 What is likely the reason that Dr. Vincenti left Earth?
But with the Procyon shuttle arriving yesterday, there was no telling what might turn up. For eighty years now, they’d been sending out the little ships that vanished at greater than the speed of light, equipped with every conceivable device to make them return automatically after taking pictures of wherever they arrived. Vincenti was a member and would probably be the quickest to get. He left a year ago to visit a son in the Centauri system. Vincenti had been an oddly morose man the last few times he’d seen him, but that could hardly explain his taking a twenty-year shuttle trip for such a slim reason.
 he discovered the truth about rejuvenation
 he missed his family and wanted to live with them  he wanted to share his newest discovery with a different planet  there wasn't a lot of demand for doctors on Earth  he discovered the truth about rejuvenation