One university at this year's Utah Cubesat Workshop, is designing a re-entry cubesat.
Talk about the ultimate ham radio fox hunt! Find this pebble somewhere over a few million square miles...
The problem is having a transmitter to survive the re-entry... One figure is that about 300 Killowatt Hours of energy has to be disipated in a few minutes.
Why is it that all re-entries always end in the ball of fire over just a few minutes. Why cannot the re-enetry energy be disipated over a longer period to make it more survivable. Of course, if they could, they would. It appears to be the nature of the beast. You are entering an ever denser medium, so the drag has to escallate and you end up with the 6/7 minute burn.
What if the surface of the re-entry vehicle radically changed during the re-entry phase? As the density of the atomosphere increased, the surface area decreases. An ablative system that instead of burning off a thin skin of material as in most re-entry systems, you planned on burning off 95% of the original drag volume? What re-entry profile could be achieved Could we make a golfball core "pinger" that could survive?
With the cheap $8k launches and only 3 month mission life, this idea of concentrating on making an interesting mission at the re-entry phase is a new opportunity..
The ultimate fox hunt?
Bob, WB4APR