On Friday, SpaceX CEO Elon Musk will be giving a "major" update on his plans to colonize Mars during a presentation at the International Astronautical Congress in Adelaide, Australia. His talk is meant to add to the one he gave at last year's IAC conference in Mexico, when he revealed the full architecture of his plans to send thousands of peoples to the Martian surface. This time around, it seems his speech may revolve around making the concept more feasible — mainly by scaling things down.

Musk has only dropped a few hints about what he'll talk about this week, but we can probably expect the announcement of a smaller launch vehicle, as well as ideas for how to pay for the high costs of developing such a rocket. He's also said there will be a few surprises regarding how the vehicle will be used.

Here's a few points Musk will likely talk about this week, as well as other things we'll keep our eyes peeled for.