'Rebellious' exoplanet orbits opposite to its star's rotation

Astronomers have found an exoplanet that orbits its star in the opposite direction to the star's own rotation. Planets normally form from the same protoplanetary disk as their star and thus rotate the same way.

• The planet orbits its star in a retrograde direction
• Stars and their planets usually rotate the same way
• The backward orbit points to an unusual formation history