We build on the knowledge of those before us. The people who invented the original programming languages are mostly gone and most of us probably don't know how to use the stuff created but future works were based off the findings of those before them and we all benefit from that.
Hubble has been around enough now that the next generation of stellar and space engineers are getting though university and into NASA and other space ventures.
Kids need to see the previous generation has set extraordinary goals to inspire them to set their own goals. What could be more inspiring than a middle school student seeing Hubble launch, being inspired to study and then after college get to participate in what inspired them in the first place.
