Our recent robotic expeditions in Mars have given us plenty of information about the red planet, like the fact that our closest neighbor possibly had enough water to sustain ancient life, or that the methane amount in the Martian atmosphere hints to the possibility of microbial life on Mars.
The latest discoveries surround at the possibility that maybe, just maybe, we have actual alien neighbors living in Mars, and we uncover more and more clues to this as NASA's expeditions become engaged with more complex discoveries
Whether or not NASA actually discovers life on Mars isn't an issue for these students from the University of Southampton. For them, it's a question of how you actually introduce life to the red planet. This team of engineering and biology students, lead by aspiring space engineer Suzanna Lucarotti, has devised a plan to grow lettuce on Mars. On a recent Reddit AMA, Lucarotti and the team explained to space exploration fans how they intend to grow the leafy vegetable on Mars' lifeless surface. Here are some of the most intriguing questions asked during their AMA.
Redditor Damany asked, "Why lettuce and not, say, soy or corn?"
"We have chosen lettuce for a number of reasons.Redditor kiriti asked, "Hasn't it already been proven that we are able go grow plants in space? What specific environment does growing lettuce on Mars achieve that couldn't be replicated on earth. Except the low gravity."
"First and most important: it is widely used as a test plant for closed systems. It is growing currently in Mars simulation experiments on Earth, and even on the ISS in orbit. So we have a lot of data on how lettuce will behave on Mars, but nearly no such data about corn.
"Secondly, lettuce is wholly edible, while we only eat the seeds of soy and corn, and we throw most of the plants away. So lettuce converts nutrients to edible material with low waste.
"Third, lettuce grows fast and is easy to fit into a micro greenhouse: its basically edible within 4 weeks of germination. For corn we would need to wait months, and design a huge greenhouse that could house that big plant"
"You are right, we can grow plants in space because we have already tried that. Lettuce is growing at this very moment on the ISS as part of the NASA VEGGIE project. But that is not on Mars.Redditor bold_algorithm asked, "Are you afraid that the Mars Lettuce will evolve into an aggressive, hostile, intelligent plant that will see humans as a rival species, and try to destroy us? How can you prevent such a circumstance?"
"No one has ever grown anything on Mars, only in Mars analog setups on Earth. These models are not perfect and each only simulate a part of the Martian environment.
"Gravity and radiation are the two really tricky ones. Creating cosmic radiation artificially is no small task, other teams usually use simpler radiations, which are not perfect substitutes.
"Gravity is equally challenging, we can use centrifuges but those have severe limits themselves.
"So we are not only going to see if plants can actually grow on Mars, and not only in imperfect simulations, but we will also answer a very important second question:
"Can plants from Earth grow using resources from Mars?
"We are going to answer that by filtering CO2 from Martian air and feeding it to our lettuce seedlings there. This is again something that we cannot reproduce on Earth."
The team said, "Yes, this was a great concern to us. The all-powerful 'Mars Lettuce' haunted our dreams whilst we were still trying to come up with a solution to this. Ultimately we prevent this by using HEPA filters in the airlock and incinerating the lettuce upon completion."
Read the rest of the AMA here.