Space research has made a groundbreaking discovery by identifying a phenomenon similar to a rainbow on a planet outside our solar system for the first time in history. The European Space Agency’s CHEPS satellite captured stunning color rings of light on the WASP-76B exoplanet, situated hundreds of light years away. Resembling Jupiter, this planet is renowned for its extreme conditions, being tidally locked to its star, experiencing scorching temperatures, and enduring rapid rains of molten iron.
Known as the “Effect of Glory,” this phenomenon was previously observed on Earth and Venus when light passes through water droplets in clouds or fog, creating an optical effect resembling a rainbow halo. According to astronomer Olivier Demanjon of the Institute of Astrophysics and Cosmic Sciences in Portugal, specific conditions such as nearly perfect spherical atmospheric particles that are uniform and stable are required for this effect to occur over an extended period.
WASP-76B orbits a star that is 50% more massive and 500 degrees Celsius hotter than the Sun. Being tidally locked, one side of the planet is constantly exposed to sunlight, resulting in extreme heat. These conditions cause the planet’s atmosphere to heat up to 2000 degrees Celsius, expanding six times larger than Jupiter. Interestingly, iron rains occur on WASP-76B due to the temperature disparity between its day and night sides, with iron melting during the day and condensing into clouds that move towards the cooler night side.
After monitoring WASP-76B for three years, the CHPS satellite detected a significant increase in light at the boundary between the day and night sides. Scientists suspect this unusual light may be attributed to strong, localized, and direction-dependent reflection known as the effect of glory. To validate this hypothesis, additional evidence is required, with plans to utilize instruments aboard the James Webb Space Telescope and the upcoming European Space Agency mission Ariel in 2029 to conduct the first comprehensive chemical analysis of exoplanets.