Here's why:
* Composition: Both moons are relatively small and have a composition similar to carbonaceous chondrite asteroids.
* Orbits: Their orbits are irregular and inclined compared to Mars's equator, which is unusual for moons formed alongside a planet.
* Origin: The leading theory suggests they were originally independent asteroids that were captured by Mars's gravity.
However, there are other theories about their origin, including:
* Mars's rings: They might have formed from a ring system around Mars, similar to Saturn's rings.
* Collision fragments: They could be debris from a larger body that collided with Mars in the early solar system.
While the captured asteroid theory is the most accepted, ongoing research and future missions could provide more definitive answers about the origin of Mars's moons.
