How did comets form? What are they made out of?

Astronomers are not certain how comets formed, but most believe that
comets formed at the same time our solar system did, perhaps even in
among the planets. Comets are made of a mixture of ices (water, methane,
carbon dioxide, etc) and dust. These are precisely the materials that
probably existed when the solar system was forming.

Sincerely,
Kurtis Williams

"A man is like a fraction whose numerator is what he is and
whose denominator is what he thinks of himself. The larger the
denominator the smaller the fraction. " -- Lev Tolstoy

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