There is a lot of confusion surrounding Elon Musk’s latest attempt to dominate the headlines, but there are some simple numbers that mean SpaceX is putting a rocket up the commercial side of space travel.

No one seems to know exactly what the music will be that alien’s will hear, if they ever find Elon Musk’s Starman, sitting within a Tesla car, on a rocket, with a certain song being blasted out in loop mode. At one point today, the BBC said it was 'Rocket Man', various media reports say it is 'Space Oddity', but three days ago Elon Musk, the thin white duke of space, said it will be 'Is There Life on Mars'?

The reality, of course is that it will be none of these things.

The most powerful rocket in the world (by a factor of two-fold), but not the most powerful rocket ever - that accolade belongs to The Saturn V, used back in the 1970s - has launched, carrying a Tesla Roadstar, with a dummy wearing a space suit, known as Starman, with a circuit board in the car stating: “Made on Earth, by humans.” The Dash Board has the words “Don’t Panic’, emblazoned on it - so many cultural references: Douglas Adams’ Hitch Hikers Guide to the Galaxy, Bowie music, a ‘space dummy’ named after another Bowie song.

ET won’t get the joke. But the media did, and that created enough publicity to garner the necessary excitement to put the SpaceX funding programme into, as it were, orbit.

Bowie said: “There’s a Starman...he would like to come and meet us, but he’s afraid he’ll blow our minds.”

Musk had a business idea, so gigantic in vision, that he was in danger of being laughed out of the bank, so what do you do under such circumstances? Modesty and understatement was never going to do it. Tell the world you are sending a Tesla into space to meet ET, you are going to colonise Mars within a few years, and maybe investors will believe that your initial, modest by comparison, vision, is eminently achievable.

And for all the PR - Musk may have pulled off one of the greatest PR stunts of all time - the numbers are what really count.

The Musk re-usable rockets cost.

The Falcon Heavy launch is slated to cost $90 million, whereas a comparable rocket launch from NASA is said to cost around $1 billion.

“I love the thought of a car drifting apparently endlessly through space and perhaps being discovered by an alien race millions of years in the future,” said Musk.

The reality is that in 2006, US space start-ups received $2.8 billion, commercial space travel is happening, and Elon Musk is leading the way. He is saying to investors space travel is a commercial proposition and, to quote Bowie, “Let’s Dance.”