Spacehopper. If you have not heard about it, it is time to feed your inner space geek.
Starhopper completed tethered hop. All systems green. https://t.co/0m5Bm5slD2
— Elon Musk (@elonmusk) 4 april 2019
Elon Musk from SpaceX has never been hesitant to speak about his goals for starting his space launch company early in the 2000’s: the colonisation of Mars and making humanity an interplanetary species.
This probably contrasts somewhat with your more humble life-goals, like world peace and an end to hunger, but it is neat that at least some billionaires spend their money on existentially more important issues like preventing humanity goes the way of the dinosaurs, which, as far as scientist have checked, did not invest in a space program or a dinosaur presence on other planets, and are now extinct.
SpaceX has been promising an interplanetary reusable spaceship for several years now and behind the scenes they have been working on a powerful rocket engine ‘raptor’ for the better part of a decade. With the engines now ready, SpaceX has started testing the upper stage of their rocket vehicle, which is the part that will actually reach orbit.
On paper it is an impressive piece of kit, able to throw and land 100mton on the Martian surface after a trip of 400 Million Kilometers through interplanetary space. The intermediate term goal is to learn to live of the land, create propellant from the Martian air and return to Earth to do it again. These are essential capabilities SpaceX has to develop before colonists can apply to invade Mars. The NASA Space Launch System (SLS) can launch about the same mass into orbit, but cannot be refueled, cannot be reused and cannot land payloads.
Lately, some doubt has even been publicly raised by NASA administrator Bridenstine that NASA contractor Boeing can even successfully complete its rocket given that it has repeatedly delayed its first flight with several years. While the SLS should have flown in 2017 then 2018 and at the latest 2019, Boeing has demanded to delay the flight to 2020 (and possibly 2021). In a thinly veiled attempt to publicly shame Boeing into action, Bridenstine said that NASA should be able to keep its schedules, and is open to seeking for alternative commercial options if subcontractors could not adhere to their delayed timelines. After some muttering by the political support system for SLS, it is clear that Boeing understood the message and has vowed to make an effort to make the 2020 deadline.
In contrast, the SpaceX hopper tests should have demonstrated hovering and landing capability before the end of the summer and a first orbital flight is planned for next year. The fact that SpaceX is able to do this in such a short timeframe is a testament to their ability to rapidly iterate and learn from past mistakes and improve on successes. SpaceX is also in a hurry because they are a commercial entity and need to turn a profit, which is not the case for SLS. This means they actually need to fly their vehicle ASAP.
While MARS is the ultimate destination (and from there the rest of the solar system), SpaceX desires to flex its muscles by delivering payload to the Moon and potentially even deliver high-value cargo or passengers to the other side of the Earth via a suborbital trajectory. Such trips would require only half an hour, dramatically shortening intercontinental travel.
Surprisingly, it is the latter scenario (and not the MARS-thing) which has become the more exotic project. This is because US VP Pence has recently announced a return to the Lunar surface by 2024 (and we have the technology to do this), while antipodal rocket flights flirt with our disbelief about such a transportation system being an economically viable idea.
To doubters, I would say: SpaceX would have built the BFR project anyway, with proceeds from other profitable launches such as Falcon and Falcon Heavy, even in the absence of a clear economic rationale to outside observers. We are dealing with a founder with a philanthropic goal. Philanthropic means ‘man’-loving. And what better way to show your love to humanity, than to give it a credible way to survive any natural catastrophe.