Astronomers are using computers to make most of their discoveries these days. It's similar in a way to looking for a signal from a galactic civilization, except in this case, they found the signal of sodium, which is one of the easier ones to find. It will be 10 years until NASA can launch its hyperlarge planet-finder telescope, assuming they somehow retain the budget to do so. At that time they will be able to image extra-solar planets, barely.