What is the orbital carrying capacity of near-Earth space? How much of it is occupied by defunct stuff? Who are the liable parties? How can I make people care about the near-Earth space environment? Those questions consume astrodynamicist and space environmentalist Moriba Jah.

Hundreds of thousands of satellites are planned for launch in the next few years to provide internet service to remote areas, facilitate navigation, synchronize time for banking, monitor climate change, and more. But so far the owner-operators function without globally agreed upon rules, and near-Earth orbit is getting crowded. The plethora of objects risk collisions, brighten the sky, and interfere with astronomy and casual sky gazing. (See Physics Today, April 2022, page 25.)

As an undergraduate at Embry-Riddle Aeronautical University in Arizona in the 1990s, Jah told himself he would never work on ‘something as unattractive as space garbage.’ Today he is a leader in the field. His goals start with cataloging and curating objects in near-Earth space. ‘If I can aggregate massive quantities of disparate, heterogeneous sources of information and bring those together to get insights, then we can have a conversation’ about shared use and stewardship of the space environment, he says.

Jah earned his PhD in 2005 at the University of Colorado Boulder for his estimates of spacecraft autonomously using atmospheric drag, or aero-braking, in the Mars atmosphere. After several years navigating interplanetary spacecraft at the Jet Propulsion Laboratory (JPL), Jah turned his attention to space junk. (See the article by David Wright, Physics Today, October 2007, page 35.) He is now a professor of aerospace engineering and engineering mechanics at the University of Texas at Austin.

PT- Could you start by describing your early years?

JAH- My father is from Sierra Leone and my mother is from Haiti. My father had visitation rights after they divorced. We lived in Monterey, California. When I was six or seven he kidnapped me. After nine days they found us someplace in the Bay Area. My mom didn’t want him to ever be able to find me again. My grandfather had a cousin who lived in Caracas—that’s what took us to Venezuela.

For high school I went to a military boarding school in Venezuela. My favorite subjects were biology and physics. The wicked problem facing society at the time was AIDS; people were dying right and left. As a teenager, I wanted to become a geneticist to solve AIDS. Physics allowed me to take my training wheels off—I realized I didn’t need someone else to tell me what the outcome of an event would be. If I threw a rock, I could figure out on my own what would happen. That was the first time I felt freedom in understanding the world around me.

My experience in military school set me up for wanting to continue in the military. When I graduated, I came back to the US and enlisted in the US Air Force. I guarded nukes in Montana.

I felt like my brain cells were wasting away, chasing ground squirrels off nuclear missile silos. But on my first night shift, I was wowed by the skies. The universe is peppered with stars. It made me feel connected to people who had come centuries before me and looked at the sky. I noticed some dots of light that moved across the sky and then disappeared, and I didn’t understand what could generate that motion if it wasn’t a UFO. It piqued my curiosity, and I found out they were human-made objects orbiting Earth and reflecting sunlight. When they disappeared, it was because they went into Earth’s shadow.

PT- How did you go from the military to becoming an engineer?

JAH- When I was curious about satellites, my enlisted friend Donald Wallace suggested that I study aerospace engineering. I didn’t even know what an engineer was until I was one. I was really into the science of motion in space, astrodynamics.

As an undergraduate, I went to an open house at JPL. There, I found some astrodynamicists and asked them where they had gone to school. The majority said one of three schools- the University of Colorado Boulder, the University of Texas at Austin, or Purdue University. UT never even replied to my application, but at the University of Colorado the late George Born took me under his wing.

PT- What did you do next?

JAH- After my PhD I worked as a spacecraft navigator at JPL. A few years in, I went to a conference on astrodynamics in Maui. My spouse and son came, and they fell in love with the island. They said, ‘Your days at JPL are done. You need to find a job on Maui.’ Within two years I moved my family there. I worked for the Air Force Research Lab. They have telescopes on top of Mount Haleakalā. That’s where I became acquainted with space traffic and the space debris problem.

PT- Is the air force interested in space debris and space traffic from the point of view of security?

JAH- Absolutely. I was there four years, and then the Air Force Research Lab relocated me to Kirtland Air Force Base in Albuquerque, New Mexico, where I spent another six years.

PT- What took you to UT Austin?

JAH- I felt too limited and constrained within the Department of Defense to do the things I wanted to achieve. So I looked for an academic job.

PT- What do you want to achieve?

JAH- I want to make everything in space known. I want to make space transparent and predictable. And I want to develop a body of evidence to hold people accountable for their behaviors in space.

PT- What kinds of things should people be accountable for?

JAH- People blow up their own satellites, creating a bunch of space garbage that then becomes a threat to satellites and human lives on the space station. Something just a centimeter in size can destroy another object if it’s moving kilometers per second.

PT- What is known about the stuff in near-Earth orbit?

JAH- Based on NASA and ESA [European Space Agency] data, there are an estimated 1-million-plus pieces of space debris ranging in size from a speck of paint to a school bus. About 27 000 human-made objects are being tracked in near-Earth orbit. Of those, only about 4000 work. The rest is garbage. Things are trackable down to about the size of a cell phone.

Through the company I cofounded last year, Privateer Space Inc, I am trying to transfer my academic research to create something like Waze [Waze Navigation and Live Traffic] for space—an app where anybody can contribute and the global community can take advantage of the information that others provide. The aims are to keep people safer and increase space security. Space environmentalism is my foundation. I want to protect near-Earth as a finite resource.

People are joy-sticking satellites—operators move satellites to avoid collisions, stay on intended orbits, move to other orbits, et cetera. It’s not just the physics of how these things behave in orbital space. There is a social scientific aspect, a cultural signature to the behavior of some subset of these objects, and we have not been able to quantify that yet. But the data display patterns and have structure. The patterns and structure allow us to form hypotheses and develop models, from which we can then make predictions.

PT- What’s the status of your Waze for space?

JAH- It’s still in its infancy. I created a knowledge graph database, AstriaGraph, which has been commercialized to Privateer. With AstriaGraph you can compare what different countries report—how many functioning and dead satellites there are in different orbits, how much debris. We are trying to come up with unique identities so we can do a better job of combining the information and delivering a standard to people. We still haven’t cracked the nut on this. We are trying to do the hard and soft science to figure out these things.

My general philosophy is that you can’t enforce things you can’t manage, you can’t manage things that you don’t know, and you can’t know things that you don’t measure. So measurements are the key.

PT- Do you have buy-in from space users?

JAH- I think everybody thinks it’s a great idea, but not many people are interested in funding it. So far, work has been funded largely by the Defense Department. With Privateer, we have nongovernment investors.

PT- What are your goals with Privateer?

JAH- It’s a private company that will provide services related to space traffic. Some services will be for a fee, and some will be free and accessible to anybody.

Services will include collision risk stuff. Other services might be monitoring space actor behavior for compliance or lack thereof with different laws. A company or country may ask for help figuring out what orbit to launch into—where it’s not overcrowded. Or someone in the space debris removal business might come to us and say their technology works on things that are a certain size or rotating quickly, or whatever, and ask for help locating such objects. Right now there is no place to look that up.

PT- What are the most urgent issues regarding space junk? And to what degree is it being cleaned up?

JAH- It’s not being cleaned up. There is no money behind it. But there can’t be money behind it unless you can quantify the impact of removing any given object, and you can’t have that unless you develop sustainability metrics, like a space traffic footprint that has a carbon footprint analog and orbital carrying capacity. Then you could say, Hey, I will pay you this much to remove that object. And if you do that, it removes this much of the space traffic footprint and provides this much capacity back to that orbital highway.

PT- How do you get to sustainable space?

JAH- Innovation and technology are not the long poles in the tent, in terms of solving the problems of space overuse. Compassion and empathy are required. I am on the hunt for being able to use empathy as a way to talk about space environmentalism.

PT- Describe your Shiftedspace.org project.

JAH- The idea is for me to be like a Tony Bourdain of space—I go around the world interviewing people. If you have the headsets, you can come along with me on a virtual reality journey and maybe experience an inner shifted space as a consequence. I hope to tell the story in such a way that it’s not only compelling, but motivates people to project themselves into different perspectives. For now, I’ve made a five-minute teaser with some kids on the island of Molokai in Hawaii. I am pitching the idea and trying to raise money.

I am trying storytelling, using immersive experiences and that sort of stuff, to see if I can elicit empathy. If we all know that we depend on each other and recognize that our lives depend on harmonizing among us, then we will treat each other a little better.

PT- How did you come to space environmentalism?

JAH- All of outer space might be infinite, but near-Earth orbit is not. People are launching lots of satellites into specific orbital highways. Those are becoming congested with time. People are making decisions in the absence of coordination and planning. For me, it’s a recipe for a tragedy of the commons, and that is what I am trying to prevent. Just like we have environmental protections for land, ocean, and air, we should have protections for near-Earth space.

I lived on Maui. I saw the displacement of native Hawaiians from colonization. I saw how they see themselves as stewards of the environment. The use of single-use plastics, landfills, and so on was juxtaposed for me with the space traffic problem, where I saw similarities in the lack of ecological sustainability.

Then, on a trip to Alaska in 2015 I had an inner spiritual moment. I woke up one morning and felt a presence that enveloped me. I felt a lot of compassion, and in my mind’s eye I saw humanity flashing throughout history, and how the intergenerational contract of stewardship has been abandoned. There are still remnants of stewardship in pockets of people across humanity, mostly among Indigenous cultures. I asked myself, Would I be willing to do everything I could to prevent humanity from completely forgetting and abandoning the idea of stewardship and interconnectedness? My answer was yes. That’s when I became a space environmentalist.