A distant planet has been found to orbit its star in the “wrong” direction, challenging traditional theories of planetary formation.
Virtually all planets orbit their star in the same direction as the star’s spin but WASP-17b orbits in the opposite direction.
Planets usually form from the same disc of rotating material that gave birth to the star around which they move, but WASP-17b’s retrograde motion is somewhat of a mystery to scientists.
Read more at Australian National University