Robert Downey Jr. has something new on the horizon.

In a cryptic video on Twitter, the Marvel Cinematic Universe alum teased an upcoming announcement. "I am bubbling with anticipation," he said. "My gosh! I have inside me a riddle that I have to share. What do the Rolling Stones, NASA and the Rose Bowl and the ruling planet of my birth sign [Taurus] all have in common?"

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"Folks used to say to me, 'How do you keep an idiot in suspense? I'll tell you tomorrow.' Well, you don't have to wait!" he added. "Because it will all be revealed tonight. Oh my god. This may be the most exciting thing I've ever done! I wouldn't miss it for the world."

The video, which sets Downey Jr. against a galactic background, offers no further information.

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Notably, the Rolling Stones are performing a concert tonight in Pasadena, CA. Since Downey Jr.'s mysterious announcement will also be revealed tonight and has to do with the Rolling Stones, it seems fair to say he may appear at the concert. This certainly wouldn't be the first time he has sung on stage; in 2011, he performed a cover of the Police's "Driven" in honor of Sting's birthday.

However, what all this has to do with NASA and the Rose Bowl remains to be seen. The Rose Bowl is slated to take place on January 1, 2020, about four months away from the present date. Likewise, the NASA part of the announcement may have something to do with the Footprint Coalition, his clean Earth initiative, which he announced at at the Machine Learning, Automation, Robotics and Space (MARS) conference in June. The Coalition will launch in April 2020.

Stay tuned with CBR to learn more about Downey Jr.'s next project as more information becomes available.

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