MELBOURNE, Fla. — For those who live along Florida’s Space Coast, the sight of rockets taking flight is becoming a weekly treat for the eyes.

Space enthusiasts in Virginia and southern California are also getting increasing amounts of eye candy as more missions launch from NASA’s Wallops Flight Facility and Vandenberg Space Force Base respectively.

But as more and more rockets send satellites and other payloads into space, our planet is becoming increasingly cluttered with a growing graveyard of orbital debris or space junk. It’s something that Dr. Madhur Tiwari, an aerospace, physics and space sciences assistant professor at Florida Tech said is something that’s on the minds of a lot of folks these days.

“Space debris is pretty much the hot topic as of now and it’s a challenging problem because we have an increasing number of space debris, and increasing number of space launches and it’s just going to exponentially go up,” Tiwari said.

The “hot topic” of space junk is far more than just something to muse about. It’s a growing concern for agencies, like NASA, and for the U.S. Department of Defense, both of whom rely on assets in various orbits around Earth for research, observation and security.

The International Space Station also performs avoidance maneuvers every so often to dodge debris that could cross its path, something that goes back to the years before the first modules were launched. Tiwari said there currently are more than 20,000 pieces of space debris the size of a golf ball or larger.

“It’s an immense problem because a golf ball here on Earth which is not moving in respect to you doesn’t mean a thing, but imagine a golf ball going so fast, like a spacecraft, hundreds of thousands of miles an hour sometimes, hitting something like an ISS, for example, is a big problem,” he said.

Like many who went into space-related fields, Tiwari was inspired by sci-fi classics, like Star Trek and Star Wars. The self-professed Trekkie focuses his research these days is in guidance, navigation and control to create autonomous systems in space.

He said the research into the issue of space debris has been going for quite some time and in order for the low Earth orbit economy to really live long and prosper, it’s time to go from theory to practice.

“We have done the theoretical aspects of this work. We have been doing this for a really long time, even my students and the other academic community has been working on for decades, actually,” Tiwari said. “This is not that new in terms of research. It is new in terms of actually applying this stuff. So, I do believe it is about time that we address these concerns.”

Seeking solutions to avoid costly problems

Agencies and companies around the world are beginning to take the advice of Tiwari and others to make the concepts concrete.

In March, NASA published a report dubbed the “Cost and Benefit Analysis of Orbital Debris Remediation.” As its name suggests, it examined the broad costs of different methods of clearing out some of the junk from our orbital attic.

The two main scenarios looked at tackling the big stuff and the smaller pieces. For the large debris removal, NASA studied “removing the 50  statistically most-concerning derelict objects in (low Earth orbit),” which was found to have a $3.5 million benefit in risk reduction after the first year.

Small debris solutions meant evaluating “the benefits of removing 100,000 pieces of 1-10 cm debris from 450-850 km altitude,” would save about $23 million. The report noted that while the dollar amount is larger than the Top 50 approach, it also removes a larger quantity permanently.

For comparison, the ISS orbits the Earth at an altitude of about 402 km or 250 nautical miles. It’s altitude range is from 370-460 km, which is the upper certified limit for the Russian-provided Progress spacecraft that keep the Space Station in the correct orbit.

NASA’s report reached the following main conclusions:

1. The most effective remediation methods to reduce risks to operators are approaches for removing small debris and nudging large debris to avoid collisions.
2. Controlled and uncontrolled reentry via reusable remediation servicer may reach net benefits on timescales that are relevant to spacecraft operators.
3. Recycling space debris has some attractive features, but does not offer a clear risk advantage over other approaches.

Tiwari’s area of research focuses on autonomous systems in space. It led the Embry-Riddle Aeronautical University graduate to becoming the director of The Autonomy Lab at Florida Tech.

“This is a great avenue for us to test our algorithms, right, because we’re always looking for interesting problems where we can test how what we are doing can help,” Tiwari said. “This is why we’re in this. It’s because we feel that our algorithms, our technology can actually help push this further and contribute towards dealing with a lot of space problems and one of the space problems is dealing with space debris.”

One project he and his gradate and doctoral students are working on is a machine learning system that can identify a defunct satellite by its individual components, like solar panels. The system is ultimately designed to construct 3D models of space debris without needing to relay information back to a ground tracker.

“Once we have the 3D models, the main objective is to plan these missions to interact with another spacecraft. It doesn’t have to be another spacecraft. It can be space debris, it can be other parts of spacecraft, anything that we want to move away or maybe repair,” Tiwari said.

In partnership with private company, Creare, they received a $150,000 Small Business Technology Transfer (STTR) grant from the Small Business Association to train multiple swarm satellites (they use drone as a lab substitute) to figure out the best part of the target satellite for interaction.

“Our algorithm is very generalized, so we don’t need to know what this spacecraft looks like in order for us to perform operations around it,” said Trupti Mahendrakar, a Florida Tech PhD aerospace engineering student working in The Autonomy Lab. “Our algorithm has seen most spacecraft, except for the ones that we use in the lab. So, we are able to perform the swarm operations around an unknown target that we’ve never seen before.”

Mahendrakar said that training algorithms for the unknown is important, since some of the space debris they could encounter in the future may be stuff for which there aren’t good, existing 3D models upon which to train the system.

Last year, SpaceWERX, dubbed “the innovation arm of the U.S. Space Force,” awarded 124 Phase 1 contracts to 66 research institutions and 92 private companies as part of the Orbital Prime program. Each of the $250,000 grants was issued for a  five-month period for their work to “invigorate the In-space Servicing, Assembly and Manufacturing, or ISAM, market using Active Debris Remediation as a use case for the foundational technologies.”

SCOUT Space Inc. was one of the private company winners announced in Aug. 2022, which chose to partner with Florida Tech and the Stanford University Space Rendezvous Laboratory (SLAB). Tiwari said the focus of their work was on predicting uncertainty when it comes to one spacecraft identifying where another spacecraft is located relative to itself.

“If we can quantify this uncertainty, we can design our missions around that uncertainty,” Tiwari said. “That way, we have a more robust mission design and more robust autonomous systems, so that we can perform these missions.”

With a growing number of players in this arena, there will be more and more potential solutions for an increasing problem.

“I think the time is now. I do believe that we’re responding at close to the right time. These things do take time, especially space. It’s a lot of money, it’s a lot of regulations,” Tiwari said. “So, I do believe that all of these things combined, I would say that we are almost on time and I do believe that we are preparing for the future missions, definitely.”