There are differences in the morning and evening atmosphere. Thousands of planets around stars outside our solar system have been confirmed through a variety of different methods. Astronomers are learning more about the atmospheres of exoplanets with the help of NASA. The most recent? For a distant world 700 light-years away from Earth, the atmospheric differences between the morning and evening on a tidally locked exoplanet are an incredible achievement.
The models have previously predicted that an exoplanet has differences between its morning and evening atmosphere. WASP-39 b, a giant planet with a diameter 1.3 times greater than Jupiter, is locked to its parent star. One side of the planet is always exposed to its star, while the other is always shrouded in darkness. The eternal morning and eternal evening on WASP-39 b were found to have different temperatures, with the evening appearing hotter than the eternal morning. The forever morning portion of the planet was likely cloudier than the evening.
There have been advances in atmospheric studies.
Astronomers analyzed the 2 to 5-micron transmission spectrum of WASP-39 b, a technique that studies the exoplanets terminator, the boundary that separates the planet's dayside and nightside. A transmission spectrum is made by comparing starlight from a planet to starlight from another planet. Researchers can get information about the planet's atmosphere when they compare it to another planet. The atmosphere of WASP 39 b has become a benchmark planet in studying the atmosphere of exoplanets with the help of the Space Telescope Science Institute. The signal from starlight filters through the planet's atmosphere and is strong.
The temperature and atmospheric composition are analyzed.
There was no attempt to distinguish between one side and the other when the atmosphere of WASP 39b was published. The new analysis splits the day/night boundary into two semicircles, one from the evening and the other from the morning. The evening is 1,450 degrees Fahrenheit (800 degrees Celsius) and the morning is 1,150 degrees Fahrenheit (600 degrees Celsius).
The small difference is only possible due to the extremely stable photometric sensors, and it is stunning that we are able to figure it out. It would be very difficult to make this detection if we had a tiny movement in the instrument or observatory.
Researchers can investigate the structure of WASP-39 b's atmosphere, the cloud cover, and why the evening is hotter by modeling the data. Astronomers have confirmed that gas circulation around the planet is the main cause of the temperature difference on WASP-39 b.
As the planet rotates around its star, hotter gas from the dayside should move through the evening to the nightside via a powerful jet stream. The air pressure difference would cause high wind speeds since the temperature difference is so extreme. The prevailing winds are likely to move from the night side to the day side across the morning and evening terminators using General Circulation Models. The morning side of the terminator is cooler than the evening side because winds of air hit the morning side on the night side. The wind speeds on WASP-39 b can reach thousands of miles an hour.
The evening edge is a little puffsier because we can tell that it is hotter. There is a small swell at the terminator approaching the nightside of the planet
The results have been published in the journal Nature. The WASP-39 b was one of the first targets analyzed by the telescope. There are terminators on the exoplanet WASP-39 b. There is a DOI of 10.1038/s41586-024-0776.
The European Space Agency and the Canadian Space Agency are involved in the project. The new scientific successor to the Hubble Space Telescope is designed to provide unprecedented resolutions and sensitivities. Astronomers can study every aspect of the history of the universe, from the beginning of the universe to the evolution of our own Solar System. The second Lagrange point is where the JWST will explore a wide range of scientific questions, helping to uncover new insights into the universe.