In a 40-minute speech at the International Astronautical Congress in Adelaide, Australia, Elon Musk unveiled his ambitious new plans for his rocket company SpaceX. Make that very ambitious. SpaceX plans to land an unmanned spaceship on Mars in 2022 that will start preparing an environment for human visitors to arrive two years later. In the meantime, and partly to fund the endeavor, the BFR (Big F&%$ing Rocket) will whisk people from one earth city to another in less than an hour by traveling above the Earth's atmosphere. It seems far-fetched, but then Musk has already succeeded at several seemingly impossible projects. So it's no surprise that his grand plans made headlines around the world.

But his speech got attention on social media for a different reason--his awkward, stammering delivery.

Musk is an unpolished public speaker at the best of times, but in this presentation he seemed more challenged than usual. He mumbles through the important phrase "multi-planet species" so fast that it's difficult to hear correctly. Here's a fairly typical sentence from early in the presentation: "This is the updated design for the, the...well we we're sort of...searching for the right name, but the code name at least is BFR." The next one is even worse: "Um...and...I...the the the the...probably the most important thing that I want to convey in, uh, in this presentation is that I think we have figured out how to pay for it."

The Twitterverse reacted with understanding and affection:

Other tweeters reacted similarly, saying that watching Musk made them feel better about their own sub-par speaking skills.

And yet. Though it's less than 24 hours old and takes 40 minutes to watch, the video of Musk's presentation has been viewed well over half a million times. We watch him because he's Elon Musk, a real-life version of the billionaire genius inventor that's a comic book staple, and because we can't wait to see whether he really will take humans to Mars or bore an underground conveyer-tunnel where cars can be quickly transported from one end of town to another, bypassing traffic.

Even though you're not Elon Musk, there are valuable lessons you can learn from his terrible speaking skills and the fact that his presentations are riveting nonetheless. Here are a few of them:

1. Say why.

Musk's grand plans--humans on Mars in seven years!--are compelling enough on their own, but in every presentation he makes sure to begin by explaining why what he's planning is truly important. Before unveiling the eagerly awaited affordable Tesla Model 3, he reminded the audience of the dire and worsening problem of CO2 in the atmosphere. Before detailing SpaceX's plans to go to Mars, he talked about becoming a space-bearing civilization and multi-planet species not only as a way to help ensure humanity's survival but also as a way to be inspired by the belief in a future that will be better than the past. "I can't think of anything more exciting than going out there and being among the stars," he said. "That's why."

2. Don't talk down to your audience.

Many wonderful speakers are riveting but seem to be talking to their audience from a higher plane of existence. Steve Jobs was a great example of this approach. Musk seems infinitely more approachable, and only partly because of his occasional stammer and unassuming style. Musk does not present you with a beautifully finished product and invite you to drool over it as Jobs did. He's more reporting peer-to-peer what he and his employees have been up to for the past year.

Take the huge cryogenic oxygen tank that holds 1,200 tons of liquid oxygen, made from a new ultra-strong carbon fiber substance. "We successfully tested it up to its design pressure," Musk says, just as the tank on the presentation slide explodes. When the audience bursts out laughing, he continues calmly, "Then we went a little further. We wanted to see where it would break and we found out. It shot about 300 feet into the air and landed in the ocean."

3. He's completely authentic.

One reason people are so passionate about Musk and his projects is because he so obviously feels deeply about them himself and he doesn't hold back from letting those emotions show.

It's a common reaction, and one that benefits Musk enormously. You can create that same reaction in your audience too, if you're willing to be as down-to-earth and as vulnerable, and let your true feelings show the way he does.

Do that, and you can inspire people to follow you everywhere. It won't even matter if you stammer.