Just what the title states. An artificial satellite will orbit Earth with some defined angular momentum. An aircraft,on the other hand, relies upon it's engines to provide continuous forward velocity & lift.
I understand the mass of the satellite, shape of the orbit may be a factor here. As also the factors mentioned in dmckee's comment below. To clarify, the intent here was indeed to determine atmospheric drag. Mike & Peter, I proffer my apologies.
How closely may an artificial satellite orbit Earth without decaying appreciably each orbit? Is there a definite formula/formulae to determine this by direct substitution of values, or is each such calculation unique?