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A "Black Box" For Space Debris?
jonerik writes: "Space.com has this piece on engineers at El Segundo's Aerospace Corporation, who are trying to create a black box - similar to those used in civilian, commercial, and military aircraft - for satellites and other pieces of equipment bound for space, with the aim of trying to figure out why certain pieces of space debris survive reentry largely intact while others burn up in the atmosphere. The box - about the size and shape of a paperback book - would sit dormant perhaps for years and reactivate when a thermal switch senses the temperature rising, signalling reentry. 'Loaded with ultra-small sensors, including accelerometers and a Global Positioning System navigation chip, the box would record the stresses and strains on the hardware during its fall from space.'"
Just attach microjets to the black box and propel it toward the Earth's atmosphere. that way you won't have to wait for gravity to do its work.
Call it spin, tumble, or chaos, an object survives if it is able to spin. This distributes what part of the object heats, and how much damage is done.
Plus objects that spin tend to generate lift, which means drag, which means they slow down quickly after the initial entry.
Homework: go find a 1" x 2" x 30" piece of wood. Grasp it on one end. Out of doors, throw the wood in a level plane, attempting to induce much spin in it (like a boomerang). Make the plane level, and inclined slightly up.
When you let go, that piece of wood will start rolling and spinning, and will generate lift. It'll generate an audible hum, and toward the end of your throw, it'll stop moving forward, but the spinning and rolling will continue. The piece of wood will fall gently down to earth.
We used to play a game of catch with a piece of wood like this in my neighborhood as kids. Some yardsticks work, but they have to be heavy enough, and need to approach being square, but to not actually be square in cross section. (So thin and winglike is bad.)