Q: Can you feel the movement of the space station? I’ve often wondered if it sometimes bounces or jostles. Thanks! (Grant in Bradenton, Florida)
That’s a good question, one I haven’t been asked before. While I was aboard the ISS I never felt any motion of the structure, even as the shuttle Atlantis (and later the station gyros) maneuvered the ship to keep it “flying” with its long central hallway parallel to the Earth below. These maneuvers were done to keep the solar arrays in the right position to track the sun and generate electricity. The small rocket firings were not noticeable, and the gyros apply very small, silent torque impulses to rotate the station.
But the station does get a jolt when a Progress or ATV cargo ship docks robotically at one of the docking ports: when the two ships touch docking rings there is a perceptible thump. But because the station has a mass of nearly a million pounds, it would take a pretty sizeable impact (as when the shuttle used to dock) to shake the structure.
Every couple of months the station is reboosted to a higher orbit by a firing of the small maneuvering engines on the Progress cargo ship. The acceleration is nearly imperceptible (no noise), but British astronaut Tim Peake shows us in this video that the change in the station’s velocity is small but noticeable:
To astronauts, 99 percent of the time the station is a rock-solid home, cruising silently around a dazzling planet in a marvelous universe.