Scientists have always believed that under the surface all the planets look about the same. But new data refute this thought.
The earth mantle consists of olivine, and everyone thinks that this is repeated on other planets. But open moon rocks show orthopyroxene. Approximately 4 billion years ago, a large-scale asteroid crashed into the moon, creating the largest Aitken basin at the south pole. The blow opened the mantle and the material came to the surface.
Researchers used remote sensing to analyze the observed outburst. The method uses the contact of sunlight with matter. It turned out that at this place there is a huge amount of orthopyroxene. Olivine is also there, but it is not the dominant element. The upper mantle is mostly green (olivine) with dark spots (orthopyroxene). But it is believed that under the surface their relationship is the opposite. So, perhaps, we still do not know much about the interior of other planets.