NASA’s Space Communications and Navigation programme (SCaN) has demonstrated the first two way end-to-end laser relay system, deployed through an innovative network. To test SCaN, they sent data to the International Space Station at the impressive speed of 1.2 gigabits per second. Using bandwidth that would normally be reserved for more important communications, the chosen message for the test was a set of adorable images and videos featuring the pets of NASA astronauts and staffers.
A group of astronauts and employees from NASA, including Randy Bresnik, Cristina Kock and Kjell Lindgren chose NASA’s first two-way, end-to-end laser relay system test to send photos of their cherished pets to the International Space Station. As full colour images and videos, they are more complex, containing many more pixels than text or technical diagram transmissions. This made it the perfect dataset to demonstrate the speed and agility of the Integrated LCRD Low Earth Orbit User Modem and Amplifier Terminal (ILLUMA-T) system.
The demonstration also tested a new networking technique. Space data transmission faces significant delays and potential data loss due to the vast distances involved. To address this, NASA developed Delay/Disruption Tolerant Networking (DTN), which uses a “store-and-forward” process to handle data disruptions. An advanced implementation of DTN called High-Rate Delay Tolerant Networking (HDTN), developed by NASA’s Glenn Research Center, further enhances this by enabling data transfer up to four times faster than current DTN technology. HDTN aggregates data from various sources and prepares it for transmission back to Earth, demonstrating its capabilities during the pet photo and video experiment.
The data began its journey at a mission operations center in Las Cruces, New Mexico, before being routed to optical ground stations in California and Hawaii. From there, the data was modulated onto infrared laser signals and sent to NASA’s Laser Communications Relay Demonstration (LCRD) satellite in geosynchronous orbit, which then relayed the data to the ILLUMA-T on the space station.
Historically, NASA has relied on radio frequency communications for data transfer to and from on-board computers beyond our atmosphere. With the breakthrough of laser communications (better known as optical communications,) more complex messages and data packets can be transferred much more quickly. This is possible because although both radio waves and infrared light travel at the speed of light, infrared moves in a tighter wavelength. This allows the signal to be modulated much more rapidly, which means that more information can be sent in the same amount of time.
Laser communication also promises to improve the working and living environment in orbit. The ILLUMA-T laser communication terminal is smaller, lighter and requires less power than existing systems. With more space, and a reduced drain on power, the system will improve communication with earth and make life a little easier for astronauts on the space station.
The SCaN test highlighted the speed and efficacy of how powerful the laser communications system can be and also emphasised the value of multi-program demonstrations. According to deputy associate administrator and SCaN program manager at NASA, Kevin Coggins, the campaign has been successful for both the ILLUM-TLCRD and HDTN. “Not only have they demonstrated how these technologies can play an essential role in enabling NASA’s future science and exploration missions, it also provided a fun opportunity for the teams to “picture” their pets assisting with this innovative demonstration.”
Using pet footage as the test was inspired by the December 2023 NASA laser communication test that streamed a video of a ginger tabby called “Taters”, chasing the dot from a laser pointer. It was sent from the Psyche spacecraft almost 30 million kilometers away to the Hale Telescope at the Palomar observatory in California. The 15 second HD video took just 101 minutes to reach its destination and represents one of the first successful high-bandwidth laser communications transmission tests into deep space. As the deputy administrator at NASA said at the time, “Increasing our bandwidth is essential to achieving our future exploration and science goals, and we look forward to the continued advancement of this technology and the transformation of how we communicate during future interplanetary missions.” Although Taters does not hold the distinction of being the first cat in space (that was Félicette in 1963) he can proudly call himself the subject of the first cat video in space.
This optimized DTN technology aims to enhance NASA’s communications services, including improved security, network routing of high-definition multimedia, and more. As NASA’s Artemis program advances toward establishing a sustainable lunar presence, SCaN continues to develop innovative communications technology to bring the reliability and performance of Earth’s internet to space.
ILLUMA-T, LCRD, and HDTN are funded by NASA’s Space Communications and Navigation (SCaN) program at NASA Headquarters. LCRD and ILLUMA-T are managed by NASA’s Goddard Space Flight Center, while HDTN is managed by NASA’s Glenn Research Center. The space station network is managed by NASA’s Johnson Space Center and Marshall Space Flight Center.
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