The darkest planet discovered to date is TrES-2b.
TrES-2b, an exoplanet orbiting the star GSC 03549-02811, is known for its extremely low albedo, making it darker than coal. This means it reflects very little light, absorbing almost all the light that reaches it. Here's a closer look:
Key Characteristics of TrES-2b:
- Extremely Low Albedo: TrES-2b reflects less than 1% of the light it receives from its parent star. For comparison, Earth's albedo is around 30%.
- Tidal Locking: Like many hot Jupiters, TrES-2b is tidally locked, meaning one side always faces its star.
- High Temperature: Its proximity to its star results in extremely high temperatures, estimated to be over 980 degrees Celsius (1800 degrees Fahrenheit).
- Possible Red Glow: Scientists theorize that the planet might emit a faint, deep red glow due to its extreme heat.
Why is TrES-2b so dark?
The exact reasons for TrES-2b's darkness are still being investigated, but prevailing theories suggest:
- Lack of Reflective Clouds: Unlike many gas giants with highly reflective cloud layers, TrES-2b likely lacks such clouds in its atmosphere.
- Presence of Light-Absorbing Chemicals: The high temperatures in TrES-2b's atmosphere might cause the formation of chemicals like vaporized sodium, potassium, and titanium oxide, which absorb light effectively.
In conclusion, TrES-2b stands out as the darkest known planet, presenting a fascinating puzzle for astronomers trying to understand the diverse properties of exoplanets. Its extreme darkness challenges our understanding of planetary atmospheres and their composition.
