Interworld Slingshot: Exploring a new way to find resources in space

Before people can mine resources on the moon, asteroids or Mars, they need to answer a few key questions: What is there? How much is there? And where can it be found? A team led by SETI Institute research scientist Pablo Sobron is looking into a new way to answer these questions without having to land, drill or bring samples back to Earth.

The project is testing whether Raman spectroscopy—a technique already used in planetary exploration at close range—could be used from orbit or during fast flybys to identify minerals, water and other materials. The idea, called Interworld Slingshot Resource Surveys, suggests using a small spacecraft with one remote-sensing tool to study several places, such as the moon, a near-Earth asteroid and Phobos, one of Mars’ moons.

“The thing most likely to stop space mining may be that we cannot afford to prove there is anything worth mining. Land in the wrong place and you can lose an entire exploration program or a company, and nobody has enough money to keep sending spacecraft and hoping for the best,” says Sobron.

“We are asking whether Raman can give us an affordable way to put an X on the map before anyone commits to landing. And if the physics works, this may become much more than a mining tool; it could give us a new way to explore places like Europa and Enceladus for science.”

The problem before the mining problem

On Earth, mining companies do not start digging just because a spot looks promising. They spend years exploring, sampling, drilling and analyzing possible deposits to see if a resource is well understood and valuable enough to make extraction worth the cost.

This process helps reduce uncertainty and builds confidence in the size, makeup and accessibility of a deposit. Once these factors are clear enough, a resource becomes a reserve, and it attracts investment.

Doing this kind of exploration beyond Earth is much harder. Getting and returning samples is difficult and costly, and using robots to drill and analyze materials on another planet makes missions more complex. Current orbital methods also have limits. Looking at reflected light gives detailed images but does not always provide the specific or accurate measurements the team needs. Neutron and gamma-ray measurements can detect hydrogen, a key resource, but at a much lower spatial resolution.

Taking Raman spectroscopy to extreme distances

The NASA Innovative Advanced Concepts (NIAC) study will explore whether Raman spectroscopy could offer a new solution. Raman spectroscopy uses laser light aimed at a target and measures small changes in the light that bounces back. These changes reveal details about the material’s molecular structure, which helps identify what it is made of.

Raman instruments are already used in space missions. NASA’s Perseverance rover has Raman tools in its SHERLOC and SuperCam instruments, and Japan’s Martian Moons eXploration mission will use a Raman instrument to study Phobos. These tools help scientists study materials and decide which samples to examine.

The main challenge for Interworld Slingshot Resource Surveys is the distance involved.

Raman scattering is very faint and hard to detect. The project team says that only about one photon in 10 trillion is Raman-scattered. Sobron’s earlier long-distance Raman tests reached about 120 meters (394 feet). This study is looking at whether useful measurements can be made from much farther away, around 30 to 50 kilometers (19 to 31 miles).

To make this work with a small spacecraft, several engineering challenges need to be solved. The Phase I study will look at photon budgets, spacecraft paths and propulsion systems, sensitive single-photon detectors, precise pointing systems and very small lasers to see if the idea is technically possible.

It will teach the team whether it can deliver enough photons onto a meter-sized—or roughly meter-sized—spot to generate a Raman effect, and whether it can collect enough Raman photons to measure composition.

Current plans suggest the mission could last five to eight years, depending on the path and targets chosen. The idea is to take measurements while orbiting the moon and during flybys of a near-Earth asteroid and Phobos.

Putting an ‘X’ on the map

The goal is not to create a final map that puts economic values on space resources. Not yet.

Instead, the team hopes to find out whether remote Raman measurements can spot promising exploration targets, essentially putting an “X” on the map to show future missions where to take a closer look.

Ideally, these measurements would answer three key questions about a resource: How much is there? What form does it take? And where is it located?

If this idea works, it could help in more ways than just mining. Knowing more about local resources could mean future missions carry less extra equipment and supplies, cutting costs and risks. On asteroids, better scouting could help avoid landing in places with few resources. On the moon or Mars, knowing exactly what materials are available and where they are could help mission planners lower the weight and cost of cargo sent from Earth.

The Phase I study will first check whether the idea is physically and technically possible. Then, it will see whether it can be done with current parts and technologies that might need more work, or whether completely new technologies in lasers, detectors or spacecraft systems are needed.

The project brings together experts from the SETI Institute, NASA’s Goddard Space Flight Center, NASA’s Ames Research Center and the company OffWorld. The team includes Jane Lee, Xiaoli Sun, Alan Cassell, Rachel Ticknor, Dylan Morrison, Sobron and Jim Keravala.

“This is exactly the team you want around an idea this wild. We have some of NASA’s best space-laser and mission-design people working on the physics, and a pioneering space company telling us what a future market would actually need. They all thought I was crazy when I first suggested it, but they had also watched me push Raman to record distances and places, so they jumped in. The most likely result is that parts of the concept don’t work. That’s fine, because if it does, it could create an entirely new industry. That is precisely the kind of risk NIAC, and nobody else, takes,” says Sobron.

This study is an early step in solving a problem that could become more important as governments and private companies plan long-term work beyond Earth. It is not just about how to extract resources in space, but also about how to gather enough information to decide where it makes sense to try.

Who’s behind this story?

Robert Egan

Bachelor’s in mathematical biology, Master’s in creative writing. Well-traveled with unique perspectives on science and language.

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Andrew Zinin

Master’s in physics with research experience. Long-time science news enthusiast. Plays key role in Science X’s editorial success.

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