What does observing a Hot Jupiter in a 'retrograde' or 'wrong-way' orbit imply about its past?
Answer
That the inward migration involved a major dynamical event, possibly flipping its angular momentum
A retrograde orbit, where the planet orbits opposite to the star's rotation, suggests a violent gravitational interaction flipped the planet's angular momentum.

#Videos
Hot Jupiter Study - YouTube
Related Questions
What characteristic primarily defines the location of a Hot Jupiter exoplanet?How do the orbital periods of Hot Jupiters generally compare to Mercury's 88-day revolution?What condition is a Hot Jupiter likely to experience due to its extreme gravitational proximity to its star?What temperature range might the daytime side of an 'ultra-hot Jupiter' exceed?What severe physical consequence results from the intense stellar radiation bombarding an extreme Hot Jupiter?According to current leading theories, where did Hot Jupiters originally form before migrating to their current positions?What mechanism is cited as a possible cause for the inward migration of a Hot Jupiter?What orbital feature in some Hot Jupiters suggests a history of violent formation or gravitational scattering?What does observing a Hot Jupiter in a 'retrograde' or 'wrong-way' orbit imply about its past?Why is the current location of a Hot Jupiter considered a transient state on a cosmic timescale?