The exoplanet 55 Cancri e is known as a planet that is approximately twice the size of Earth.
Discovering 55 Cancri e: A Super-Earth
55 Cancri e is a fascinating exoplanet located in the constellation Cancer, orbiting its star 55 Cancri A. It belongs to a class of planets often referred to as "super-Earths" because they are more massive than Earth but less massive than the ice giants like Neptune or Uranus. What makes 55 Cancri e particularly notable is its rocky composition and its significant size, being about twice Earth's diameter or radius.
Recent studies have revealed that this scorching, rocky planet possesses a thick atmosphere, a rare find among rocky exoplanets outside our solar system. This atmosphere is wrapped in a blanket primarily composed of carbon dioxide and carbon monoxide, indicating complex geological or atmospheric processes.
Key Characteristics of 55 Cancri e
- Classification: Super-Earth
- Size: Approximately twice the diameter of Earth.
- Composition: Predominantly rocky.
- Atmosphere: Known to have a significant and thick atmosphere, containing carbon dioxide and carbon monoxide.
- Orbital Period: Extremely short, completing an orbit around its star in less than 18 hours. This close proximity to its star results in incredibly high surface temperatures.
- Star System: Part of a binary star system, orbiting the star 55 Cancri A.
Comparative Overview: Earth vs. 55 Cancri e
To better understand the scale of 55 Cancri e relative to our home planet, here's a brief comparison:
| Feature | Earth | 55 Cancri e |
|---|---|---|
| Type | Terrestrial Planet | Super-Earth (Terrestrial/Rocky) |
| Size | ~12,742 km (diameter) | Approximately twice Earth's diameter |
| Mass | 1 Earth mass (5.972 × 10^24 kg) | Roughly 8.6 Earth masses |
| Atmosphere | Nitrogen, Oxygen, Argon, Carbon Dioxide | Primarily Carbon Dioxide, Carbon Monoxide |
| Temperature | ~15°C (average surface) | Extremely hot (thousands of degrees Celsius) |
| Orbit | ~365 days around the Sun | <18 hours around 55 Cancri A |
| Location | Solar System | 55 Cancri System (outside Solar System) |
While 55 Cancri e shares the characteristic of being a rocky planet with a substantial atmosphere, its extreme temperatures and unique atmospheric composition make it vastly different from Earth, offering valuable insights into the diversity of planetary environments in the universe.
