Exoplanet Encyclopedia
Comprehensive guide to worlds beyond our solar system
Hot Jupiters
Gas giants orbiting very close to their host stars with extremely high surface temperatures.
Key Characteristics
- •Mass: Similar to Jupiter or larger
- •Orbital Period: Less than 10 days
- •Temperature: 1000-3000K
- •Distance from Star: < 0.1 AU
Notable Examples
51 Pegasi bHD 209458 bWASP-12b
Super-Earths
Rocky planets larger than Earth but smaller than Neptune, potentially habitable.
Key Characteristics
- •Mass: 2-10 Earth masses
- •Radius: 1.25-2 Earth radii
- •Composition: Rocky or water-rich
- •Potential for life: High
Notable Examples
Kepler-452bProxima Centauri bLHS 1140 b
Neptune-like
Ice giants with thick atmospheres of hydrogen and helium, similar to Neptune.
Key Characteristics
- •Mass: 10-50 Earth masses
- •Radius: 2-6 Earth radii
- •Atmosphere: H2, He, CH4
- •Temperature: Varies widely
Notable Examples
HAT-P-11bKepler-101bGJ 436 b
Gas Giants
Massive planets composed primarily of hydrogen and helium, like Jupiter and Saturn.
Key Characteristics
- •Mass: > 50 Earth masses
- •Radius: > 6 Earth radii
- •Composition: H2 and He
- •Often have ring systems
Notable Examples
HD 106906 bBeta Pictoris b51 Eridani b
Understanding Exoplanet Classification
Exoplanets are classified based on their mass, radius, composition, and orbital characteristics. The diversity of exoplanets discovered has challenged our understanding of planetary formation and revealed that our solar system is just one of many possible configurations.
5,000+
Confirmed Exoplanets
3,800+
Planetary Systems
800+
Multi-planet Systems