Projections and feasibility of data centers in space
Earth has a limited amount of land, and data centers occupy large amounts of it. Data centers in space would reduce land use and energy costs, while improving processing speeds.
With rising demand for data storage, there is a need to build more data centers. To limit the amount of land these facilities would use, there are unique environments, such as space, that could house data centers.
Data centers in space may sound like a far-out, futuristic idea, but experimenting with existing computer technology in space could make this idea a reality in a matter of years. Data centers in low Earth orbit (LEO) could save land use on Earth, reduce energy costs due to solar power technology and reduce data latency.
Benefits to data centers in space
Data centers in LEO would provide lower energy costs, as well as technological and environmental benefits.
Lower energy costs with solar energy
On Earth, power and cooling are among the greatest costs associated with data center operations. In space, solar power and batteries would supply all the power, reducing the data center's running costs.
Additionally, a spacecraft -- in this case, a data center -- in LEO orbits the Earth roughly every 90 minutes. During that time, about 45 minutes are in sunlight, while the remaining time is in darkness. The energy reserve from the solar panels maintains the data center's batteries to keep the data center hardware running in the absence of sunlight.
Increased performance for satellite-based workloads
Placing a data center in orbit could improve performance for satellite-based workloads. Consider a satellite used for weather forecasting. This type of satellite must transmit raw data to Earth for processing. However, the day may come when weather satellites could instead transmit data to an orbital data center.
If the data center is close to the satellite, the satellite could transmit data to the data center at a higher rate of throughput than if the same satellite transmits data to a receiving station on the ground.
In orbit, raw data would be processed before being sent to Earth. This would improve the workload's overall performance, freeing up bandwidth at the receiving station.
Axiom Space has formed a partnership with Skyloom with the goal of creating the world's first orbital data center. Axiom Space plans to support data transmission speeds of 10 Gbps.
Data centers in LEO would save the limited land space left on Earth, leaving it for more efficient use, like farming or housing developments.
Environmental impact
One data center facility typically occupies about 40 acres of land on Earth, and hyperscale data centers occupy hundreds of acres. Data centers in LEO would save the limited land space left on Earth, leaving it for more efficient use, like farming or housing developments. These data centers would also use sustainable energy resources, like solar power and battery reserves, rather than the electric grid that ground data centers use.
Security
Data centers in LEO would have few physical security threats since it would be nearly impossible for someone to gain physical access to the data center. Orbital data centers would also be able to communicate with satellites and receiving stations using secure channels and closed communication systems, thereby helping to guard against cyberattacks.
Challenges with data centers in space
There are several different factors that can adversely affect computers in space, like extreme temperatures and the unpredictable environment.
Extreme force from launch
First, there is the launch that is necessary to reach space. Space vehicles endure extreme vibrations and high g-force loads during launch. These forces would likely damage or destroy any non-solid-state components, such as rotational hard drives.
Equipment destruction from radiation and cosmic rays
Radiation can cause bit flips and memory corruption. Similarly, galactic cosmic rays can cause high-energy particles to impact orbital systems. These particles can destroy or shorten the life of transistors. Error-correcting memory can help guard against memory corruption, but shielding against radioactive particles is also required.
Cooling systems
In space, there can be several hundred degrees of difference in temperature between sunlight and shadows. Conventional cooling systems are not as effective in space since convection does not work in microgravity. However, space-based computers, like those on the International Space Station (ISS), use radiators filled with ammonia for cooling.
Space threats and proper building materials
An orbital data center's infrastructure must protect the inside hardware from micrometeorite impacts and temperature fluctuations. The data center's engineers would make high-stress structural components primarily from stainless steel or titanium, while using aluminum alloy for most of the construction.
The data center would also require a layer of gold or silver foil to protect it against certain types of radiation and help with temperature control. A layer of Kevlar and Nextel could provide protection against impacts, while an external thermal blanket would provide additional insulation against extreme temperatures.
Could data centers function in space?
Given that the space environment is so hostile to computing hardware, it's worth questioning whether data center hardware could function in space. Recent experiments by HPE tested the durability and performance of computer hardware in launch and in orbit.
In 2017, HPE launched a supercomputer to the ISS to find out whether standard computing hardware could function in space without modifications. The two servers spent over a year and a half in orbit. While the system did manage to remain online and did not suffer any data loss, nine out of 20 solid-state drives failed during the mission.
Ultimately, the experiment demonstrated that off-the-shelf data center hardware could reliably function in space. However, HPE used special software for its Spaceborne Computer to keep the systems running smoothly. This software detects and corrects any errors introduced by radiation or galactic cosmic rays. HPE launched follow-up missions, sending additional data center hardware to the ISS in 2021 and 2024.
Considerations for space-based data centers
Measures exist for computers to properly function in space. As an example, space shuttles, like Challenger, Discovery and Endeavour, contained five general-purpose computers (GPCs). There were concerns about how the space environment might impact a computer's reliability.
The space shuttles' GPCs functioned similarly to a modern failover clustering environment in that, during normal operations, four computers were online at the same time. Each of these computers had a vote. If one of the computers made a mistake, the other GPCs overrode it. The fifth GPC served as a backup flight system that only functioned if one of the primary computers failed.
There are numerous challenges to consider and overcome for a computer to work in space, which is why the shuttles' GPCs had this configuration. Like the space shuttles, it will take trial and error to successfully deploy a permanent orbital data center, which would likely be unmanned. But, with persistence, the possibility of launching data centers in LEO may not be too far away.
Brien Posey is a former 22-time Microsoft MVP and a commercial astronaut candidate. In his more than 30 years in IT, he has served as a lead network engineer for the U.S. Department of Defense and a network administrator for some of the largest insurance companies in America.
