After spotting the signs of exoplanets, Percy was required to keep watching for the signs of orbit and so on. He needed to get someone else to cooperate with him about using a different telescope either on earth or in space as well to verify their existence before writing a paper on it.
The paper would then have to be submitted to a peer-reviewed journal to verify that the research was sound. After it was published, the planets could get added to NASA's official catalogue.
It would likely be a lengthy process. Since graduation was only a couple of weeks away, Caltech made him an offer to stay on as a doctoral student to continue his research. If the new planets were found to be valid, their observatory's telescopes would get the credit and that would look very good for the school's funding.