SpaceX is ready to send the world's first private space passenger around the moon.
After someone responded to the tweet by jokingly suggesting that Musk himself will be the passenger, the SpaceX CEO offered a hint about the person who is traveling, responding with a Japanese flag emoji.
SpaceX has always been public about their dream of sending private citizens to space.
The first ship carrying crews could arrive two years later, he said. We plan to do that, probably in the fourth quarter of next year (2018).
In June this year, it was reported the mission had been postponed until 2019 at the earliest.
The BFR (also known as the Big Falcon Rocket) is SpaceX's upcoming two-stage reusable spaceship system that will weigh 9.7 million pounds and be capable of taking a 330,000-pound payload to Mars and lower-Earth orbit (LEO).
The company said more details would be made available on Monday.
On its website, SpaceX is touting the "first passenger on lunar BFR mission", implying there will be more. The BFR planned for use in the trip, is still in development.
Musk announced the BFR in 2017 and has since gone on to state that it could be used for a wide array of purposes.
(SpaceX) said in a tweet.
In December 2017, US President Donald Trump also issued a directive to "lead an innovative space exploration programme to send American astronauts back to the moon, and eventually Mars".