Hot Jupiter

Definition

A hot Jupiter is a gas giant exoplanet that orbits very close to its parent star, resulting in extremely high surface temperatures. These planets are similar in size and composition to Jupiter but have much shorter orbital periods and closer proximities to their stars.

5 Must Know Facts For Your Next Test

1. Hot Jupiters typically have orbital periods of less than 10 days.
2. They are thought to form further out from their star and migrate inward over time.
3. Their close proximity to their stars results in tidal locking, where one side always faces the star.
4. The high temperatures can cause atmospheric evaporation and significant mass loss over time.
5. Hot Jupiters were among the first types of exoplanets discovered due to the large radial velocity signals they produce.

Review Questions

• What causes a hot Jupiter's high surface temperature?
• How does the orbital period of a hot Jupiter compare to that of a typical gas giant like Jupiter?
• What process is believed to be responsible for moving hot Jupiters close to their parent stars?

Related terms

Exoplanet: A planet that orbits a star outside our solar system.

Radial Velocity Method: A technique used to detect exoplanets by observing Doppler shifts in the spectrum of the planet's parent star.

Tidal Locking: The phenomenon where an astronomical body's rotational period matches its orbital period around another body, causing one side to always face the other.