My apologies- I skimmed a different article and thought it was announcing a message sent 20 years ago arrived and there was no reply.

You have to wait another 20 years for a reply.... if it's 20ly away something traveling at C will take 20 years to get year... sure they'll have just gotten our signal, but even if they immediately send out a reply it takes another 20 years, idiots.

Nope, he'd have been too blinded to invent them, he'd be lobbying for incandescents while his apprentices would be off developing CFLs and LEDs...