The ability to make things in space will be crucial to enabling larger exploration, research and industry across the Solar System.
Although launch costs are coming down it takes a huge amount of energy, and indeed time, to transport objects into orbit.
There is also a wealth of materials, such as rare metals, present in bodies relatively close to Earth that can be extracted and used.
Manufacturing in space has some unique advantages; an abundance of solar energy, a lack of gravity, access to an infinite (and free) heat sink just outside the factory window, and the ability to use a manufacturing environment that is virtually 100% sterile.
In-space manufacturing technology obviously faces many challenges due to the environment, but there are many projects and businesses currently investigating exactly how to create different products off Earth. Here are a few notable examples:
Semiconductors
Semiconductors are essential for most electrical circuits and components.
The semi-conducting material gallium arsenide (GaAs) was one of the first materials made in space; at the Wake Shield Facility back in the 1990s.
GaAs can be used in diodes, field-effect transistors (FETs) and integrated circuits (ICs), generating very little noise and operating effectively at ultra-high radio frequencies.
Here on Earth (assuming that’s where you’re reading from…) creating thin film semiconductors such as GaAs can be challenging as the material is easily contaminated by particles in the air.
Manufacture semiconductors in the ultrapure vacuum of space and you don’t have this problem![1]
Protein crystals
In recent years a new class of drugs has been developed which compel the body’s immune system to target specific attacking cells and bacteria.
Called monoclonal antibodies (MABs) these drugs are engineered proteins that can be designed to target almost any attacking cell, such as cancer.
In order to be effective large quantities are needed – usually delivered intravenously over several hours.
However, if the proteins can be crystallised in space, the lack of gravity means that larger crystals can be developed a lot more efficiently.
And larger protein crystals enables MAB treatments with higher concentrations – so that long intravenous procedure can be replaced with a simple injection, delivering the same exact dose.[2]
Stations, infrastructure and other facilities
While many pieces of space hardware, such as Cubesats for example, are launched readymade, other structures need to be assembled in space.
The International Space Station (ISS) is a great example.
Weighing more than 400 tonnes and covering an area the size of a football pitch, the ISS is far too big and complex to have been put into orbit fully formed.
Instead, more than 40 separate missions involving space agencies across the globe has resulted in arguably the largest cooperative international science and technology project the world has ever seen.[3]
But the ISS could one day be dwarfed by other facilities and systems made in space.
Large-scale manufacturing and megastructures
A lack of gravity makes it easier to move around massive amounts of material.
Manufacturing processes that need expensive equipment and reinforced facilities on Earth could be carried out more safely and with far fewer resources in orbit.
But the development of larger structures in space won’t be done by astronauts – it will need technology that can safely move and arrange parts and materials (through some form of propulsion for example), and then assemble them once in place.
And Made in Space), a company very much at the forefront of in-space manufacturing, has recently tested a system it is developing with NASA that could soon provide just that.
The company’s Archinaut concept uses additive manufacturing (aka 3D printing) and robotic assembly capabilities to demonstrate how large structures can be built in space.
It has successfully printed and joined together several parts in an environment simulating the conditions of space and the next step is to test the technology in orbit.[4]
In addition, the ESA has also just launched a new tender on the in-orbit integration of GEO satellites and 3D printing, in orbit, of large satellite structures.
If interested, you can find more information on this tender here.
Perhaps projects like Archinaut could one day pave the way for the development of even more ambitious structures that have been discussed in science fiction. Here are a few examples you might have heard of:
- Space elevators – a giant cable anchored to Earth at one end and to a space-based facility at the other, enabling transportation into space.
- Dyson spheres and swarms – space-based solar energy collectors positioned around a star; consisting of multiple independent collectors in the case of a swarm, and a gigantic collector completely encapsulating the star in the case of a sphere.
- Orbital rings – an artificial ring surrounding the Earth (probably based at the equator) to enable faster planetary transport, easier access to space (by connecting to space elevators) and to act as a space station.
OK, we’re unlikely to be seeing any calls for proposals by NASA or the ESA to build these megastructures any time soon.
In-space manufacturing, like any other new industry sector, needs solid commercial opportunities on which innovation and investment will be based, such as the next few products.
Advanced fibre optics
The speed and capacity of communication and data exchange across the globe are important drivers in many industries.
Vast networks of metal wire and fibre optic cables criss-cross countries, connecting cities and powering markets, technology products, energy systems, media and more.
And the industry is always seeking greater efficiency and speed.
One promising material is an exotic optical fibre called ZBLAN (which stands for zirconium, barium, lanthanum, sodium and aluminium).
The manufacture of ZBLAN involves suspending the constituent parts from a height and using Earth’s gravity to begin elongating the material.
However, this process can result in tiny flaws along the length of the fibre resulting in the formation of crystals that can significantly reduce signal loss.
When developed in microgravity these flaws are minimised, and the performance of the resulting fibre can be orders of magnitude above that of fibre created on Earth.[5]
ZBLAN is both expensive and light enough to justify in-space manufacture from a commercial perspective.
Currently both Made In Space, in partnership with Thorlabs), and a San Diego based company called FOMS are pursuing fibre optic manufacturing in space.
Tools, replacements and recycling
Made In Space are also working with NASA and other partners on solutions for creating specialist tools and replacement parts in orbit.
Despite a decrease in launch costs astronauts still need to carry as little as possible and the ability to make certain items in space, as needed, is very useful.
At NASA’s Additive Manufacturing Facility (AMF) on the ISS they have worked with Made In Space and other partners to create an advanced 3D printing facility that works in microgravity.[6]
The AMF system can create items made from more than 20 different materials and, since it became operational in 2016, has created more than 100 tools and parts including:
- The first commercial part ever produced in space; a Kobalt wrench,
- The first medical supply item ever printed in orbit; a customized finger splint,
- The first piece of art ever 3D printed in space, and
- The first item printed in space from Polyetherimide/Polycarbonate (PEI/PC) – a strong, heat-resistant, aerospace-grade material.[7]
But sustainable 3D printing requires a supply of raw material (the ‘feedstock’) to manufacture with. And one of the best sources could be to recycle parts and components no longer needed on-board space stations or from other artificial objects in orbit.
A US-based company Tethers Unlimited has been working with NASA to develop and test it’s Refabricator technology.
The system combines integrated plastic recycling and 3D printing capabilities, enabling astronauts to reuse material already on the ISS to make new tools and structures.[8]
Being able to recycle material already in space will give some manufacturing processes a distinct advantage and enable the development of closed-loop facilities with more efficient and cost-effective capabilities.
Human organs
Modern biology has made great strides in the growth of human organs for patients with a wide range of ailments.
Traditional transplants can often only be temporary fixes, or might fail entirely endangering the patient further, but organs grown from cells extracted and cultured from an individual have a far higher chance of being accepted by the body.
However, on Earth gravity (again!) can make it harder for the organs to grow properly.
Tissues and cellular structures can collapse under their own weight and capillaries can fail to propagate blood and other liquids.
As you might have guessed, space might hold the answer.
A company called Techshot has developed a BioFabrication Facility (BFF) that uses 3D printing techniques to grow biological patches for heart repairs.
The system is due for launch to the ISS in May of 2019 and will test the concept of developing new organ material from a patient’s own cellular material.[9]
If the approach is successful, and can be effectively scaled up, one day it will be possible to send a patient’s cells to a space station, 3D print a new organ, and get it sent back to Earth to be implanted in the patient.
Rather than languishing on a donor waiting list for potentially years, a healthy organ almost guaranteed to be accepted by the body could be with a patient in a matter of months, or even weeks.
Food
Enjoying food in space is notoriously challenging for many astronauts.
Everything transported on missions or to space stations is preserved in a form that can affect the taste, diversity and texture of the food.
Now, US startup BeeHex has developed technology that might make this a thing of the past.
BeeHex’s Chef 3D system is designed to 3D print food items in space, enabling astronauts to enjoy their favourite foods freshly prepared (sort of!) for them in orbit.[10]
As various companies and agencies gear up for manned missions to Mars, solutions for creating different kinds of food in space could be very important.
In conclusion
Space as a factory environment presents a range of challenges and opportunities.
As innovative technologies come online, and the demand for newer capabilities in space grows, we expect this sector to expand significantly.
What in-space manufactured products are you most looking forward to?
Links and resources:
[1] Space Research Results Purify Semiconductor Materials
[2] Protein Crystals in Microgravity
[3] Building the International Space Station
[4] Made In Space successfully demonstrates Archinaut additive manufacturing and assembly capabilities
[5] Optical Fiber Manufacturing: Gravity-free optical fiber manufacturing breaks Earthly limitations
[6] Additive Manufacturing Facility
[7] Additive Manufacturing Facility: 3D Printing The Future in Space
[8] NASA’s ‘Refabricator’ lets astronauts recycle 3D-printed tools to make new ones
[9] Why your new heart could be made in space one day
[10] NASA Astronauts Can Now 3D-Print Pizzas in Space