It's time. After weeks of teasing us with talk of his Interplanetary Transport System and images of his new Raptor engine's test firing, SpaceX founder Elon Musk will finally deliver his much ballyhooed speech on Tuesday at 2:30pm ET (7:30pm UK), during the International Astronautical Congress.

Ars has already previewed the speech, which likely will lay out Musk's preferred architecture for Mars settlement, including spacecraft and a large rocket which will be powered by Raptor engines. For the speech to be a success, Musk must go beyond dazzling space hardware. He must prove to us that his plan is not science fiction, but something achievable. Humans have dreamt of going to Mars for decades—one of Wernher von Braun's first public appearances in the United States involved a presentation on Mars exploration to an El Paso Rotary Club. But we have heretofore lacked both the technology and the will to do so.

Musk undoubtedly has the technology, both in reality (such as the Raptor rocket engine or SuperDraco thrusters to land on Mars) and in concept (such as how to transport hundreds of people safely from Earth to Mars). But whether he can build a coalition of support in the government and private industry without undermining NASA's own Journey to Mars is a big question. Tuesday's speech is the start of that effort, and Ars will liveblog the proceedings with a feature-length analysis afterward.

Listing image by Justin Chin/Bloomberg via Getty Images