Elon Musk just did a Reddit AMA and answered several questions about his BFR (Big Falcon Rocket) systems. He also revealed technical details about his plans to reach Mars by 2024.
The AMA (Ask Me Anything) was posted under the "space" subreddit and Musk took to answering them in his signature witty style.
One of the most upvoted questions was on how Musk plans to scale up the rocket from the prototype stage that it currently is in and a timeline as to when this scale-up is expected to happen. Musk answered by saying that scaling up a rocket engine is not difficult and that is, "very simple to scale the dev (under development) Raptor to 170 tons (amount of thrust that is needed)".
He continued by pointing out that the focus is on making BFR reliable. "The objective is to meet or exceed passenger airline levels of safety," he wrote. He also wrote that the Earth-Earth spaceship-based travel system between countries that can take people to anywhere on the planet in about 30 minutes will "be negatively affected if 'but also, you might die' is on the ticket."
On the BFR's updated design (the 2016 design is quite different from 2017 one) and the reason for it having "delta wings" and the absence of a tail assembly like an aircraft, Musk responded that, "Tails are lame," after posting a "+1" on a Redditor who guessed rightly that a tail and wing assembly will not be needed for the BFR as it does not "glide" even after re-entry in the atmosphere.
Another question from a Redditor about how Musk plans on building the engines and if he will be 3D printing them brought out some revelations regarding the way the BFR's engines are getting made. Musk answered the part about 3D printing by saying that some components will, in fact, be printed while also saying that his team has come with a whole new type of metallic alloy that has the high strength needed, but also won't burn, adding, "Pretty much anything will burn in high pressure, hot, almost pure oxygen."
A user enquired about the possibility of the internet on Mars and if there are going to be satellites placed in Mars orbit to provide communications. Musk responded that if anyone is interested in doing it, they should start right away.
He added that the distance from Earth to Mars at its shortest is 3 light minutes, "So you could Snapchat, I suppose. If that's a thing in the future."
Musk at his presentation at the IAC spoke at length about making use of propellants from the Martian surface and mining Mars for resources. This process, called "in situ resource utilization" (ISRU) is one of the keys to a successful colonisation effort, pointed out Musk. He mentioned that the designs and technology needed are already underway.
He also promised to provide 4K quality rocket footage in the near future on his YouTube page.
On the illustration he used to explain how a Mars colony would look like, including the buildings and the way the city seemed to be built around the spaceships, prompting speculation around if it will become a permanent feature on the Martian surface, he asked people not to read into it too much.
In a paper Elon Musk published in September 2016, he spoke of making humanity a multi-planet species and last month at the International Astronautical Congress (IAC) he unveiled concrete plans including spaceships and the entire roadmap that outlines details as to how and when humans will set foot on the red planet.
The hour-long presentation included SpaceX's plans for interplanetary travel, Mars colonisation and several other technical details. The idea is to send two cargo ships to Mars in 2022 and in 2024 send four ships, two with cargo and two with human settlers.