Hi, I’m Tim Peake and welcome on board the International Space Station! While we are on Earth, we don’t realize how important the pull of gravity is to our overall health. Up here in space, because we are floating, we have to exercise daily to limit the impact on our cardiovascular system. In space, the changes to our heart and our blood vessels are quite striking: did you know that during a six-month space mission, an astronaut’s cardiovascular system can age by up to 10 or 20 years? This surprising discovery was made by Professor Richard Hughson, a Canadian scientist at the University of Waterloo. With the help of the Canadian Space Agency, Professor Hughson is currently working on an experiment called Vascular Echo. This is his fourth study on board the International Space Station. Vascular Echo examines changes in heart and blood vessels while astronauts are in space, and monitors their recovery when they return to Earth. A chronic increase in blood pressure in our head and our neck while in space can result in stiffer arteries. Changes in our cardiovascular system might also reflect other risk factors, including the overall reduction in levels of physical activity as we float in space. This can result in insulin resistance, which is a cause of Type 2 diabetes on Earth. Nine astronauts will take part in Vascular Echo by providing blood samples and taking ultrasounds of their arteries before, during and after their missions to space. The knowledge we gain from Vascular Echo could help keep astronauts healthy in space. It could also benefit people on Earth, especially those who are sedentary, the elderly, or bedridden patients.