Eternal Sunrises and Sunsets: What the James Webb Telescope Discovered on a Distant World

he James Webb Space Telescope The follower a pot Launching an unprecedented investigation into sunrise And eternal sunset in outer planets Far. This pioneering study focuses on worlds orbiting close to and facing their host stars. Extreme heat and radiation conditionsWith these observations, astronomers hope to learn more. Details about the atmospheric composition and habitability of these planets.great progress in understanding Planetary environments outside our solar system.

Researchers using NASA’s James Webb Space Telescope have finally confirmed what models previously predicted: an exoplanet has been discovered. Differences between eternal morning and eternal evening. Wasp-39BIt is a giant planet with a diameter 1.3 times larger than Jupiter, but with Mass similar to Saturn’s masswhich orbits a star about 700 light-years from Earth, is tidally locked to its parent star. a pot It’s a statement.

In this sense, they highlighted that this means this. The outer planet “has a fixed day side and a fixed night side.”That is, one side is always exposed to its star, while the other side is always surrounded by darkness. Now with him Advanced infrared technologycaptured by the Webb telescope Detailed data About this atmosphere, such as Temperature patterns and chemical compositionIn this way, experts can study the atmospheric changes that occur in these cycles, as preliminary results indicate the presence of complex molecules and atmospheric dynamics that challenge current theories about planetary formation and evolution.

This Webb Telescope research project seeks to: Expanding knowledge about exoplanets It has great effects on Searching for extraterrestrial lifeBecause analyzing these planetary differences can allow scientists to pinpoint them. Indicators of biological processes and habitable conditions.

According to the press release issued by NASA, in order to conduct this study, which was published in natureScientists used a NIRSpec (Near Infrared Spectrometer) From the web, which allowed them to confirm “a The difference in temperature between eternal morning and eternal noon At WASP-39B, it looks like the afternoon is about to end. 200 degrees Celsius Warmer. “They also found evidence of different cloud cover, and the part of the planet where mornings are always cloudier is likely to be cloudier than afternoons.”

The astronomers studied the 2- to 5-micron transmission spectrum of WASP-39 b, a technique that analyzes the exoplanet’s dividing line, the line that separates the day side from the night side. They compared the starlight filtered through the planet’s atmosphere as it passed in front of the star with the unfiltered starlight when the planet was next to the star. This comparison allowed them to obtain Information about the temperature, composition, and other properties of the planet’s atmosphere.

Nestor Espinosa “The exoplanet researcher at the Space Telescope Science Institute and lead author of the study said:WASP-39 b has become a kind of reference planet. In studying the atmospheres of exoplanets with Webb. He has puffy and spongy atmosphere“So the signal from starlight leaking through the planet’s atmosphere is very strong.”

Previously published Webb spectra of WASP-39b’s atmosphere revealed Carbon dioxide, sulfur dioxide, water vapor, and sodium at the boundary between day and night, without differentiation between the two sides. he New analysisThen divide this limit into two semicirclescorresponding to the afternoon and morning. The data indicate that The afternoon is noticeably hotter.where the temperature is about 1,450 degrees Fahrenheit (800 degrees Celsius), while the morning is relatively cooler, at 1,150 degrees Fahrenheit (600 degrees Celsius).

“It’s truly amazing that we’re able to resolve such a small difference, and it’s only possible because of Webb’s sensitivity to near-infrared wavelengths and its very stable optical sensors,” Espinosa said in a NASA press release. “Any small movement of the instrument or observatory while collecting data would severely limit our ability to make this detection. It has to be extremely precise, and that’s the case with Webb.”

Comprehensive modeling of the data obtained allows researchers to investigate the structure of WASP-39 b’s atmosphere, its cloud cover, and why the nights are warmer. Although future studies will investigate how cloud cover affects the temperature, astronomers have confirmed that the rotation of gas around the planet is the main reason for the temperature differences in WASP-39 b. On this exoplanet, The hotter gas moves from the day side to the night side via an equatorial jet stream, generating high-speed winds due to the large difference in air pressure.

Because of general rotation models, astronomers have discovered that the prevailing winds in WASP-39b move from the night side to the day side and back again. This makes Morning break is cooler than evening breakWhere the cold air is received from the night side, while the evening side receives warm air from the day side. Wind speeds on WASP-39b can reach thousands of miles per hour.

In this sense, Espinosa said: “This analysis is also particularly interesting because it obtains three-dimensional information about the planet that has never been obtained before. As we can say that the edge of the night is hotter, it means that it is a little swollen. So, theoretically, there is a small spike in the terminator approaching the night side of the planet.

Now, researchers plan to use the same analysis method to study atmospheric differences among other tidally locked hot Jupiters, as part of the Webb Cycle 2 program; WASP-39 b was one of the first targets Webb analyzed when it began science operations in 2022.