ROBOT GARDENERS BEING DEVELOPED: In a different project, computer scientists engineered small robots that tend to tomato plants. The robots can determine when a plant needs water or when tomatoes are ripe for harvesting- and then follow up by carrying out the necessary action. Sensors in the soil indicate the locations of plants to the robots, and humidity sensors determine the level of moisture in the soil. Once a task is completed, the robots can audibly describe what's been done. A mounted camera enables the robot to report how many tomatoes are on the plant and when it is ready for picking.

WHAT HAPPENS TO A PERSON TRAVELING IN SPACE? The zero-gravity environment of space offers many challenges to astronauts. One of them is bone and muscle loss. With no gravity to pull people down, there's no need to use muscles and bones to hold the body upright. Both systems weaken, which is why NASA established exercise programs for astronauts spending long periods of time in the International Space Station. Despite these efforts, astronauts still lose muscle strength and bone density, which is why they require physical therapy on Earth after lengthy stays in orbit.
