"Aims are statements of intent. They are usually written in broad terms. They set out what you hope to achieve at the end of the project.
Objectives, on the other hand, should be specific statements that define measurable outcomes, e.g. what steps will be taken to achieve the desired outcome."
It's all a bit vague, really, ie getting a job as an archaeologist is just as measurable as getting an archaeology degree.
If you aim to become a professional - that is suitably vague, while getting a degree, one route, is more specific.
I do like this from TeeDee: "Aim is what you take to hit the Objective."