U.S. aerospace manufacturer SpaceX is planning to fly a private passenger around the moon on one of its spacecraft, the company said in a tweet.

In a messager on twitter on Thursday, SpaceX announced that it "has signed the world's first private passenger to fly around the Moon aboard our BFR launch vehicle — an important step toward enabling access for everyday people who dream of traveling to space."

"Find out who's flying and why on Monday, September 17," it added.

The BFR, or the Big Falcon Rocket, is SpaceX's upcoming two-stage reusable spaceship system that will be capable of taking a 330,000 pound payload to Mars and lower-Earth orbit LEO. It will eventually replace SpaceX's other launch vehicles, the Falcon 9 and Falcon Heavy, as well as its Dragon spacecraft.

Given that the BFR has yet to be built, the around-the-moon trip presumably is at least a few years off, according to the CNBC.

When asked about the identity of the passenger, SpaceX CEO Elon Musk responded on Twitter with an emoji of the Japanese flag, leading some to believe it might be SoftBank CEO Masayoshi Son.

SpaceX's mysterious passenger won't be the world's first space tourist. American engineer and multimillionaire Dennis Tito, who was the first non-astronaut to travel to the space, paid 20 million U.S. dollars to spend eight days on the International Space Station in April 2001.

The seventh and last space tourist was Canadian businessman Guy Laliberté, who flew to the ISS aboard the Soyuz TMA-16 in 2009.