If you are a passionate of the space exploration and its colonization ultimately, you may have attended to two events this week: the space bingo of where the Chinese rocket “Long March” was about to crash (which ended happily) and the first successful flight and landing of the SpaceX’s SN15 Starship, this is what we are going to talk today.
Starship is meant to be a fully reusable 2-stage heavy lift launch vehicle. To summarize, it is a rocket capable to land and be re-launched while transporting heavy loads, such as satellites or humans’ expeditions. Up to now it has been needed five high altitude flights until the first complete success, and it is all private.
Although we can think that making it land is only a matter of restarting the engines, it’s not easy at all; to avoid the freefall, Starship performs a controlled fall using its cylindric belly to reduce airspeed by friction; what happens on its interior is that the fuel (liquid oxygen and methane) expands filling their tanks and avoiding a reignition of the 3 raptor rockets. The starship, then, needs a backup methane tanks that push all the fuel to the rockets fast enough to restart them on the crucial moment.
Another problem referred to the re-entry is the heat dissipation. As half of the fuselage is going to be used as an airbrake, the Starship is designed to be half covered by hexagonal tiles such as the Challenger had to fight the heat generated by the friction with the atmosphere at high speeds.
Despite the fact that the Starship conjunction is a 2-stage vehicle, what we have seen being tested up today is only the second stage. The first and booster one is called Super Heavy and is meant to be 72m tall making it the biggest rocket ever built with the addition of the Starship stage. It’s expected that the first full orbital flight will be in July 2021.
The choice of the methane as fuel is selected to fulfill the ambitions or SpaceX and Elon Musk. In fact, Musk wants to go beyond the orbital flights and, more specifically, “go well beyond Mars”. The methane, indeed, it would be easily synthetized from Mars’s atmosphere.
Up to now, Starship has been selected by the NASA to drive astronauts back to the Moon and it’s meant to participate in lot of further missions.