Abu Dhabi: “The Gulf”
Research scientist Jasmina Bličić and Associate Professor Ian Dobbs-Dixon from the Center for Astrophysics and Space Sciences (CASS) at New York University Abu Dhabi, in collaboration with the works by the James Webb Space Telescope team, for early detection of exoplanets, to observe important features.
In a study recently published in the journal Nature Astronomy, researchers showed how they used the telescope’s mid-infrared instrument (MIRI) capabilities to observe the gaseous planet WASP-43b over a complete orbit of about her star. During this study, which was carried out in the first year of the telescope’s operation, the researchers observed temperature variations around the entire planet, and came to important conclusions about the climate of the planet They found dense clouds and an unexpected lack of methane on the night side of the planet, and traces of water throughout the atmosphere. This is the first time that the presence of clouds has been shown on the night side of the planet, and they were seen at much higher altitudes in the planet’s atmosphere, compared to clouds on Earth.
WASP-43b is similar to Jupiter in size and mass, but is very different in other respects, as its star, which is 86 light years away from our solar system, is cooler and redder than our sun. The planet rotates very close to its star and at a speed so fast that it completes the orbit in only 19.5 hours. This closeness causes the rotation of the planet to coincide with its orbit, with one side always facing the star, just like the Earth and the Moon. As a result, half of the planet (the day side) is always lit and very hot, while the other half (the night side) is always dark and cooler.
Bličić said: “We observed this planet while it was orbiting its star using an infrared spectrometer, so we could study the light coming from different regions of the her atmosphere This allowed us to distinguish the temperature on its sides, and to check for the presence of clouds and different particles. Different chemicals absorb light at different infrared wavelengths. “By combining this fact with our observations over the entire orbit, we were able to determine the chemical composition, cloud cover and heat redistribution fluxes throughout the entire atmosphere and draw conclusions do about the planet’s climate.”
The team found that the day side of the planet, which is always lit, reaches a temperature of 2,285 degrees Fahrenheit (1,250 degrees Celsius), while the night side of the planet, although always dark , still very hot, reaching 1,115 degrees Fahrenheit. (600 degrees Celsius).
“The lack of direct sunlight on the night side of the planet causes a large difference in temperature between the two sides of the planet, which leads to the formation of strong winds,” said Dobbs Dixon, an expert in 3D atmospheric models and redistribution of heat. systems in exoplanets. While winds on Earth are created in a similar way due to changes in temperature, WASP-43b’s proximity to its star results in large differences in temperature, causing a- out winds with speeds of thousands of kilometers per hour, which are much faster than those. on Earth, which largely contributes to heat distribution and general planetary climate formation. “
Furthermore, comparing heat maps with complex three-dimensional models of the atmosphere showed that this temperature change is greater than would be expected in a cloudless atmosphere, and this show that the night side of the planet is surrounded by a thick layer. of clouds that block much of the infrared rays. Unlike rain clouds on Earth, clouds on this very hot planet are made up of rock and mineral dust.
Surprisingly, despite this thick layer of clouds, the research team also found clear signs of water on the night side of the planet, allowing them to determine the height and thickness of the clouds for the first time, and the height and to determine their unusual density compared to the Earth’s Clouds. The researchers also found a mixture caused by winds, called “chemical imbalance,” which quickly transports gas throughout the atmosphere, so that the chemical composition of the atmosphere around the entire planet like
