article_snippet: Cometary dust is composed of as much as 25 percent carbon by weight, so Mercury would be exposed to a steady bombardment of carbon from these crumbling comets.
article_snippet: Using a model of impact delivery and a known estimate of micrometeorite flux at Mercury, researchers calculated suggest that after billions of years of bombardment, Mercury's surface should be anywhere from 3 to 6 percent carbon. '
article_snippet: One thing that hadn't been considered was that Mercury gets dumped on by a lot of material derived from comets.'
article_snippet: But spectral data from Mercury suggests spectral data from Mercury surface contains very little nanophase iron, certainly not enough to account for spectral data from Mercury dim appearance.
article_snippet: As comets approach Mercury's neighborhood near the sun, the researchers often start to break apart.
article_snippet: Cometary dust is composed of as much as 25 percent carbon by weight, so Mercury would be exposed to a steady bombardment of carbon from these crumbling comets.
article_snippet: Using a model of impact delivery and a known estimate of micrometeorite flux at Mercury, Bruck Syal was able to estimate how often cometary material would impact Mercury, how much carbon would stick to Mercury's surface, and how much would be thrown back into space.
article_snippet: Bruck Syal calculations suggest that after billions of years of bombardment, Mercury's surface should be anywhere from 3 to 6 percent carbon.
article_snippet: Importantly, spectroscopic analysis of the impact samples revealed no distinctive spectral fingerprints, again similar to flat spectral signatures from Mercury. '
highlights_snippet: Mercury's surface is anywhere from 3 to 6 percent carbon .
  