American aerospace engineer. He is a Technical Lead & Research Specialist for Wyle Laboratories, Wyle Integrated Science & Engineering at NASA's Johnson Space Center (JSC) in Houston, Texas. He is ...
Aquarius Reef Base support crew:
*
James Talacek
* Nate Bender
*
Bill Todd, Mission Director
NEEMO 15: October 20–26, 2011
NASA Aquanaut Crew:
*
Shannon Walker, Commander
*
Takuya Onishi
*
David Saint-Jacques
*
Steve Squyres
Steven Weldon Squyres (born January 9, 1956) is an American geologist and planetary scientist. He was the James A. Weeks Professor of Physical Sciences at Cornell University in Ithaca, New York. His research area is in planetary sciences, with a ...
Aquarius Reef Base support crew:
*
James Talacek
* Nate Bender
DeepWorker 2000 submersible
A submersible is an underwater vehicle which needs to be transported and supported by a larger ship, watercraft or dock, platform. This distinguishes submersibles from submarines, which are self-supporting and capable of prolonged independent ope ...
crew:
*
Stanley G. Love
*
Richard R. Arnold
*
Michael L. Gernhardt
NEEMO 16: June 11–22, 2012

NASA Aquanaut Crew:
*
Dorothy Metcalf-Lindenburger, Commander
*
Kimiya Yui
*
Timothy Peake
*
Steve Squyres
Steven Weldon Squyres (born January 9, 1956) is an American geologist and planetary scientist. He was the James A. Weeks Professor of Physical Sciences at Cornell University in Ithaca, New York. His research area is in planetary sciences, with a ...
Aquarius Reef Base support crew:
*
James Talacek
*
Justin Brown
DeepWorker 2000 submersible
A submersible is an underwater vehicle which needs to be transported and supported by a larger ship, watercraft or dock, platform. This distinguishes submersibles from submarines, which are self-supporting and capable of prolonged independent ope ...
crew:
*
Stanley G. Love
*
Steve Giddings
*
Serena M. Auñón
*
Bill Todd
*
Michael L. Gernhardt
*
Andrew Abercromby
*
Steve Chappell
Steven Patrick Chappell (born 1969/1970) is an American aerospace engineer. He is a Technical Lead & Research Specialist for Wyle Laboratories, Wyle Integrated Science & Engineering at NASA's Johnson Space Center (JSC) in Houston, Texas. He is ...
SEATEST II: September 9–13, 2013
Space Environment Analog for Testing EVA Systems and Training
( NEEMO 17 ) Designation skipped
NASA Aquanaut Crew:
*
Joseph M. Acaba
Joseph Michael Acabá (born May 17, 1967) is an American educator, hydrogeologist, and NASA astronaut. In May 2004, he became the first person of Puerto Rican ancestry to be named as a NASA astronaut candidate, when he was selected as a member ...
, Commander
*
Kate Rubins
*
Andreas Mogensen
*
Soichi Noguchi
is a Japanese aeronautical engineer and former Japan Aerospace Exploration Agency, JAXA astronaut. His first spaceflight was as a mission specialist aboard STS-114 on 26 July 2005 for NASA's first "return to flight" Space Shuttle program, Spac ...
Aquarius Reef Base support crew:
*
Mark Hulsbeck
*
Otto Rutten
NEEMO 18: July 21–29, 2014
NASA Aquanaut Crew:
*
Akihiko Hoshide
is a Japanese engineer, JAXA
The is the Japanese national air and space agency. Through the merger of three previously independent organizations, JAXA was formed on 1 October 2003. JAXA is responsible for research, technology developm ...
, Commander
*
Jeanette J. Epps
*
Mark T. Vande Hei
Mark Thomas Vande Hei (born November 10, 1966) is a retired United States Army officer and current NASA astronaut who has served as a flight engineer for Expedition 53, 54, 64, 65, and 66 on the International Space Station.
Early life and e ...
*
Thomas Pesquet
Thomas Gautier Pesquet (; born 27 February 1978) is a French aerospace engineer, aviator, pilot, European Space Agency astronaut, actor, musician, and writer. Pesquet was selected by ESA as a candidate in May 2009, and he successfully completed ...
Professional habitat technicians, Aquarius Reef Base support crew:
*
James Talacek
* Hank Stark (FIU)
NEEMO 19: September 7–13, 2014

NASA Aquanaut Crew:
*
Randolph Bresnik
Randolph James "Komrade" Bresnik (born September 11, 1967) is a retired officer in the United States Marine Corps and an active NASA astronaut. A United States Marine Corps Aviation, Marine Aviator by trade, Bresnik was selected as a member of NA ...
, Commander
*
Andreas Mogensen, Flight Engineer 1
*
Jeremy Hansen, Flight Engineer 2
*
Hervé Stevenin, Flight Engineer 3
Aquarius Reef Base support crew:
*
Mark Hulsbeck
*
Ryan LaPete
NEEMO 20: July 20 – August 2, 2015
NASA Aquanaut Crew:

*
Luca Parmitano
Luca Parmitano (born 27 September 1976 in Paternò, Sicily) is an Italian astronaut in the European Astronaut Corps for the European Space Agency (ESA). He was selected as an ESA astronaut in May 2009. Parmitano is also a colonel and test pilot ...
,
ESA, commander
*
Serena M. Auñón, NASA
* David Coan, NASA EVA Management Office engineer
*
Norishige Kanai,
JAXA
The is the Japanese national air and space agency. Through the merger of three previously independent organizations, JAXA was formed on 1 October 2003. JAXA is responsible for research, technology development and launch of satellites into o ...
Professional habitat technicians, Aquarius Reef Base support crew:
*
Mark Hulsbeck (FIU)
* Sean Moore (FIU)
NEEMO 20 mission objective was to simulate the time delays associated with sending and receiving commands between controllers on Earth and astronauts on Mars. Additional EVAs will simulate working on the surface of an asteroid, and the use of the DeepWorker submersible as an underwater stand-in for the
Multi-Mission Space Exploration Vehicle.
NEEMO 21: July 21 – August 5, 2016

The NEEMO 21 mission was scheduled to begin July 18, 2016 and conclude August 3, 2016; however, the mission start was shifted to July 21, 2016 as a result of unfavorable weather conditions.
NASA Aquanaut Crew:
*
Reid Wiseman, NASA, Commander 1
*
Megan McArthur, NASA, Commander 2
* Marc O´Gríofa
*
Matthias Maurer, ESA
* Noel Du Toit
* Dawn Kernagis
Professional habitat technicians, Aquarius Reef Base support crew:
* Hank Stark (FIU)
* Sean Moore (FIU)
NEEMO 22: June 18–27, 2017
NASA Aquanaut Crew:
*
Kjell Lindgren, NASA, Commander
*
Pedro Duque
Pedro Francisco Duque Duque, Order of Friendship, OF, Medal "For Merit in Space Exploration", OMSE (born Madrid, 14 March 1963) is a Spanish astronaut and aeronautics engineer who served as Ministry of Science (Spain), minister of Science from ...
, ESA
* Trevor Graff, NASA/Jacobs
* Dominic D'Agostino, USF
Professional habitat technicians, Aquarius Reef Base support crew:
*
Mark Hulsbeck (FIU)
* Sean Moore (FIU)
NEEMO 23: June 10–22, 2019
NASA all-female Aquanaut Crew:
*
Samantha Cristoforetti
Samantha Cristoforetti (; born 26 April 1977) is an Italian European Astronaut Corps, European Space Agency (ESA) astronaut, former Italian Air Force pilot and engineer. She is the second of two Women in space, women sent into space by ESA and ...
, ESA, Commander
*
Jessica Watkins, NASA astronaut candidate
* Csilla Ari D’Agostino, a neurobiologist at the University of South Florida
* Shirley Pomponi, Marine biologist at Harbor Branch Oceanographic Institute of Florida Atlantic University
Professional habitat technicians, Aquarius Reef Base support crew:
*
Mark Hulsbeck (FIU)
* Tom Horn (FIU)
See also
*
*
References
External links
*
NEEMO missionsLive webcams (subject to mission availability)
{{DEFAULTSORT:Neemo
NASA programs
Controlled ecological life support systems
Human analog missions