Without Earth-like pressure in space, the oxygen in your bloodstream will begin to reverse-dissolve and escape from your blood. There is a lot of hard work astronauts need to do in space. When astronauts lose their oxygen in their blood, they become weaker and it is harder for them to do their tasks in space. According to NASA, “after space flight, the ability of a person's body to regulate blood pressure while upright is reduced.” That means that you become weaker since the calcium is dissolving out of the bones and into the blood. An object that can solve this problem is the Flash Sensor. The Flash Sensor is a light that can look through your skin on your fingers and see your blood flow and blood change. The only thing astronauts need to do is put one of their fingers on the flash. The Materials I used for this object aluminum for the flashlight, and glass for the light. When the astronauts are in Mars, they need to insert an LED light in the hole.