This week, astronauts on board the International Space Station (ISS) will activate the Advanced AstrocultureTM plant growth chamber — delivered to the ISS in April by the space shuttle Endeavour. A nutrient solution will inundate a bed of inorganic “soil,” germinating the seeds buried there. Meanwhile, back on Earth, thousands of students will begin growing their own batches of the plant, Arabidopsis thaliana, a flowering weed better known as thale cress. A comparison of the sprouting plants on Earth with those in Earth orbit will help students and scientists understand how plant lifecycles are affected by freefall. Such research is important to the future of space exploration, because plants will likely provide food and even replenish air and water supplies for future spacefarers.