Working in Space

Astronauts have a tremendous amount of work to do while living in space. Tasks range from operating state-of-the-art robotics equipment to conducting space science experiments on behalf of scientists on the ground. Astronauts are also responsible for repairs, maintaining onboard systems, cleaning and food preparation. Over the course of a mission, astronauts may be required to do the work of a scientist, a construction worker, a communications officer, a housekeeper, a doctor and a pilot. Often, there are more tasks to be done then there are hours to do them. For this reason, Mission Control establishes detailed schedules for each crewmember, both to allow them to complete as much work as possible, as well as to make time available for rest and exercise. For an example, see a day-by-day report of the work done by Chris Hadfield and the rest of the crew during Mission STS-100.


In space, astronauts conduct experiments to gain a better understanding of the effects of weightlessness on various materials and life forms. In addition to conducting experiments, astronauts also act as subjects for some of those experiments.

For example, during Mission STS-78 in 1996, Canadian astronaut Bob Thirsk participated in an onboard life sciences experiment designed by Dr. Douglas Watt of McGill University in Montreal. The Torso Rotation Experiment examined eye, head and body movements in relation to the symptoms of motion sickness that many astronauts experience in space. Thirsk, a medical doctor, was both subject and researcher for these investigations. During the mission, he and three other astronauts wore a head and chin device, like a miner's lamp, to monitor movements of the eye, head and upper torso to determine if the normal pattern of coordination is changed as a result of microgravity. By studying what inadvertent movements astronauts may make as a result of living in weightlessness, new techniques can be developed to assist astronauts on future missions.

In 2009, when Thirsk was a flight engineer on board the International Space Station during Expedition 20/21, he conducted several Canadian experiments. One of these was the Bodies in the Space Environment (BISE) study. Thirsk, as test-subject, viewed several images through an occluded viewer. Each time he perceived that a revolving letter “p” became a “d”, (and vice-versa) Thirsk would click a button on his laptop. This determined his perception of the direction up. Scientists observed whether subjects relied more on visual cues or body cues (the feeling of being upright) in the weightless environment. A number of other expedition astronauts took part in this study, including NASA astronaut Nicole Stott. It is expected that results from BISE will assist people with balance and movement-control disorders.


A spacewalk, or Extra-Vehicular Activity (EVA), is one of the most difficult tasks that astronauts perform while working in space. EVAs are conducted when equipment repairs need to be made (such as the Hubble telescope), or intricate construction work that can only be done by human hands is required. EVAs typically last between five and seven hours. During an EVA, astronauts wear space suits, which provide them with life support functions, including protection from the extreme temperature fluctuations experienced in space.

On April 22, 2001, CSA Astronaut Chris Hadfield made history by becoming the first Canadian to perform an EVA. Hadfield and US astronaut Scott Parazynski worked for hours to unwrap and install Canadarm2, using existing robotic equipment and other tools. Since Chris' milestone excursion, two Canadians have followed “suit”: Steve MacLean in 2006 during STS-115, and Dave Williams in 2007 on STS-118. Williams has the distinction of logging the most time in space: 17 hours and 43 minutes over three spacewalks.

Onboard Training

Astronauts spend years training for their missions in space, and often will spend hundreds of hours just training for a very specific task, such as operating Canadarm2. For long-duration spaceflights, astronauts continue training during a mission in order to maintain their skills. Crewmembers participate in mandatory training sessions onboard the ISS, using software and simulators to maintain applicable skills and to train for new tasks. In addition to maintaining their technical skills, fitness training is also an essential part of this onboard program, both to maintain physical strength, and to minimize muscle and bone deterioration, which occurs as a result of living in microgravity.


Throughout a mission, astronauts communicate with many different groups including Mission Control, scientists involved with onboard experiments, students and the media. Crewmembers constantly receive information from the ground, and each day the crew holds a brief meeting after breakfast to distribute and review any new communications and make changes to their schedules if necessary. Astronauts also participate in regular videoconferences: Private Medical Conferences with the Flight Surgeon, regular Private Psychological Conferences with the psychologist and Private Family Conferences with family and friends.

On-Orbit Maintenance

Unlike a shuttle, the ISS never returns to the ground. This means that crewmembers aboard the ISS are responsible not only for operating the Station, but for maintaining it as well. Considering that the ISS could be in orbit for another ten years, maintenance is crucial to ensuring its longevity. The two types of on-orbit maintenance are preventative and corrective. Preventative maintenance involves inspection, replacement and cleaning tasks that the astronauts train for prior to their mission. Corrective maintenance requires the astronauts to fix a broken or non-functional piece of equipment. This type of action involves troubleshooting and testing in order to deal with an unforeseen situation. For instance, CSA Astronaut Bob Thirsk was tasked with fixing a key component of the Oxygen Generator System—a technology integral to life-support on the Station.

In addition to more complex maintenance tasks, astronauts are also required to keep the ISS and the shuttle clean. Because floating debris like crumbs and hair could get lodged into control panels and cause damage, crewmembers use a vacuum cleaner to remove stray particles from the air. Astronauts use wet wipes to clean any spills from equipment or experiments so that potentially harmful bacteria can not develop. Other minor maintenance tasks include cleaning the bathroom and kitchen areas.

NASA astronaut Nicole Stott, crewmate of CSA Astronaut Bob Thirsk during Expedition 20/21, participates in a BISE (Bodies in the Space Environment) session in the U.S. Laboratory Destiny. November 13, 2009. (Credit: NASA)

CSA Astronaut Chris Hadfield, STS-100 Mission Specialist, peers into the crew cabin of Space Shuttle Endeavour during a lengthy spacewalk to install Canadarm2 on the International Space Station (ISS). April 22, 2001. (Credit: NASA)

Cosmonaut Oleg V. Kotov, Expedition 15 flight engineer representing Russia's Federal Space Agency, and NASA astronaut Sunita L. Williams, flight engineer, participate in a Space Station Remote Manipulator System (SSRMS) training session using the Robotic Onboard Trainer (ROBOT) simulator in the Unity node of the International Space Station. April 17, 2007. (Credit: NASA)

CSA Astronaut Robert Thirsk speaks to his childhood hero, Montreal Canadiens hockey legend Jean Béliveau, from the International Space Station. This downlink event was held at the Canadian Space Agency Headquarters in Longueuil, Quebec, to highlight more than 100 days in space for Thirsk. September 14, 2009. (Credit: Canadian Space Agency)

Performing corrective maintenance, Canadian Space Agency Astronaut Bob Thirsk displays the Water Orbit Replaceable Unit, which he removed and replaced to restore the Oxygen Generator System to full-working capacity on board the International Space Station. August 27, 2009. (Credit: NASA)

How do you control the International Space Station, a ship the size of five hockey rinks? And from where? CSA Astronaut Chris Hadfield answers these questions from inside the ISS. (Credit: CSA/NASA)

Highlights of the milestone Transfer of Command ceremony that made Chris Hadfield the first Canadian Commander of the International Space Station. Hadfield will lead Expedition 35 until he returns with his crew mates in mid-May, 2013. (Credit: CSA/NASA)

CSA Astronaut Chris Hadfield performed a simple science experiment designed by grade 10 High School students. (Credit: CSA/NASA)

CSA Astronaut Chris Hadfield stores biological samples in the MELFI freezer of the Space Station. (Credit: CSA/NASA)

If a fire occurs on the International Space Station, astronauts wear quick-don masks to fight the emergency or evacuate. ISS Commander Chris Hadfield has fun at work, expelling oxygen from an expired quick-don mask tank. Spoiler alert: he sings! (Credit: CSA/NASA)

CSA Astronaut Chris Hadfield stows spacesuits in the Station's airlock where they will be checked for any possible wear and tear. (Credit: CSA/NASA)