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The summer of 2019 saw the 50 year anniversary of the Apollo 11 mission, when humans first walked on the surface of the Moon. Engineering and technology surged ahead, thanks to a two horse race between USA and the Soviet Union, where the latter seemingly had the lead in every area. That battle was fueled by suspicion, fear, and a drive to be ‘better’ than the other country. But like all sprints for the finish line, the pace couldn’t last and the urgency soon passed. But now there is a new race — not of countries, but one fought by companies. Capitalism, growth, and business opportunities are the new fuels, and the goals are even bigger: not just back to the Moon, but on to Mars and beyond.
A recap of the last space race
What exactly is a ‘space race’ though? In this day and age, rocket launches, carrying satellites into space, take place nearly 200 times every year and multiple spacecraft operate on or around other planets in our solar system. So the notion of having a race in or to space might seem rather odd, but if we go back 60 years into the past, the situation was very different.
In this day and age, rocket launches, carrying satellites into space, take place nearly 200 times every year
Only two countries really had the capability of launching anything into space: the United States of America and the Union of Soviet Socialist Republics (better known as the Soviet Union). The first known man-made object to reach space was a German V2 rocket, launched by Nazi Germany, in the latter days of World War 2, circa June 1944. There was no scientific goal behind the test; it was a purely military exercise, reaching an altitude of 109 miles (176 km) before falling straight back to Earth.
The technology behind the V2 was utilized by both the US and the Soviet Union, after they snapped up scientists, engineering technicians and technical blueprints at the end of World War 2. The US achieved their passage into space using the German design with the Bumper rocket program, 4 years later, with the USSR achieving the feat just a few months afterwards.
A quick word, though, needs to be said about where exactly the boundary line for space is. The US Air Force and NASA, for example, both set this at an altitude of 50 miles (80.5 km), whereas the FAI (a global organization that records feats in air and spaceflight) uses Theodore von Kármán’s theoretical definition for the start of space, around 62 miles (100 km). At either altitude, the atmospheric density is very low: 99% of the Earth’s atmosphere is beneath this region, so winged flight is essentially impossible.
Just getting to space wasn’t the main interest of the two countries, as they were aiming to achieve orbit. With this, they could place objects that could quickly circumnavigate the planet, out of reach of any fighter plane, to take images or deliver a weaponized payload. In other words, it was a military race and by the 1950s, conflicts in Korea and Vietnam, along with a huge growth in nuclear weapon testing and increased political tensions between the USA and USSR, drove a desperate urgency into the race.
The critical turning point in all of this was the USSR’s launch of Sputnik 1 – the first artificial object to complete a full of orbit of our planet. It actually did over a thousand orbits, before atmospheric drag brought it back down, but for 3 weeks, the 180 lb (85 kg) satellite emitted a simple radio signal, telling the world ‘here I am’.
The space race had truly begun.
The Soviet Union then went on to achieve a number of sizable ‘firsts’:
Now it might seem that America was just sitting back and letting someone else take all the glory, but in a similar period of time (the 1960s), they developed the first solar powered satellites; the first communications, satnav, and weather satellites; they also reached Mars first (USSR reached Venus a few year beforehand) and carried out the first orbital rendezous and docking.
The true finishing line for the first space race was arguably the Moon, though. When the Soviets reached our natural satellite (and by reached, we mean impacted at over 7000 mph), it became the obvious target to aim for, not only for military reasons but for a permanent place in history. In May 1961, President John F. Kennedy delivered his famous speech to Congress, with the immortal line:
“I believe that this nation should commit itself to achieving the goal, before this decade is out, of landing a man on the moon and returning him safely to the earth.”
Since this was said just one month after Yuri Gagarin said ‘Poyekhali!’ and circled the Earth in space, it must have come across as being almost impossible to accomplish within just 9 years; and yet, as we all know, it was achieved with 5 months to spare.
Thanks to that presidential goal, the drive and commitment of thousands of scientists, and a healthy stack of dollars, the Apollo space program introduced a raft of new engineering developments — notably in computing, materials, and rocket technology. So to set the scene for this article on the new space race, let’s have a quick look at those.
The new technology of the old guard
The late 1950s and early 60s was the dawn for the digital computer — mechanical and analogue systems were in use before and during this era, but they either lacked the required processing capabilities for managing a complex rocket system, were too fragile to be depended upon thousands of miles away in space or they were far, far too big to be used in any spacecraft.
Fortunately for the Apollo program, monolithic integrated circuits (aka a chip) had been invented just a few years earlier, and the pace of their development was such that they could be manufactured with sufficient quality and enough quantity to be used to form the basis of the computers to manage the guidance systems of the rocket.
In the early to mid 1960s, researchers at the Massachusetts Institute of Technology, used the new invention to create a computer that was powerful (roughly 85,000 operations per second), compact (just 70 lbs or 32 kg in weight), and very reliable. It may seem utterly archaic by today’s standards, but it was perfect for NASA’s requirements and was used for nearly 10 years on multiple missions. It was formally called the AGC, Apollo Guidance Computer.
The operation and output display of the computer was handled via a separate unit, called the DSKY (display-and-keyboard); inputting a program was done using just two commands (verb and noun), and associated numbers. This simplicity was its strength: astronauts could receive new programs from ground control, quickly enter them, and not have to worry about the fact that they weren’t cutting edge computer scientists.
Multiple ‘cores’ aren’t a new thing
All computers need memory, of course, and the AGC was no different – it had read-only storage (ROM), for holding the operating software, in the form of core rope memory. Think of this as being like a hand woven rug, where thousands of strands of wires are wrapped around or fed through little metallic loops.
These loops, called cores, are part of a circuit component called a pulse transformer and depending on how the strands were woven about the cores, the transformer would generate a null output (0) or a square wave output (1) – i.e. each core was essentially 1 bit of storage.
The AGC that controlled the Apollo 11 spacecraft had 540 kilobits (36,864 sets of 16 cores – 15 for data, 1 for parity checks) of ROM and all of the software, designed by the MIT scientists, was meticulously manufactured by teams of highly skilled women at Raytheon’s factories.
In addition to the ROM, the AGC also had a small amount of re-writable storage, just 30 kilobits of magnetic-core memory. Similar in structure and operation to core rope memory, this basic but dependable RAM used electromagnetic induction within the cores to generate the 0 and 1 values for each bit.
In contrast to the cutting edge technology employed to control the flight systems on the Apollo space, the Soviet Union employed electro-mechanical systems, such as their Globus IMP navigation unit. This ‘clockwork’ computer was surprisingly sophisticated, and remained in use (albeit with significant revisions along the way) for almost 40 years.
It’s worth noting that, unlike NASA’s AGC, the Globus machine did not directly control the spacecraft. Early space missions by the Soviet Union were automated and/or controlled from Earth — the cosmonauts were literally along for the ride. However, the spacecraft only remained in radio contact with mission control for a fairly small period within each orbit, and the gear-driven Globus computer provided a robust system to help maintain correct position and provide the crew with the information needed to alter their position, if required.
Computers back down on Earth
The breakthrough use of computers wasn’t just for controlling the rockets. Back down on terra firma, NASA used the latest machines from IBM to process data sent back from the missions and for the first landing on the Moon, it was a collection of System/360-91s that ran the number crunching.
These were truly remarkable machines – capable of handling 32 bit integer and 64 bit floating point operations, at up to 16 million calculations per second, they were among the first machines to do deep instruction pipelining and out-of-order execution. The system memory ranged from 2 to 4 MiB in size and had multiple memory channels to improve read/write performance.
Ground control computers in the USSR were just as advanced. At around the same time that NASA was employing IBM’s supercomputers to full effect in the Apollo program, the Soviet Academy of Sciences designed and built a machine (the BESM-6) that had a parallel instruction pipeline and 48 bit floating point processor (integer operations were handled by the same units).
While it didn’t match the System/360, in terms of clock speed and memory (address bus was only 15 bits wide, compared to IBM’s 21 bits), it was still a very capable computer – so much so, that they remained in use, like so much of early Soviet technology, for nearly two decades.
The rate of progress in computer technology relegated these machines to history in just two decades (for example, Intel’s 80486 CPU released in 1989 could handle up to 20 million instructions per second and address 4096 MiB of RAM), but that the fact that smartphones of today have capabilities engineers in the 1960s could only dream of, owes no small thanks to the hectic research and development by the US and the Soviet Union.
Materials for man and machine
Digital electronics wasn’t the only area that saw development and progress. To complete the 8 day mission to the Moon’s surface and back, the crew required 3 spacecraft and 3 rockets. In the case of the former, they were the:
- Apollo Command and Service Module (CSM) – this was home for the astronauts during the flight, and also housed the hydrogen and oxygen needed for air, water, and electricity
- Apollo Lunar Module (LM) – the machine that took Neil and Buzz onto the Moon and back into orbit
- Apollo A7L – the self-contained spacesuit for walking on the Moon
It might seem a little odd to consider the spacesuit in the same light as the CSM/LM, but they served a very similar function: keep the crew alive in space. They comprised multiple systems, with layers for cooling — in direct sunlight, temperatures on the Moon can reach 250°F/120°C — protection against micrometeorites and the rough lunar rocks, and a pressurized vessel to cope with the lack of atmosphere.
The complete suits were designed and manufactured by International Latex Corporation (ILC), a firm who specialized in products using polymer and silica materials. The A7L used the full gamut: latex rubbers; polyethylene terephthalate fibres; polymide films; nickel and chromium alloys; polycarbonate shells; gold plated polysulfone layers.
It shouldn’t come as a surprise to note that NASA and the various manufacturers went to on to form commercial agreements, many of which formed products that we know and use even today.
The A7L was such a success for ICL that the overall structure is still in use, albeit heavily modified for the current requirements of missions on board the International Space Station.
Specialized materials were used throughout the construction of the Saturn V rocket, too, involving a wealth of aluminum, titanium, and steel alloys. There were 3 stages in total: the first, using refined kerosene and liquid oxygen for fuel, would run for just 2 minutes but it would be enough to get the rocket up to a speed of 5,000 mph.
The second stage was smaller and less powerful, burning through liquid hydrogen and oxygen for 6 minutes, to boost the velocity by another 10,000 mph.
The final stage, similar to the second one, was used to put the rocket into Earth orbit and then again to head off to the Moon.
Fully fueled, the entire structure weight in excess of 6 million pounds (about 3,000 metric tonnes) and stood 363 feet (111 metres) tall. It still holds the record for the largest and most powerful rocket ever constructed.
The vastness of the Saturn V belies the fact that weight was crucial to the operation of the Apollo program, such that the Lunar Module had a dry mass of less than 10,000 pounds (4,500 kg) and in places, the composite materials were no thicker than the walls of a soda can. The design criteria for safety was essentially not ‘safe no matter what’ but ‘just make it safe enough’.
The Soviet Union had also developed a massive rocket, simply called the N1, although it wasn’t quite to the same scale as the Saturn V. The first 3 launch attempts all ended in failure and the whole project was fraught with in-fighting, battles of egos and politics, and a dearth of proper funding.
When the Apollo program came to end in 1972, USSR engineers tried in vain for a few more years to make a success out of the rocket but it was scrapped without fanfare by 1975.
The Moon: Too far, too expensive
Emboldened by the achievements of their engineers during the 1960s, NASA planned for multiple new programs post-Apollo, including permanent space stations and a base on the Moon, reusable vehicles and nuclear rockets, and a manned mission to Mars.
These were presented to President Nixon and his administration in the early 1970s and the decision was a clear ‘no’ to all bar the reusable vehicle. Any hope of returning the Moon, in an Apollo v2.0 program, was categorically shot down.
The reusable vehicle project would eventually go ahead and become the Space Shuttle program (a temporary space station was also agreed in the form of Skylab), but one thing was clear: there would be no money to putting humans further than Low Earth Orbit, let alone for aiming for a landing on another body.
The Apollo program cost 25 billion dollars by 1973 (at least 5 billion over the 1961 estimate and more than double that of the initial projections) and took up almost half of NASA’s budget each year. To understand just how much money this was, consider the fact that the US federal budget for the year that man first walked on the Moon was around 180 billion dollars.
Spending at that level was never going to be sustainable, and neither the US nor the Soviet Union could afford to tackle the dream of having humans living on the Moon or Mars. Space flights needed to become far more cost effective, especially compared to Apollo, where each flight mission cost in excess of 300 million dollars, covering the craft, fuel, staffing, etc. (valuation circa 1974, $1.5 billion in 2019 dollars).
Each Saturn V rocket was essentially unique, they weren’t designed to be mass-manufactured, and every one accrued numerous revisions to resolve issues experienced in previous flights. No part of the rocket was reusable either; the only part that returned to Earth was the Command Module, and they never saw service again after the mission.
NASA pinned the hopes for making spaceflight routine and profitable on the mostly reusable Space Shuttle (only the main orange fuel tank was wasted each flight); the Soviet Union and then after the collapse of the old state, Russia, briefly experimented with a copy of the Shuttle (called the Buran), but neither met the lofty goals of having a spacecraft that could be used over and over. The failures were either due to fundamental design issues, operating costs, or a lack of funding for development.
Russia abandoned its Buran program in 1993, and NASA retired the Shuttle fleet in 2011, where by that point each mission was costing over 400 million dollars. However, satellite and space probe launches, along with trips to the International Space Station, have become routine, thanks to the many American, Russian, and European launch systems now in operation. The expense is still astonishingly high, though, and all of the rocket platforms used remain non-reusable in any way.
Well, that was the case, up until two years ago.
A new race begins
On a pleasant Thursday evening, in March 30, 2017, a rocket was launched from Kennedy Space Center Launch Complex 39, carrying a geostationary communications satellite.
Two things were special about that launch and both were about the rocket: first, the first stage had been used to launch something into space before and secondly, once it had deployed the satellite into orbit, the same stage returned to Earth and landed on a autonomous platform, just off the coast of Florida in the Atlantic Ocean.
This was no top secret military mission or an experimental machine from NASA; it was a Falcon 9 FT launch vehicle, designed and manufactured exclusively by SpaceX. This private organization, conceived and founded by Elon Musk using funds raised through earlier enterprises (Zip2 and X.com, which eventually became PayPal), was barely 16 years old at the time.
SpaceX’s first rocket launch into low Earth orbit had taken place just 6 years earlier and while it can be said that the company has stood on the shoulders of NASA and Russia, to paraphrase Isaac Newton somewhat, their pace of development and level of flight success has been meteoric.
Musk had set its sights on re-usability right from the very beginning of SpaceX, to drive costs down and maximize revenue. But unlike NASA’s approach for the solid fuel rocket boosters used in this Space Shuttle program, the engineers at SpaceX envisioned a more radical approach.
The Shuttle’s boosters were designed to provide the majority of the launch thrust required and once ignited, they would burn until almost empty. At that point, they would be ejected away from the Shuttle, continue to burn until empty, and then free fall back to Earth.
The boosters would then deploy parachutes to slow the descent rate, before splashing down into the Atlantic Ocean. Bereft of fuel, they could float quite easily, so they would remain at the surface, until collected by a ship.
For SpaceX, this wasn’t good enough, especially since the Shuttle boosters needed to be manually recovered and then required a significant amount of work to be ready for another launch.
What they wanted was a rocket that had engines with multiple capabilities (thrust vectoring, throttling, and a restart function were priorites) but without the costly servicing that the Shuttle’s engines required.
They also wanted the rockets to fly themselves back to Earth, landing on a structure such that they could be recovered with the minimum of hands-on intervention.
And so the Falcon rocket was born. Version 1 took its first flight in March 2006. Like so many attempts before it, the little Falcon 1 rocket failed just 40 seconds into its maiden journey, impacting the ground a mere 250 feet away from where it had set off.
You could be forgiven for thinking that, after 50 years of launches, the task of designing and building a new rocket would be a relatively straightforward process. But space-worthy rockets are machines that tread a desperately thin line that separates them from being classed as commercial vehicles or highly expensive explosive devices.
The design goals of Falcon, and indeed any rocket that can do the same feats, is very different to those that are in general use. You can get a sense of this by balancing a long pole on your fingertips — to keep it upright, you’ll need to constantly move your hand about, although it’s easier if you constantly push upwards.
Once a normal rocket has reached its desired altitude — achieving that through a constant balancing act of upward thrust — and deployed its payload, then the flight is over. For a Falcon rocket, that’s only half the journey: it needs to fly back to Earth.
The returning stage needs to be as light as possible and have aerodynamic control during the return trip. The Saturn V rocket was essentially an aluminum alloy construction, which was considered too heavy, so Falcon uses an aluminum-lithium alloy – this choice of material presents its own difficulties, but its increased use in the entire aerospace industry has helped resolve the majority of them.
Control of the rocket during the return flight is managed through the use of the main rocket, small thrusters, and aerodynamic grid fins as shown below.
These are kept tucked away during launch, and then fold out when coming back down. Initially made from an aluminum alloy, SpaceX switched to a titanium alloy, as they found that the earlier choice only just coped with the thermal stresses of supersonic flight through the atmosphere.
You can get a sense of what the return journey is like in this video from SpaceX, captured via an onboard camera, located at the very top of the rocket stage:
All of this is controlled by computer systems on the rockets. Given the speed and complexity of the landing, you’d be forgiven for thinking that bespoke, cutting edge technology is used here, too. While we don’t know exactly what systems SpaceX are using, we do know that the processors are dual core and x86 in nature, suggesting that the chips used are ‘off-the-shelf’.
The computers run a Linux-based OS and use software developed entirely in house. They are also set in multiple groups, to protect against problems caused by radiation and hardware failure. Modern digital electronics are sensitive to ionizing radiation, and there are two ways to combat this: radiation hardening and radiation tolerant.
The former requires the chips to be uniquely manufactured in such a way that they are much thinner than their domestic cousins — a thinner chip is less likely to absorb penetrating radiation than thicker ones, but the process forces restrictions on how complex the chip can be and adds considerably to the cost.
A radiation tolerant system skips this entirely, using three sets of processors for every onboard computer system, so if radiation affects the calculations of one of them, the other two will produce identical results to each other but different to that affected by the radiation. The software picks this up and everything carries on accordingly.
Where everything on the Saturn V rockets could be manually controlled, either via the crew or by ground control, all of SpaceX’s machines are designed to be fully autonomous – the only time humans step in is if something goes wrong or they need to give final approval before an action commences.
This is the case with the Dragon cargo vessel, when it comes to docking with the International Space Station. The whole flight is managed by the craft itself but it holds from the final docking maneuver until the ISS crew give the signal.
SpaceX has come a long way in 20 years and has shown that there is still lots more scope for the development of rockets.
There’s more than one horse in this race
Elon Musk isn’t the only James Bond villain lookalike that’s loaded with cash and ambitions in space. Born to a total lack of fanfare, Blue Origin was formed by Amazon’s Jeff Bezos in 2000 but was launching test rockets of their own design within a mere 5 years of inception.
The two companies couldn’t be more different if they tried: SpaceX is always ebullient, delighting in theatrics; Blue Origin, on the other hand, has been far more secretive and cautious over the years. In total, SpaceX has achieved over 80 launches, whereas Blue Origin has barely reached 11 in a similar period of time.
SpaceX, however, is more than 3 times the size of Blue Origin in terms of staff, and despite the huge sums of money Bezos has personally committed to the company, the smaller organization has received significantly less external investment and almost no launch contracts. This hasn’t stopped Bezos’ team from exploring new technologies, especially when it comes to the rocket engines.
The various launch systems in use today generally use one of three fuel types:
- Cryogenic liquids, e.g hydrogen with oxygen or refined kerosene with oxygen
- Hypergolic liquids, e.g hydrazine with nitrogen tetroxide
- Solid materials, e.g. aluminum with ammonium perchlorate, bound in butadiene
Each type has its own benefits and disadvantages, and analyzing these would be a full article in itself, but Blue Origin have gone with a combination of liquefied natural gas (LNG) with liquid oxygen. This is the second cleanest burning fuel system, after liquid hydrogen, but its main advantage is that the engine itself requires less complexity than the other liquid fueled systems.
This simplicity translates into lower costs and cheaper maintenance. SpaceX have stayed with a more traditional route, using refined kerosene, but despite the differences in their approach to rocket engines, the goals and design philosophies of the two companies – low cost, reusable, autonomous – are essentially the same. This is the polar opposite to the choices made by NASA for the successor to the Space Shuttle program.
Named by a planning committee with no sense of what the word exciting means, the Boeing-manufactured Space Launch System (SLS, for short) is very much Apollo reborn. Taking elements of the Space Shuttle launch system, such as the main engines and booster rockets, NASA has designed what appears to be, at first sight, a carbon copy of the Saturn V rocket.
At the time of writing, NASA has yet to launch a full size SLS system, with the first test mission not planned for another 1 to 2 years. If the parameters of the design are fully realized, then the SLS will be of the contenders for the crown for the largest, most powerful rocket in operation, but it will have essentially the same lifting capabilities of the 50 year old machine that sent mankind to the Moon.
The non-reusable nature of SLS, associated high mission costs, and construction delays have all drawn significant criticism from current and former NASA administrators, though. Part of the source of these issues is due to the fact that NASA is publicly funded through taxes, allowing various politicians to press for the organization to utilize companies that employ people in the states they represent. Another factor involves going back to the Moon, but we’ll say more about that in a moment.
The Space Launch System isn’t the only player in the heavy lifting field of rockets; both SpaceX and Blue Origin have designs that, if fully realized, are either similar in physical size to SLS or exceed its lifting capabilities.
There are two main reasons for all these manufacturers pushing for massive rockets, capable of lifting almost 100,000 pounds (around 45 metric tons) into Low Earth Orbit. The first is simple: there isn’t anything out there since the Saturn V that can handle anything like these loads. The Space Shuttle was rated to 54,000 pounds (roughly 24 metric tons) and Lockheed Martin/Boeing’s Delta V Heavy can move only 8,000 pounds more. SpaceX’s Falcon Heavy rocket is theoretically capable of considerably more, but has yet to be tested with a payload greater than 14,000 pounds (6 metric tons).
But this still doesn’t answer the fundamental question of why we need a rocket capable of lifting a bigger payload. Why does NASA need SLS to have the capability of putting 230,000 pounds into orbit?
Aiming for the moon (again)
In 2005, the US Congress signed in an act that authorized NASA to commence the so-called Constellation program. It’s aim was to develop a replacement for the Space Shuttle such that the International Space Station development could be continued and provide a new platform for manned missions to the Moon again. The whole thing was promptly unsigned, just 5 years later, when the true size of the costs became apparent.
A return to the Moon has been a repeated point of hot debate, ever since Apollo 17 left the ‘beautiful desolation’ back in 1972. Scientists and former Apollo astronauts have continually expressed dismay over the lack of human space exploration beyond Low Earth Orbit; politicians and economists have always countered such complaints with the same response: we can’t afford it.
NASA didn’t take the closure of Constellation lightly. Many of its elements were almost immediately recycled into a new program (SLS), along with a rough idea for another space station; the latter wasn’t to be a replacement for ISS though. Initially called the Deep Space Habitat, it was conceived to be a gateway to lunar exploration and beyond, and designed to be kept in orbit around the Moon, not Earth.
By 2016, things had changed (again) – a new US president was in power, who was rather keen on space projects, and a certain Elon Musk announced that his company had plans to colonize Mars. As it turned out, neither were vacuous promises, as within a year, Space Policy Directive 1 was announced (with a rather grumpy looking Buzz Aldrin in tow) and Musk provided more details, including fundamental rocket designs and the plan for how to pay for it.
Earlier this year, NASA renamed their manned mission program Artemis and confirmed a date for the Moon.
The promotional video for the Artemis program is light on details — SLS we already know about is in construction, but a full test flight has yet to take place; a test Orion capsule has been built, launched into space on top of a Delta VI rocket, and it returned safely to Earth.
However, Gateway (essentially Deep Space Habitat rebranded) has barely started, does not have the design, nor has a manufacturer for the lunar lander been decided upon. The technology required to do this already exists, but politics and money are influencing its rate of progress. Thus there’s a healthy dose of skepticism over NASA even getting to the Moon, let alone landing on it again, by 2024.
However, if we go back to 1964, five years before Neil and Buzz set foot on the Moon, the race to the Moon was in a similar state. The Apollo program had already begun, but no Saturn V rocket was ready and NASA was still battling with orbital rendezvous problems in the Gemini program. It would be another 4 years before humans were put in orbit around the Moon, in the Apollo 8 mission.
While NASA no longer enjoys the funding and manpower it experienced five decades ago, there are far more companies available to take design and manufacturing contracts — a total of eleven have so far been registered to develop lunar landing systems (complete and partial components) for consideration.
Blue Origin has already designed a lunar lander that has greater capabilities that the original LEM and plan to use variants of it in missions other than just Artemis. SpaceX is one of those eleven companies, but they also plan to send a tourist around the Moon, as part of an art project called #dearMoon.
And there’s another reason why a lunar landing may just take place in 2024: there’s a bigger prize at stake.
Going all out for Mars
As mentioned earlier in this article, Elon Musk is dead set on going to Mars (he’s even been clear on what he means by ‘dead’, too) and to do this, SpaceX is in the process of developing two new machines: a reusable launch rocket called Super Heavy (previous called Big Falcon Rocket) and a Shuttle-esque spacecraft called Starship.
Together they look like something straight out of a sci-fi movie and while the final product might not be quite so pristine and shiny, the Californian company is fully committed to the project.
You might wonder why a vessel designed for spaceflight has wings, albeit rather small ones, but they’re not for flying about on Mars — they’re for aerobraking on entry. Starship will actually land vertically, whether on Earth or Mars, using systems similar to those found in the Falcon series of rockets.
SpaceX has set no firm dates for reaching Mars and other than agreements with investors, they’re under no political pressure to achieve such a goal within a given time frame. For NASA, it’s a little different. They are using the Artemis program to develop systems and structures that can be put into place, before any attempt can be made at sending humans to the distant, little planet.
However, the Moon program is clearly being sold as a precursor to Mars and the latter is even being used to forge commercial partnerships and strengthen political alliances.
Although administrations come and go, NASA will be under pressure to deliver Artemis on time and make good progress in all the various programs that need to be conducted in order to carry a manned mission to Mars.
But if Artemis is a success, and we do see humans walking on the surface of the Moon again by the end of the next decade, then is a trip to Mars is guaranteed?
The chasm to leap
Sending humans to Mars and bringing them back home is a task that makes going to the Moon look like an afternoon jaunt to the beach. The first hurdle is a simple one: distance. At their closest, Earth and Mars are roughly 35 million miles (56 million km) apart, which is about 150 times greater than the average gap between Earth and the Moon.
For the Apollo missions, the journey between the rocky bodies took around 4 days; assuming the speeds are the same, going to Mars would take 600 days or 1.5 years.
The longest amount of time any human has spent in space is 438 days, by Valeri Polyakov on board the Russian Mir space station. The long term effects of living in micro gravity environments have been studied in depth over the years, and despite measures to combat loss of bone density, changes to gene and cognitive behavior, there is no escaping the fact that humans spending over a year in space travelling to Mars, will not be in an ideal state to conduct missions on the surface of the planet.
It takes months of rehabilitation to adjust on Earth after a typical six-month space mission
It’s worth bearing in mind that the 600 day journey in space would need to be done twice (there and back), and during this time, the planets continue to move, so Mars and Earth are at their closest every two years.
So the actual distance to cover will be more than 35 million miles and the crew will need to spend a few months on Mars, to provide time for the planets to realign back to a minimum separation. The longest period of time spent on the Moon was 3 days, by Eugene Cernan and Harrison Schmitt in the Apollo 17 mission.
One obvious solution to this is to increase the speed of the craft taking the crew to Mars. Apollo 10 currently holds the record for the fastest manned vehicle, peaking at just under 24,800 mph (39,900 km/h), and at that speed, the trip to Mars would only take a couple of months. However, the gravitational pull of the Earth was responsible for this, and trips to Mars aren’t going to be able to utilize this free ride.
The next big challenge is related to the first one, in that any humans on Mars will have to solve pretty much every serious problem by themselves. The quickest any radio signal can reach the little planet is just over 3 minutes (during minimum separation) but can take up to 22 minutes, and that’s just one way.
So there’s no chance of just ‘Googling’ a solution or conversing with mission control in real-time, unlike with the Apollo missions where contact with an engineer on Earth was never more than a couple of seconds. That means every engineering and medical issue that arises will require a suitable expert to hand, but what happens if that expert falls ill or is incapacitated in some way?
To address this will almost certainly require the crew to be knowledgeable and talented into multiple areas, backed up with digital guides and documents. The men that flew in the Apollo missions were trained in as many areas as possible, but they also had the advantage that NASA was just a second or two away.
Where and what else is possible?
Mars and the Moon aren’t the only goals in this new space race. Good old fashion tourism is right in the mix, even though it has been possible to ‘just’ buy a ticket for a journey to space for some time now.
In April 2001, Dennis Tito became the first space tourist in history, spending a week on the International Space Station, having paid the Russian Federal Space Agency an undisclosed sum of money for the training, place on the Soyuz rocket, and time on the ISS. While the figure paid is unknown, one reported estimate put it at $20 million.
That’s clearly way beyond the means of almost everyone, even those who would be deemed to be ‘well off’ by global standards. But it hasn’t stopped a number of companies setting forth to conquer such high risk ventures, with the most notable being Richard Branson’s Virgin Galactic.
Despite the name, the intended journey is only a brief flirtation with the edge of space. The spacecraft, bristling with composite materials and powered by a liquid fuel rocket, gets dropped from a bespoke heavy-lifting airplane at an altitude of 50,000 feet (15 km) and then powers on up to the Kármán line at 62 miles (100 km).
There, the crew and passengers experience a number of minutes of micro-g (i.e. floating around), before gliding back to Earth.
The project was unveiled in 2009, with initial ticket prices set at $200,000; around 300 people had apparently booked a place, even though they were told that it would 3 years until everything was ready.
It never was and the venture has yet to achieve its goals, especially due to the setback in 2014 when a test flight went seriously wrong (resulting in the death of one crew member, and heavily injuring the other).
SpaceX and Blue Origin are also interested in taking people for a blast into space, with the latter taking orders for flights on its New Shephard rocket for a quick blast to the Kármán line.
The above image shows how SpaceX envisions how the interior of the crew capsule of their Dragon craft might look like — the clinical nature and near total lack of instrumentation reflects the nature of how the craft functions and the nature of the crew, i.e. they’re not required to fly it nor have any control over it. The same is true for Blue Origin’s capsule (below):
A careful look at both images will show you how the choice of materials has changed since the days of Apollo. Cold metal panels, all painted military grey, are out; composite polymers and carbon fiber are in. The manufacturing costs of these have fallen dramatically in past decade or so, permitting a far more liberal use of them.
The benefit of this is, of course, weight saving and for every pound shaved off the spacecraft and launcher, the less fuel is needs to get into space and the cheaper and faster the whole flight becomes. One exception to this is SpaceX’s Starship, which is expected to be constructed mostly out of steel alloys, despite the significant weight problem.
The reason given for this is that Starship is a much larger cargo/passenger craft than Dragon and at its size, the use of carbon fiber composites for the entire craft would be an unacceptable increase in cost to the program.
Space tourism is very much on the cusp of becoming affordable, although this term really only applies to millionaires. But there’s money to be made elsewhere in space, in this new race, and it can be found in the form of huge lumps of rock, metal, and ice orbiting the Sun — otherwise known as asteroids.
These are essentially leftovers from the early days of our solar system — scraps of matter that didn’t coalesce with the rest to form planets. They come in all kinds of shapes and sizes; a few are the size of a small planet (e.g. Ceres), but the majority are barely big enough to hold together under their own gravity.
One such example is a carbonaceous asteroid called 101955 Bennu. There’s nothing particularly special about it, when compared to the millions of other asteroids out there, but this one just happens to orbit the Sun reasonably close to Earth; it’s also around 1600 feet (488 m) in diameter, with an average density similar to that of water.
For those two reasons, NASA launched a space probe to it, 3 years ago, named OSIRIS-REx. The mission goals were simple: get to the asteroid, put the probe in orbit around it, collect a sample of the asteroid itself, and return the material to Earth for analysis.
The asteroid’s proximity to us meant that it could be reached relatively quickly and it’s small size ensured that retrieving a sample wouldn’t require the use of a lander or drill. The collected pieces are scheduled for touchdown on Earth in December 2023, and scientists will be able to get a look at matter older than our planet.
So how exactly is this an opportunity for business? The OSIRIS-REx mission is one of the first steps needed for the mining of asteroids, many of which are known to be rich in metals, to become a commercial reality.
There are huge financial and technological hurdles to overcome; the first of which requires spaceflights to become far cheaper than they currently are, and this is where companies such as SpaceX and Blue Origin come in, with their reusable launch systems.
We’re certainly decades, maybe hundreds of years, away from seeing asteroids replacing the Earth as being the source for all rare metals and minerals, but don’t forget that the first powered flight by mankind took place at the start of the 20th century. It took less than 7 decades to go from Orville Wright’s 12 second flight into the history books to driving electric buggies and playing golf on the Moon.
What to make of this space race?
This new space race is nothing like the last one. There is no superpower cold war driving urgency and funds into it. Promises of returning to the Moon or sending humans to Mars aren’t new either, so these can’t be used as the reason for the race existing.
And yet, there is a race. It’s not a frantic sprint, though; this one is more akin to a marathon, and its competitors, bristling with ambition and no small amount of money behind them, are in for the whole distance. This is because there are clear financial incentives: rocket launches are becoming ever more cost effective and there are thousands of individuals and corporations willing to invest in space ventures.
There is an estimated 20 times more millionaires in the US alone, compared to the 1960s, and while this growth in individual wealth is partly due to the decrease in the value of the dollar, globalization and the spread of capitalism have also played their part. Where the notion of being a space tourist used to be nothing more than a flight of fancy, the chance of becoming a private astronaut is now very much a real thing.
The Apollo program helped generate so much new technology that we’re still feeling the benefits of it, 50 years later. So will this new space race do the same again; will computers and materials of the near future owe their existence to Musk, Bezos, et al? Probably not. Despite all the funds that SpaceX and Blue Origin have taken in, they’re still bound by the same limits. Space flight and human exploration of other worlds has to be affordable; resources can’t be wasted. Apollo had no such constraints in its heyday and flew on a Saturn V of progress and development, the likes we’ll probably never see again.
This new race is under way, with the start line now just a memory. But the Moon is still waiting for new people to take their own small step and giant leap, and Mars must wait even longer. They will wait, just as they have always done, and one day — 5 or 50 years from now — a new generation will watch these landings, and dream of running in their race, too.
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