Previously, SpaceX founder Elon Musk has said he intends to launch the "silliest thing we can imagine" on the maiden launch of the Falcon Heavy. This is partly because the rocket is experimental—there is a non-trivial chance the rocket will explode on the launch pad, or shortly after launch. It is also partly because Musk is a master showman who knows how to grab attention.
On Friday evening, Musk tweeted what that payload would be—his "midnight cherry Tesla Roadster." And the car will be playing Space Oddity, by David Bowie; the song which begins, "Ground Control to Major Tom." Oh, and the powerful Falcon Heavy rocket will send the Tesla into orbit around Mars. "Will be in deep space for a billion years or so if it doesn’t blow up on ascent," Musk added. Ars was able to confirm Friday night from a company source that this is definitely a legitimate payload.
Earlier on Friday, Musk also said the Falcon Heavy launch would come "next month" from Launch Pad 39A at Kennedy Space Center in Florida, meaning in January. The company may attempt a "static fire" test of the rocket's three cores, and 27 engines, on the launch pad this month. As the Falcon Heavy rocket has been oft-delayed, launch dates should not be taken too literally, but it does seem like the rocket and associated hardware are close to ready to fly.