Joe Rogen recently interviewed Elon Musk, which comprises a talk of almost three and a half hours. We will break this interview down into a series of articles in the coming two days, so as to allow readers to go through everything Musk spoke to Rogen.
Joseph James Rogan is an American comedian, podcast host, and commentator. He hosts a show called the “Joe Rogen Experience”, and just yesterday, he released this three and a half-hour-long interview. In this article, we will cover excerpts from the interview related to the Starship, trips to Mars and alien life.
Starship – The SpaceX Dream
While many know Elon Musk as the current CEO of Tesla, he also heads the aerospace company SpaceX. SpaceX was in the news recently for becoming the first private company to collaborate with NASA (National Aeronautics and Space Administration) to send a manned spacecraft to the ISS (International Space Station). While they are working on a number of missions, such as using the Falcon 9 rocket to send satellites into space, the main vision is to launch the Starship system.
The Starship system is basically a proposed fully reusable, two-stage-to-orbit super heavy-lift launch vehicle under development by SpaceX. The system is composed of a booster stage, named Super Heavy, and a second stage also referred to as “Starship”. This proposed spacecraft is approximately 122 metres tall and has a diameter of roughly 9-10 metres.
Currently, the Starship is under testing, and there have been quite a few test launches carried out recently. A number of the rockets that are part of the Starship system have exploded when trying to land, and Musk explains the reason behind that. He says that since a number of different systems such as the rocket body, the engine and the avionics are undergoing changes simultaneously, it gets harder to understand the reason behind the failure. He does mention that the production of all these systems is much harder than their initial designs. Since this is still a test program, he expects a few rockets to blast.
Joe asked Musk what is the expected timeline for starting regular orbital flights using Starship. Musk replied that 2023 is a very achievable timeframe, although SpaceX is trying to launch a few missions this year as well.
Features of the Starship
The Starship is expected to be one of the biggest space vehicles ever built. It will have around 5000 tons of load at liftoff, which means it will require high thrust. To be more precise, it will require more than twice the thrust of the Saturn V. The reason for this is that the Starship will be the spacecraft that will eventually frequent flights to and from Mars. Since Mars is definitely a long way away, the requirements of the rockets change accordingly.
In order to reach Mars, SpaceX will require a highly reusable rocket. Currently, they are experimenting on the reusability of the engine, thrusters as well as payload fairings. Reusable rockets are the Holy Grail of aerospace according to Musk. He says it is easy to go to space, but harder to get into orbit. When you are launching satellites on your rocket, it is important to get into orbit. And in that case, you need a very powerful heat shield on the nose cone of your rocket.
The Starship has two stages, which is the minimum for a rocket for Earth’s atmosphere. In the Falcon 9, the engine, thrusters and payload fairings are reusable. But the top half of the Falcon 9 burns off during re-entry. While SpaceX can avoid this, it will hamper the amount of payload you can take into space.
Specifics of the Heat Shield on the Falcon 9
Most rockets use ceramic tiles on the front end of the rockets to protect the metallic portion during re-entry into the atmosphere. SpaceX also uses ceramic material, mainly consisting of silicon oxides, aluminium oxides and carbon. The geometry is hexagonal tiles joined together at what is known as expansion and contraction joints. The huge changes in temperature during re-entry causes ceramic tiles to expand and contract. Now if the gaps at these joints are too large, then during expansion, the plasma will seep in and destroy the metallic portion such as the engine and the loads. Conversely, if the gaps are too small, the contraction will cause the tiles to crash into each other and crack. Hence, a perfect amount of gap is required.
Alternative Methods of Rocket Propulsion
Joe asked Musk if he sees any other methods of propelling rockets in the recent future. Musk replied that in the future, everything will be electric, but not rockets. And the simple explanation behind it is Newton’s third law. ‘Every action has an equal and opposite reaction’. Cars have an opposing force in the form of friction, ships have opposing force in the form of the waves and aeroplanes have wind acting against them. However, in space (vacuum), there is nothing that can oppose the motion of the rocket externally. Hence, all the effort to move the rocket has to be from the inside.
In layman’s terms, rockets shoot out small quantities of gas at high velocities. In order to conserve momentum, the rocket, which has a higher mass, moves in the opposite direction at a slow speed.
Trips to Mars: An Achievable Vision, But Not Immediately
Talking about Starship, the topic of Mars trips is bound to come up. Musk says that a Mars trip will be possible in the future, but it is hard to approximate a timeline because of a number of factors. It will take a lot of time to build a civilization on Mars because the absence of the smallest of things will lead to eventual doom.
A Trip to Mars takes almost six months, and Musk gave the reasoning behind this. The strategy of propelling the rockets into space towards the orbit of Mars has to be calculated carefully. It is done in such a way that the rocket has just enough velocity to escape Earth’s orbit and catch Mars’ orbit at the apex. This can be done only once every two years, and so, there won’t be regular trips from Earth to Mars. The specific timeframe is dependent on the speeds of revolution of Earth and Mars around the sun. Musk did mention that it is possible to shorten this journey from six to three months, but that could add the risk of missing Mars’ orbit entirely and move towards Jupiter.
Existence of Alien Life
Musk quotes Carl Sagan when it comes to the existence of alien life – “Either there are a lot of aliens or none at all”. Both of these propositions are dangerous, according to Elon. If there are a lot of aliens, then it could be dangerous for human life. We might be like bugs for them, and they could carry out fumigation. If there are no aliens, it is possible that they got wiped out while trying interplanetary travel.
All in all, researching on aliens is a waste of time for Musk. If there are, in fact, aliens existing and they come to Earth, he’ll be the first one to try and research about them. But until then, he is pretty sure that alien life doesn’t exist. Of course, if any new evidence comes to light, he may change his mind. For example, finding a one-cubic-inch piece of titanium inside the pyramids. Obviously, titanium did not exist at the time when the pyramids were constructed, so that has to be the work of aliens.
Stay tuned for more of these articles, where we’ll be discussing more about the different topics Musk discussed with Joe Rogen.