On Dec. 11, NASA engineers anxiously gathered at the Jet Propulsion Laboratory in Pasadena, Calif., to view a cat video, wondering if it would be in the pristine high definition for which they had hoped.
To their relief, it was. For the first time, high-definition video — this one of a lab employee’s cat named Taters — was streamed from 18.6 million miles away, or roughly 80 times the distance from the Earth to the moon, the farthest ever.
The demonstration was part of NASA’s Deep Space Optical Communications experiment, aimed at improving the infrastructure for communication beyond the Earth’s orbit. As one example, if humans are to go to Mars, the need exists for larger amounts of data to be transmitted over a longer distance. This demonstration marked another step toward such a possibility.
“This would be like the same capability that you’d want to have if you’re sending an astronaut to the surface of Mars or something like that,” said Dr. Abhijit Biswas, the project technologist. “You want to have constant contact with them.”
The demonstration was done with the help of NASA’s Psyche spacecraft, which was launched on Oct. 13 with the aim of exploring an asteroid with the same name. The D.S.O.C. experiment is using laser communications, as opposed to traditional radio frequencies, in an attempt to transfer large gobs of data at faster rates over greater distances. (The video is of Taters chasing a laser pointer. In 1928, a statue of the cartoon character Felix the Cat was used to test television transmissions.)
The transmitted data rates of 267 megabits per second are comparable to rates on Earth, which are often between 100 and 300 megabits per second. But Dr. Biswas urged caution about the results of the demonstration.
“This is the first step,” he said. “There’s still significant requirements for ground infrastructure and things like that to take something that’s kind of a proof of concept to transform it into something that’s operational and reliable.”
The video was transmitted using a flight laser transceiver, one of several pieces of new hardware being deployed for the first time. The D.S.O.C. system is made up of three parts: the transceiver, which was installed on board the Psyche spacecraft, and two components on Earth: a ground laser transmitter (roughly a 90-minute drive from the laboratory) and a ground laser receiver at the Palomar Observatory in Southern California.
“It’s a little mind-blowing right there that you’re able to do all that in the end,” said Dr. Meera Srinivasan, the project’s operations lead.
Dr. Biswas and Dr. Srinivasan, along with other NASA engineers, have been working to develop this technology for decades. The focus was to scale up the optical communications technology that was already being used on satellites orbiting much closer to Earth. Initially, before the Psyche mission, the team hit roadblocks because the signal was too weak. So NASA developed technologies to extend the capabilities. Deep space, Dr. Biswas said, was “the new frontier.”
To begin the process for the cat video, the ground transmitter first sent up the laser beam. The aim had to be precise. Psyche then locked on to that signal and sent the content, which had been preloaded by the NASA team, back down to the receiver. For the transmission to work, it needed to be done during a cloud-free night, which would allow a proper line of sight.
“There’s many little steps,” Dr. Biswas said. “Each one has to fall in place at the right time. And that’s the terrifying part because we’re doing it for the first time. This hasn’t been done before. It’s not like, ‘Oh, we know if you do this, that’ll happen.’ We’re kind of working our way through all these things.”
He added: “And then once it all works, it seems like it’s so easy. Why were we worried in the first place?”
Now, the D.S.O.C. project is to test their limits. At the end of June, the NASA engineers expect to be able to transmit from a distance that is 10 times as far: 186 million miles.
