Re-entry
Thread Starter
Re-entry
We've just seen a video of ISS crew jettisoning a 55Kg package of garbage to ostensibly burn up on re-entry and it got me thinking, must every lightweight body burn up?
I understand that an object of some mass will take punishment from the energy conentrated on a small point as it decelerates, but what of a large area item of minimal mass like a crisp packet or a piece of tissue paper? Isn't there a point beyond which something with so little mass and such large area ( & thus drag) will be slowed below a velocity that will burn it and so it just floats down?
I understand that an object of some mass will take punishment from the energy conentrated on a small point as it decelerates, but what of a large area item of minimal mass like a crisp packet or a piece of tissue paper? Isn't there a point beyond which something with so little mass and such large area ( & thus drag) will be slowed below a velocity that will burn it and so it just floats down?
Spacex Falcon 9 payload fairings spring to mind. There's a video of one re entering the atmosphere at about 17,000 KMH. A bit of paint burnt off but they intend to use it again.
Found it...
Found it...
This might be a bit of an "it depends", even with the crisp packet you've got to get rid of the orbital velocity so a lot will depend on the object's ability to withstand at least some heating long enough to reduce to it's floating down velocity.
The early balloon satellites such as those in the Echo series were described as burning up on re-entry...
https://en.wikipedia.org/wiki/Project_Echo
The early balloon satellites such as those in the Echo series were described as burning up on re-entry...
https://en.wikipedia.org/wiki/Project_Echo
...but what of a large area item of minimal mass like a crisp packet or a piece of tissue paper? Isn't there a point beyond which something with so little mass and such large area ( & thus drag) will be slowed below a velocity that will burn it and so it just floats down?
