A new era opened on Sunday July 11 when Virgin Galactic founder Richard Branson flew alongside Virgin Galactic employees Beth Moses, Sirisha Bandla, and Colin Bennett above 80 km, NASA’s definition of space. In doing so, these pilots and crew opened a future that is both full of promise and uncertainty. The world could soon start witnessing increasing number of tourists to the space. Question: How long can someone survive in space?
Funny how the article explains it:
Whatever you do, don’t hold your breath! The vacuum of space will pull the air from your body. So if there’s air left in your lungs, they will rupture.
Oxygen in the rest of your body will also expand. You’ll balloon up to twice your normal size, but you won’t explode. Your skin is elastic enough to hold you together.
Any exposed liquid on your body will begin to vaporize. So the surfaces of your tongue and eyes will boil. Without air in your lungs, blood will stop sending oxygen to your brain.
You’ll pass out after about 15 seconds. 90 seconds after exposure, you’ll die from asphyxiation. It’s also very cold in space. You’ll eventually freeze solid.
According to labmate:
To date, the longest continuous amount of time a human has spent in space is 437 days. This feat was lived out by Russian astronaut Valeri Polyakov. When it comes to total number of days spent in space, fellow Russian Sergei Krikalev takes the cake, with over 803 days in space, spread out over six flights.
The physical effects of space
So what makes it so difficult to survive in space? For starters, the human body has evolved to function under gravitational conditions. This means that space is a harsh condition for humans. As muscles constantly work against gravity on planet Earth, they start to deteriorate in space. This includes the heart, which shrinks.
As bones are no longer needed to support the body’s weight they neglect the need to maintain themselves. While bone tissue is still absorbed it’s not rebuilt, which can cause fractures and kidney stones. Research has also shown that extended periods in space can dysregulate the immune system, and leave astronauts vulnerable to pathogens, hypersensitivity and unwanted autoimmune responses.
The risk of radiation
Radiation is another serious threat, with astronauts continuously exposed to multiple forms of energy, including solar radiation, galactic cosmic radiation, geomagnetically bound radiation and solar cosmic particles. Overexposure can trigger serious cell mutation, leading to cancer, epigenetic effects and even death. Radiation can also impair bodily functions, causing bone marrow to deteriorate, the immune system to weaken and cataracts to develop in the eyes. Even with next generation shielding materials to protect them, astronauts are still at risk of secondary radiation from gamma rays and energetic neutrons.
While radiation can be a serious health problem, light also plays a major role in modern science. ‘Light Source Characterisation in Life Sciences’ explores photonics in further detail, and its role in a myriad of life science arenas, including biological research, biomedical instrumentation and agriculture. From effective UV disinfection and optimal aquarium illumination to accurate blood oximetry, success depends largely on the ability to understand the performance of certain light sources.