Simple fact of life that evolved on Earth, well technically most life that evolved on Earth, and by life I mean animal life, tangents are growing, back on track. A simple fact of animal life on Earth is that organisms like humans, whales, and nerds all need oxygen to survive. When we are not on planet Earth, we humans will often use advanced chemistry to filter out carbon dioxide and electrolysis to crack water into hydrogen and oxygen to replace the carbon dioxide that was scrubbed out. (Honestly the electrolysis thing is surprising to me, before I started writing this piece 10 minutes ago, I sincerely thought we had a chemical approach to at least partially directly recycle the waste gases made by the crew) This is a problem for long term exploration, if each breath of fresh O2 crew members need to breath in needs to be shipped up, via compressed air or chemically split water, your astronauts are going to be a tad too dependent on home base. NASA researchers and science fiction authors have put forth a myriad of solutions suggesting ways that plant life could be used to offset at least some of the crews oxygen production means. Some of my favorites include, specially bred plants with limited musculature that contracts and expands regularly causing air to move (I will try to add a link to the title of the sci-fi novel that has that idea later, found them, book 3 of the Night's Dawn Trilogy* ), in Vernor Vinge's A Deepness in the Sky the author describes a space fairing civilization that ensures that every ship no matter the size has some kind of small garden inside even if it is only a small terrarium, NASA is more pragmatically developing small hydroponic systems to grow lettuce. My suggestion takes inspiration from all of these ideas, creating a series of small semi-autonomous robotic growth media that are intended to float around the inside of space craft, providing air filtration, visual stimuli, and in emergencies a means to mitigate air from going stale.
This last detail I will give a little background, actually I won't, after 20 minutes of research it turns out I can't find a link to the story I thought I had read. The story that I do have is that of Astronaut Jerry Linenger and the Mir 23 crew. During the Mir 23 mission of series of disasters including fires inside of Mir and spacecraft collisions, astronauts and cosmonauts faced a litany of challenges including losing power. The detail that I thought I remembered, but cannot find a reference to, so this may be just unreliable memory, is that when the Mir crew lost power, they had to manually fan the air around them to avoid CO2 build up. (if I find the reference I shall add it in, if not well uhh, the false memory served as a source of inspiration)**
Anyways back to the idea, small robotic vehicles with semi-independent power supplies, designed to fly around the inside of a space craft. One potential version could have the vehicles embedded with special LEDs intended to serve two distinct but equally beneficial uses. The first is illumination for the plants/algae that grow on the robot, ensuring that the plants have sufficient energy to grow and provide enough clean air. The second feature is to aid in the sleep cycles of crew members, by increasing the relative ratios of red and blue light according to the time of day, astronauts might have an easier time falling asleep. Roughly speaking, if you increase the amount of blue light people experience in their environment, they are more prone to being awake, if you increase the amount of red light in the environment, people are more likely to feel sleepy. As plants only really use red and blue light to photosynthesis, it is not that unreasonable to carefully change the light output of the grow lights to accommodate the crew, and the plants, hopefully should not be any worse for the wear.
I hope you enjoy the concept, anyways I should go to bed, if so inspired I shall add conceptual renders down the line, or shitty drawings (the more likely scenario)
*Seriously, I highly recommend reading the Night's Dawn Trilogy, I read the books 10 years ago and many of the ideas have stuck with me.
(12/16/2015)**so i can't find the story about MIR, but someone posted an article on Reddit from the ESA on how astronauts need to sleep next to air ventilation systems to avoid suffocate in their own carbon dioxide.
(12/16/2015)**so i can't find the story about MIR, but someone posted an article on Reddit from the ESA on how astronauts need to sleep next to air ventilation systems to avoid suffocate in their own carbon dioxide.