When the red lights go out at the Albert Park circuit in Melbourne, Australia on Sunday (17:00 local time, 06:00 GMT), it will not only mark the start of the 28th Australian Grand Prix but of the 2012 Formula 1 season as well.

It will also mark the first time in the 62-year history of the sport that six world champions line up on the same grid: Michael Schumacher (7 titles), Fernando Alonso (2 titles), Lewis Hamilton, Jenson Button, Kimi Raikkonen (1 title each) and, of course, the reigning champion, Sebastian Vettel, who also won the 2010 world title.

In Formula 1, things can change dramatically from one year to another. And FIA is certainly trying hard to make any advantage held by a single team evaporate: thus it made the standard ECUs even simpler, compelled all teams to use “periscope”-style exhausts eliminating their aerodynamic effect on the diffuser, made changes to the front wing’s minimal strength and height and outlawed ride-height suspension systems.

Despite all these changes, some of which were clearly aimed at Red Bull (and made most cars sport an ugly face), the 25-year old German and the all-conquering these past two seasons RBR team are starting out as the ones to beat.

Which are their biggest threats? RBR team principal Christian Horner comments: “I think McLaren look like they’re going to be competitive, Mercedes look like they’ve made a step forward, Ferrari I don’t think are as in bad a shape as has been perceived and Lotus have shown flashes of speed as well. Out of that, you’ve got four or five teams that all have a chance of being competitive.”

Raikonnen’s return with the Lotus team was probably the biggest surprise, since the 2007 world champion had abandoned F1 in 2008. It will be very interesting to see if the “Iceman” is still in form and if his team, which has shown much promise in pre-season testing, can make the jump to the Tier 1 league.

The same applies for Scuderia Ferrari. Maranello’s lackluster performance was attributed to a car that couldn’t make its Pirellis work as efficiently as those of RBR or McLaren, and it was mostly due to Fernando Alonso’s fighting spirit and driving skills that they managed to net one win and third place in the constructors’ championship.

But the F2012 is a brand new car, and for the most part of the last six decades, Ferrari is always a force to be reckoned with.

As is the team that beat it to second place in 2011: McLaren is the only team to field two world champions in its cars. Of course it has done so quite a few times in the past, the most memorable being the late Ayrton Senna and his nemesis, Alain Prost. Handling two “number one” drivers, and world champions at that, is not an easy task but if any team can pull it off, it’s the Woking-based outfit.

Michael Schumacher, on the other hand, always made sure he was the undisputed number one driver by destroying his teammate in every team he ever raced. Just ask Eddie Irvine (who was quite comfortable, actually, being a highly paid number two) or Rubens Barichello (who clearly wasn’t) to name but two.

Until his return from retirement, that is. He may be 16 years younger and have no world titles or even a single win or pole position under his belt, but Nico Rosberg’s pace has surely given F1’s record-man (7 championships, 91 wins, 68 poles) something to think about the last two years they have been team mates at Mercedes.

Finally, after much fuss, F1 returns to the U.S. on the penultimate race of the season and there are three new teams this year. Well, “new” is actually a misnomer, as all three raced in 2011, too, but under different names: Lotus Renault became Lotus F1 Team, Team Lotus is now Caterham F1 Team (so, no more confusion with the Lotuses), and Virgin Racing has been transformed into Marussia F1.

There are also two rookies, both of them French: 2010 British F3 champion Jean-Eric Vergne, who races with Toro Rosso and Marussia’s Charles Pic, who finished fourth in the 2011 GP2 championship.

So there you have it: 12 teams, 24 drivers, 20 races. Let the battle begin!

PHOTO GALLERY

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