Category: Other Worlds and Tech

On September 28th, 2018, NASA issued its latest report on how it hopes to return humans to the Moon and then travel onwards to Mars. Entitled the National Space Exploration Campaign Report, it’s a bit of a curate’s egg of things; just 21 pages in length, it offers a lot of aspiration, not always with underlying detail; avoids hard decisions while offering open-ended time lines; presents time lines as a road map,  but avoids mention of precisely how to reach the destination(s) or the cost of the journey(s).

In all, the report lays out three broad aims:  expanding low Earth orbit activities to include commercial operators, operating their own orbital facilities – and possibly the International Space Station; moving outwards to lunar orbit and from there to the surface of the Moon; then moving onwards to Mars. All are painted with very broad brush strokes and leave much unsaid.

The lunar aspects of the report, for example, cover the incremental development of the Lunar Orbital Platform-Gateway (LOP-G) and how it could theoretically help develop capabilities that can be used in vehicles intended to carry humans to Mars. It also outlines how NASA can build towards human operations on the Moon through an incremental development of automated capabilities that both increase our understanding of the Moon, the resources it offers, etc., to a point where the first crew-carrying lander vehicle could be ready “in the late 2020s”. But when it comes to detailed ideas for the architecture of a human presence on the Moon, things are left vague.

In terms of Earth orbit operations, the report points to NASA transitioning away from operating the International Space Station to leasing facilities from the private sector; but precisely how these commercial orbital platforms are to be built is unclear, other than referencing the US $150 million of NASA’s that will be used to encourage commercial development of such platforms from 2019. $150 million is a very small amount when you consider the $100 billion construction cost of the ISS; without some very clear-cut, real-time ROI being evidenced for the private sector, it’s hard to see the ISS being supported by multiple commercial platforms of equatable capabilities in just six years.

To be fair, some of the lack of detail within the report is understandable on a number of levels. In 1989, for example, NASA produced the Space Exploration Initiative (SEI), a report outlining how it would take humans to Earth orbit, thence to the Moon and thence to Mars. The report offered a massive vision: 30 years of development and exploration lading up to humans landing on Mars – as a suitable price tag to go with it: US $430 billion. That’s the kind of figure that would have had Congress dropping the report into the bottom of a very deep draw (possibly in a locked filing cabinet stuck in a disused lavatory with a sign on the door saying Beware of the Leopard, somewhere in the basement of Capitol Hill, if I might re-purpose a quote).

There’s also the fact that it’s hard to get any politico to sign up to something that has end results they’re unlikely to be in office long enough to see. This was certainly the case with SEI, and it was something John F. Kennedy understood when he set NASA the goal of “landing a man on the Moon and returning him safely to the Earth” within a decade. Thus, it is perhaps understandable why this report doesn’t stray that far beyond 2024, preferring to leave matters after that date pretty much as “TBD”.

However, in the course of the last few years, NASA has been repeatedly criticised by the US Congress for refusing to present  specifics when outlining its intentions. In this respect, the pendulum seems to have swung too far: from a gung-ho attitude of “gives us the money and we’ll deliver – although it could take longer than you’ll be around” evidenced with SEI, to an almost timid, “We’d like to do this, but we’ll sort out how later, so you don’t have to worry about the price”, which is perhaps as equally as dangerous when trying to set out where you’d like to go and how you’d like to get there.

The View from an Asteroid

In my previous Space Sunday update, I covered the arrival of two small Japanese landers on the surface of asteroid 162173 Ryugu. Since then, both of these little vehicles have been returning images and data as they sit on the asteroid’s surface and / or hop around it.

While the rovers – MINERVA-II1 A and B – have both revealed the surface of Ryugu to be rocky, the images are still stunning, especially those stitched together to form a time-lapse video showing the Sun passing across the sky above rover 1 B as the asteroid tumbles along its orbit.

The rovers are two of four vehicles that will be delivered to the surface of Ryugu by Japan’s Hayabusha 2 satellite, currently orbiting the asteroid. Together the rovers and orbiter will probe and study Ryugu in detail, with the orbiter also gathering samples from both the surface and sub-surface, which it will return to Earth for analysis at the end of 2020.

Continue reading “Space Sunday: roadmaps, space stations, rovers and storms” →

On Monday, September 17th, SpaceX CEO, Elon Musk, provided an update on the company’s massive Big Falcon Rocket (BFR) and Big Falcon Ship (BFS –  previously referred to simply as “the ship” or “the spaceship”), and revealed the first fare-paying passenger who will supposedly fly around the Moon aboard a BFS some time in the 2020s.

BFR has been in development since 2012/13. Designed to be fully reusable, it was initially referred to as the Mars Colonial Transport (MCT) – reflecting the company’s intention to use it to send humans to Mars. In 2016, SpaceX revealed the first formal design for the vehicle, which had been renamed the Interplanetary Transport System (ITS) to reflect the fact it could fulfil a number of roles. At that time, the vehicle  – comprising a first stage booster and upper stage starship – was to be a 12 metre (39 ft) diameter, 122 m (400 ft) tall monster. By 2017, it had been renamed the BFR (for “Big Falcon Rocket”), and redesigned to be 9 m (29.5 ft) in diameter and 106 m (347 ft) tall.

With the 2018 presentation, Musk revealed further design changes to the system, most notably with the upper stage spaceship, the BFS, some of which give it very retro rocket ship look.

Left: The evolution of the BFR from 2016 (as the ITS) to 2018; renderings via the Everyday Astronaut. Right: an animated comparison between the 2017 BFS and the 3-finned 2018 variant (from an idea by Overlook Horizon).

In particular, the BFS now sports three large fins at its rear end. All three are intended to be landing legs – the BFS being designed to land vertically – with two of them actuated to move up and down as flight control surfaces during atmospheric decent. These are matched by two forward actuated canards, also designed to provide aerodynamic control during a descent through an atmosphere.

Two less obvious changes are an increase forward payload section and the design of the nose area of the vehicle, which includes a much larger forward “canopy” design than previous iterations, and an update to the BFS’s motors. Originally designed to be powered by 7 of the new SpaceX Raptor engine optimised for vacuum operations, the BFS will now initially be powered by seven of the same Raptor motors that will be used on the vehicle’s first stage (which uses a total of 31), optimised for thrust in an atmosphere.

Elements of the first BFR system have been under construction for the last 12-18 months. These include one of the fuel tanks, and the initial hull rings, and Musk claims that the company hope to have the first BFS prototype ready for initial “hopper flights” – lifting itself off the ground under thrust and then landing again – by the end of 2019. SpaceX then plan to run high altitude testing of BFS in 2020, together with initial flights of the core stage as well.

Overall, the goal is to have the first BFR / BFS combination ready for orbital flight tests in 2021, building towards the flight around the Moon, which the company has earmarked for 2023.

This is an incredibly ambitious time frame, one most unlikely to be achieved. SpaceX would appear to have some significant engineering challenges to overcome. For example, by combining the landing legs with control surfaces, how are they going to ensure the craft can land sufficiently gently on another surface without damaging the mechanisms designed to move the fins, which will be required when the vehicle returns to earth.

While there was always a risk that landing struts (as were originally going to be used with BFS) might suffer damage as a result of a “hard” landing on the Moon or Mars, integrating landing systems into surfaces vital to the vehicle’s (and a crew’s)  safe return to Earth as planned by SpaceX, would appear to add further complexity to the vehicle – or call for contingencies to be able to transfer a returning crew to another vehicle on their return to Earth orbit should one of systems use to actuate the fins suffer damage when landing on the Moon or Mars.

Another of the questions from where is BFR is likely to be launched. When initially revealed with a 12-metre diameter, it required a purpose-built launch facility. But with the core now reduced to a 9 metre diameter, BFR could in theory be launched from the SpaceX facilities at Launch Complex 39A, Kennedy Space Centre (KSC), Florida.

More particularly is the entire question of whether or not such a behemoth is really commercially viable. Payloads are getting progressively smaller, lighter and more capable;  SpaceX itself is transitioning its Flacon 9 flights to a mix of dedicated launches and “transporter” (more usually called “rideshare”) launch, combining several customers into one launch, thus lowering the cost per customer.

That’s fine for a vehicle with an all-up semi-useable payload capacity of around 15-16 tonnes, it only takes perhaps a third of that capacity to reach the point where the launch is revenue-earning and the lead time for customers seeing their satellites in space is relatively short. But multiply that out to the scale of Starship, ad the lead-time in getting sufficient customers to fill the a vehicle even one-third full in order to lift income sufficiently over launch costs (assuming the new vehicle is as low-cost as Falcon 9) could be a real problem.

In discussing plans, Musk revealed a final decision on BFR launch facilities has yet to be made, and hinted it might even initially fly from a floating platform. This was an idea first put forward in one of the company’s promotional videos for the system, suggesting it could fly up to 100 people between New York City harbour and Shanghai harbour in 40 minutes. This, simply put, will not happen – because the idea doesn’t work either economically or practically.

Continue reading “Space Sunday: Moon trips, Mr Spock’s “home” and roving an asteroid” →