Picture two tissue box-sized spacecraft orbiting Earth.

Then picture them communicating, and using a water-powered thruster to approach each other. If you can do that, then you're up to speed on one of the activities of NASA's Small Spacecraft Technology Program (SSTP.)

It's all part of NASA's effort to develop small spacecraft to serve their space exploration, science, space operations, and aeronautics endeavors.

The two spacecraft are CubeSats, defined as no larger than 10 cm x 10 cm x 10 cm. They were in orbit around Earth, about 9 km (5.8 miles) from one another.

They established a radio communication link, then one of them issued a command to the other. The boss told the subordinate to fire its water-powered thruster and approach. (The water is turned to steam then used to propel the spacecraft.)

This little bit of drama is all part of developing small spacecraft that can do things autonomously. Rather than have people on the ground give each command to the CubeSats, they need only initiate the sequence, and the spacecraft do the rest.

"Demonstrations such as this will help advance technologies that will allow for greater and more extended use of small spacecraft in and beyond Earth-orbit," said Roger Hunter, program manager of the Small Spacecraft Technology program, in a brief press release.

This experiment was designed with safeguards in place. There were strict limitations on the types of instructions that the one spacecraft could issue to another.

The point of the experiment was to show that a human operator could initiate a sequence, then the spacecraft would take care of the specifics. The "boss" spacecraft could only issue authorized and pre-planned instructions.

"The OCSD team is very pleased to continue demonstrating new technical capabilities as part of this extended mission, over 1.5 years after deployment," said Darren Rowen, director of the Small Satellite Department at The Aerospace Corporation.

"It is exciting to think about the possibilities enabled with respect to deep space, autonomously organizing swarms of small spacecraft."

It seems clear that future exploration of space and planetary bodies will be enriched with more autonomous vehicles. Right now, NASA's MSL Curiosityis the premier space exploration vehicle.

But it operates with exquisitely detailed instructions sent from Earth. It's a model that's served our exploration needs well.

But in the future, things will change. A platform like the MSL may be more of a mother ship for exploration. Imagine a swarm of drones that call a stationary science platform home base. They are given an over-arching set of instructions on what to explore, and they go about organizing themselves according to pre-authorized instructions and algorithms that help them achieve their goals.

I think we all know that that's where we're heading, with AI being such a focus of development.

That's the vision, but this mission is all about baby steps.

This missions is part of NASA's Optical Communications and Sensor Demonstration (OCSD) mission. It's the type of bedrock work that has to be done before our visionary, AI-swarm exploration fantasies can be brought to fruition.

It's the second step in a meticulously-designed series of missions. The first OCSD mission launched in 2015. It was a risk-reduction mission designed to calibrate and fine-tune these two spacecraft, the OCSD-B and OCSD-C spacecraft.

All are part of NASA's Small Spacecraft Technology program within the agency's Space Technology Mission Directorate. The SSTP is managed from NASA's Ames Research Center in the Silicon Valley, California.

Because we're fed a constant diet of futuristic, science fiction movies and ideas, this instance of two spacecraft issuing instructions autonomously and then firing thrusters to close the distance might seem almost quaint. But it's not.

This is the type of detailed, step-by-step development work that has to be done if our future space-exploration aspirations are going to work out.

And it's all happening in orbit, right now.

This article was originally published by Universe Today. Read the original article.