What is the myth behind the constellation Virgo?

Virgo was Ceres, the mother (patroness) of crop fertility. She is usually pictured carrying a spike (a shief, a shock) of some cereal crop. Spica is the brightest star in that "spike."

Ceres, goddess of agriculture. When the Sun gets to that constellation, it is time to harvest the grains. It could also represent Astraea (daughter of Zeus), goddess of Justice -- the "scales of justice" Libra is the next constellation over (near her feet). I have read some interpretations where she represents Callisto, but Callisto is already in the sky as the Great Bear (she was changed into a bear by the very jealous Hera, then killed by a hunter -- Zeus took pity and placed her among the star with her child, the small bear). And there are many more minor myths.

Ceres, goddess of agriculture.

When the Sun gets to that constellation, it is time to harvest the grains.

It could also represent Astraea (daughter of Zeus), goddess of Justice -- the "scales of justice" Libra is the next constellation over (near her feet).

I have read some interpretations where she represents Callisto, but Callisto is already in the sky as the Great Bear (she was changed into a bear by the very jealous Hera, then killed by a hunter -- Zeus took pity and placed her among the star with her child, the small bear).

And there are many more minor myths.

its closer then you think