Understanding the behavior of bacteria in space is important for protecting astronauts on long spaceflights, and previous research has shown that bacteria behave differently in the microgravity environment of space. For example, in space, bacteria multiply to higher numbers and in some cases are more virulent and less susceptible to antibiotics. Researchers had previously theorized that this behavior results from the lack of gravity reducing the movement of extracellular molecules and leading to reduced nutrient availability, however, there was little evidence to support this theory.