Ricky Williams is a professional astrologer now

Along with running a cannabis-friendly gym and launching his own brand of marijuana, former Miami Dolphins running back Ricky Williams has been busy studying astrology since retiring from the NFL.

Williams now bills himself as a professional astrologer, offering natal chart readings for $300 a session. He also looks to the cosmos for financial advice, and told CNBC's Tom Huddleston Jr. that astrological transits inspired him to invest in Bitcoin.

"When I look at things, I tend to look at astrology to get insight," Williams said. "The insight that got me interested in Bitcoin was the planet Uranus is about to enter into Taurus."

Williams said Uranus "is about revolution; it's about a change in the way we do things; it's about innovation," while Taurus "is about resources and finances."

So far, Williams has invested $50,000 into the cryptocurrency.

"I didn't want to go crazy," he said.