The race to return humans to the moon and eventually send astronauts to Mars has forced scientists to confront a difficult reality. Space is dangerous, isolated and unforgiving. When a medical emergency happens millions of miles from Earth, there is no nearby hospital waiting to help. One of the greatest concerns is sudden cardiac arrest. On Earth, doctors and first responders use cardiopulmonary resuscitation, or CPR, to keep blood flowing after the heart stops. In space, however, performing CPR becomes far more difficult because gravity itself changes how blood moves through the body. Now, researchers at Concordia University have developed a new high-fidelity simulator designed to study how CPR works in reduced gravity environments. Their findings, published in the journal npj Microgravity, could help future astronauts survive cardiac emergencies during long missions in deep space. The project combines engineering, medicine and space science into a system that mimics blood flow inside the human body. The simulator allowed scientists to track how artificial blood moved during CPR under both Earth gravity and hypogravity conditions. 3D-printing of …