There aren't really enough words that can be said to describe the influence of Ralph McQuarrie on the collective consciousness of people my age. He was brought on to help design the original looks for characters like Darth Vader and Chewbacca in 1975, alongside many of the spaceships and sets. That along would earn him a place among the greatest concept artists of all time, but he of course went on to help with the looks of The Empire Strikes Back and Return Of The Jedi, as well as contributing to such iconic fare as Close Encounters Of The Third Kind, E.T., and Jurassic Park. He won a well-deserved Oscar for his work on the surprise 1985 smash hit Cocoon.
I had the privilege of working with the concept artist who helped create the visual look and feel of the Fallout universe at Obsidian, and it's difficult to overstate the importance of the job, and also the relative obscurity of it. Every video game that you play and every movie that you watch (especially in the sci-fi or fantasy genres) has an artist or two whose job is to set out the visual look of the entire affair, from the main villain to a gun that might be seen in a single shot halfway through the film, and the responsibility must seem overwhelming at times. Needless to say that McQuarrie rose to the occasion many times, and will be missed. Take a look at a very small portion of the scenes which sprang from his head: