Details: This poster shows a shooting comet in space, near
Planet Earth. A comet is an icy small Solar System body that,
when close enough to the Sun, displays a visible coma (a thin,
fuzzy, temporary atmosphere) and sometimes also a tail. These
phenomena are both due to the effects of solar radiation and the
solar wind upon the nucleus of the comet. Comet nuclei are
themselves loose collections of ice, dust, and small rocky
particles, ranging from a few hundred meters to tens of
kilometers across. Comets have been observed since ancient times
and have historically been considered bad omens.