A new study is challenging the long-standing notion that the whole solar system formed from the same raw materials.

Until now most scientists had believed that the inner solar system bodies—Mercury, Venus, Earth, its moon, and Mars—had the same composition as primitive meteorites called chondrites.

But, problematically, Earth’s chemistry doesn’t quite match.

Now, French researcher Guillaume Caro, from Centre de Recherches Pétrographiques et Géochimiques in France, and his colleagues say that the makeup of Mars and the moon don’t correspond either.

It turns out the three bodies may be more similar to each other than the chondrite-rich asteroids located between Mars and Jupiter.

Full Story: National Geographic