Meteorites from Mars contain specks of graphite-like carbon
trapped within them. There have been a variety of explanations
for this reduced form of carbon over the years, with some even
viewing it as an indication of life on the Red Planet. But new
evidence indicates that the rock holding the carbon is volcanic
in origin and originated from deep inside the planet, not from
living organisms. This helps scientists narrow down possible
chemical reactions on the planet that could create building
blocks for life, the researchers say. Scientists have found
reduced carbon compounds, like polycyclic aromatic hydrocarbons,
in various meteorites with a Martian origin over the past 15
years. They’re particularly interested in this type of carbon—as
opposed to the oxidized carbon in carbon dioxide and carbonate
minerals—because it contains carbon-carbon bonds critical to
life as we know it. There are many different ways that these
compounds can form in space, so finding reduced carbon in the
meteorites tells scientists v