Scientists say in a new study the discovery of ‘mini-moons’ caught in Earth’s orbit could offer a better understanding of what makes up asteroids.

Researchers say the mini-moons are small asteroids temporarily captured in Earth’s orbit. The objects are usually between 1-2 meters in size and have been difficult to detect because they move out of Earth’s orbit so quickly. To date, only one mini-moon has ever been discovered.

“These asteroids are delivered towards Earth from the main asteroid belt between Mars and Jupiter via gravitational interactions with the Sun and planets in our solar system,” said Dr. Robert Jedicke, lead author, based at the Institute of Astronomy at the University of Hawaii, in a statement. “The challenge lies in finding these small objects, despite their close proximity.”

Some mini-moons may fly past Earth, while others complete a revolution around the planet before either escaping its orbit or entering its atmosphere, scientists say.

The study was published in the journal Frontiers in Astronomy and Space Science.

Researchers say the creation of a new telescope — the Large Synoptic Survey Telescope (LSST) — will make it easier to capture these mini-moons as they move through Earth’s orbit.

The discovery of these objects will help experts get a better scientific understanding of the origins of asteroids.