There is no such thing as "passive" observation: something has to change in order for information to become known. Without a transfer of energy, no observation

There is no such thing as "passive" observation: something has to change in order for information to become known. Without a transfer of energy, no observation can be made, so either we absorb the particle to register that energy (and then it is literally gone after measurement) or we stimulate the particle into emission (drastically changing its quantum state), or we "poke" the particle by throwing things at it (changing its quantum state in the process).