Market in my town is a very busy and important place. They are opened every weekend in the morning and evening. Framers from local bring their produce like fruits, vegetables, grains. They bring fresh produce to market in their carts.
It's a market where customers already have a lot of options. It's usually full of well-established businesses with years of experience serving the same customers. These markets are sometimes called saturated markets because they feel full
As for the first part, Cost, Radiation exposure to humans, No water or heat, and unfit soil. As for the second, Astronomers, Botanists, and obviously your fair share of rocket scientists and math matitions for the way up.
