Engineering.com interviews Elon Musk, and asks him his opinion on science vs. engineering. He gives the right answer.
Basically, you can’t do the physics without the engineering. While it’s true that engineering is constrained by and reliant upon physical laws, further discoveries in the sciences require engineers (in title or in spirit) to design, build and operate the apparatus for the experiment. This truth applies to the lens grinders who made Galileo’s telescope all the way up to the LHC at CERN and the Curiosity lander, and even further back than that. Behind every great scientist, there’s a great engineer!