Will a hammer and a feather fall at the same speed in space?
Yes. Although scientists have been predicting this for centuries, it was finally demonstrated by astronauts in 1971. David Scott, commander of Apollo 15, took a hammer and a feather out onto the Moon’s surface and dropped them together. You can watch the attached video to see them landing at the same time. The only reason feathers fall slowly on Earth is wind resistance. Feathers are very large for their mass (they have a very low density), so experience a lot of drag when moving through the air. A dense object (like a brick, or a hammer) has much more mass, which means it has more kinetic energy which lets it shove the air aside easily. But take away the air, by dropping them inside a vacuum chamber, or on the Moon, and you’ll find them falling at the same speed.