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Frequently asked questions – International Space Station

International Space Station in general

What is the International Space Station?

The International Space Station (ISS) is a research laboratory that orbits Earth. Canada is one of the Station's partners, along with NASA (United States), the European Space Agency (which has 22 member states), JAXA (Japan), and Roscosmos (Russia).

Watch this video with David Saint-Jacques to learn more.

When was the first ISS module launched?

The first module of the ISS, Zarya, was launched on . Since then, many modules have been added to the Station in orbit. The Station's robotic arm, Canadarm2, was extensively involved in the assembly of the orbiting laboratory.

When did the first crew arrive at the ISS?

The first crew arrived at the Station on . Since then, the orbiting laboratory has been continuously inhabited by small groups of astronauts from around the world.

Where is the ISS located?

The Station orbits Earth at an altitude of about 400 km. You can observe the ISS's movements live on a map, try to spot the Station in the night sky, and even watch live videos from cameras on board the orbiting laboratory.

How fast is the ISS moving?

The ISS moves at 28,000 km/h. It takes 15 minutes for the Station to cross Canada and 90 minutes to travel around the globe. Every day, the ISS circles Earth 16 times, a distance roughly equal to a round trip to the Moon.

Is the Station visible from Earth?

Yes. The ISS is the second brightest object in the night sky after the Moon. It crosses the night sky like a bright star, and could easily be mistaken for an airplane, but it does not have blinking lights. Visit the See the Space Station page to learn how to spot the ISS when it flies over your region.

How big is the ISS?

The ISS is 109 metres by 73 metres, which is about five National Hockey League rinks wide and one rink long. It has 932 cubic metres of pressurized volume and weighs almost 410,000 kilograms. Its living space is about the size of a five-bedroom house.

What is the usual duration of a mission aboard the ISS?

Astronauts and cosmonauts usually spend about six months aboard the ISS for a mission. However, in , NASA astronaut Scott Kelly and Roscosmos cosmonaut Mikhail Kornienko lived on the ISS for a whole year to learn more about the long-term effects of living in space on the human body.

What is Canada's contribution to the ISS?

Building on its heritage of leading-edge space robotics, Canada contributed robots Canadarm2 and Dextre to the ISS, along with the Mobile Base System (MBS), a moveable work platform and a storage location. This sophisticated robotics suite was developed for the Canadian Space Agency (CSA) by MacDonald, Dettwiler and Associates Ltd. (MDA) of Brampton, Ontario. Visit the Canadian space robotics section to learn more.

This contribution has given Canada access to the orbiting laboratory to:

How many people work in the ISS program on Earth?

The ISS program involves more than 100,000 people in 16 countries. Over 500 Canadian organizations were involved in the supply chain that built Canadarm2, Dextre and the MBS, and sustained them on the ISS – from machine shops to software developers.

How many people usually live on the ISS?

The ISS has a permanent crew of three to six people.

How do people reach the ISS?

Until , people could fly to the ISS onboard a Soyuz spacecraft launching from Kazakhstan or a space shuttle launching from the United States. After the space shuttle program ended in , people could only fly to the ISS onboard a Soyuz spacecraft. In , a Crew Dragon spacecraft brought people to the ISS – the first commercial spacecraft to do so.

How many people have been on the ISS?

More than 240 individuals from 19 countries have visited the ISS.

Canadian Space Agency astronauts on the ISS

How many Canadian Space Agency (CSA) astronauts have been on the ISS?

Seven CSA astronauts have been on the ISS:

Who was the first Canadian to board the ISS?

Julie Payette was the first Canadian to board the Space Station during Mission STS-96, an assembly mission from to .

Who was the first Canadian commander of the ISS?

On , Chris Hadfield became the first Canadian to command a spaceship as Commander of the ISS during his third mission to space.

Who was the first Canadian to conduct a spacewalk?

Chris Hadfield was the first Canadian to leave a spacecraft and float freely in space. He conducted two spacewalks in to help attach the Canadarm2 to the ISS during Mission STS-100.

How many CSA astronauts have conducted a spacewalk?

Four CSA astronauts have conducted a spacewalk.

  • In , Chris Hadfield performed two spacewalks during Mission STS-100. He was the first Canadian to perform a spacewalk. In total, Chris spent 14 hours and 54 minutes outside.
  • In , Steve MacLean became the second Canadian to perform a spacewalk during Mission STS-115. He spent 7 hours and 11 minutes outside.
  • In , Dave Williams took part in three spacewalks during Mission STS-118. He spent 17 hours and 47 minutes outside, a record for a CSA astronaut.
  • In , David Saint-Jacques took part in his first spacewalk during Expedition 59. He worked outside the Station for 6 hours and 29 minutes.


What is Canadarm2?

Canadarm2 is a 17-metre-long robotic arm located on the ISS.

Canadarm2 became operational in . Since then, it has stayed permanently in space on board the ISS.

Canadarm2 was extensively involved in the assembly of the Space Station. It is now used to move pieces of equipment and supplies, install science experiments, and even carry Dextre and astronauts.

It has the unique ability to be commanded to move wherever it needs to go around the ISS. Each of its ends can be used as an anchor point while the other carries out various tasks.

In addition to general maintenance tasks, Canadarm2 is responsible for cosmic catches: it captures and docks unpiloted spacecraft (carrying everything from science instruments to necessities for the crew on board), and releases them at the end of their mission. Visit the Canadarm2 section to learn more.

What is Dextre?

Dextre is a versatile robot that maintains the ISS. It is the most sophisticated space robot ever built.

The space robot was launched on board Space Shuttle Endeavour and installed on the ISS in .

Dextre was designed to tackle the tough or routine jobs that need to be done in the harsh environment of space. The Station's robotic handyman allows astronauts to spend more time doing scientific experiments instead of going on risky spacewalks. Visit the Dextre section to learn more.

What is the Mobile Base System?

The Mobile Base System (MBS) is a moveable work platform and a storage location that glides on rails across the Space Station's main truss (or backbone). It can transport Canadarm2, Dextre, equipment or even astronauts on a spacewalk from one location to another. Visit the MBS page to learn more.

What are the benefits of Canadian space robotics on Earth?

Canadian robotics on the ISS have inspired technologies that improve our quality of life, like neuroArm, the world's first robot capable of performing surgery inside magnetic resonance machines; IGAR, an automated surgeon robot that performs operations based on instructions given by medical staff; and Modus V, a robotic digital microscope that positions itself with little effort from the surgeon. Visit the Benefits of Canadian space robotics on Earth section to learn more.

Science and technology

How many experiments have been conducted on the ISS?

A truly global endeavour, the unique microgravity laboratory has hosted almost 3,000 experiments from over 4,200 researchers in more than 100 countries.

Over 20 Canadian studies have been conducted aboard the ISS, some of which are still underway. These experiments are designed to:

  • study the effects of space travel on astronauts' bodies before astronauts undertake longer journeys further into our solar system
  • benefit Canadians and all of humanity
Why does Canada conduct science experiments in space?

Canada's participation in the ISS allows our scientists to access the unique space environment and conduct cutting-edge experiments aboard the orbiting laboratory to:

  • prepare for deep-space destinations
  • use the knowledge obtained to improve our quality of life on Earth

As international space agencies explore increasingly distant destinations, space travel must be made safer for astronauts. Canada's space science community makes an essential contribution to understanding issues related to the health and well-being of astronauts.

Canadian scientists use space to study our bones, heart, blood vessels and brain. This has led to discoveries that have helped:

  • develop new fitness strategies to improve the health of people at risk of cardiovascular diseases
  • increase our understanding of the early stages of Type 2 diabetes and other issues that may arise from increasingly sedentary lifestyles and aging

Visit the Why Canada conducts science on the ISS page to learn more.

How long have we been doing science on the ISS?

Canada has been doing science onboard the ISS since . H-Reflex was the first Canadian experiment.

How often do astronauts conduct science experiments on the ISS?

On average, there are 200 international space experiments on board the ISS at any given time. Canadian universities and companies in the space community are involved in advancing our knowledge of health and life sciences in space.

What have been the concrete benefits so far?

Visit the Benefits on Earth of previous Canadian scientific research on the ISS page to learn more.

Why is Canada focusing on health science experiments?

The effects of space on the human body are the biggest challenge we need to tackle in order to further explore the solar system.

Before we can send humans to Mars, for example, we need to mitigate a lot of risks to human health, such as the stiffening of arteries and the consequences of greater exposure to radiation.

Even though the research occurs in space, its findings have impacts here on Earth. The physical symptoms observed among astronauts on a mission are similar to accelerated aging and health problems experienced by sedentary populations. Therefore, the results of life science in space are also relevant for these fields of research.

Watch the Why do we do science in space? video to learn more.

Is Canada testing any technology on the ISS?

There are currently two Canadian technologies being tested on the Space Station:

  • The Bio-Monitor, a smart shirt system that monitors astronauts' vital signs
  • The Bio-Analyzer, a new tool to easily test different body fluids

In the past, Microflow, a portable Canadian technology that analyzed cells and hormones in blood or other biological samples, was also tested. Astronauts will soon test MicroPREP, a Canadian automated technology that aims to facilitate and accelerate the process of analyzing blood samples on Earth and in space. This new approach has the potential to empower personalized precision medicine in both clinical and remote settings by significantly reducing the sample preparation time and size, and human intervention required during medical testing. Visit the testing technologies section to learn more.

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