What our measurements so far show us are what we call the spectral absorption features - and its spectrum indicates carbon monoxide and or carbon dioxide in the atmosphere.
“It’s already being targeted for observations with the James Webb Space Telescope, which is NASA’s next big multibillion-dollar flagship space telescope that’s going up in a couple of years. “I wouldn’t say we understand everything about this planet now, but we’ve measured enough to know this is going to be a really fruitful object for future study,” he said. “The planet also doesn’t transport much heat to its nightside, but we think we understand that: The starlight that is absorbed is likely absorbed high in the atmosphere, from whence the energy is quickly radiated back to space.”Īccording to Crossfield, the results are just a first step into a new phase of exoplanetary exploration as the study of exoplanet atmospheres steadily moves toward smaller and smaller planets. “The planet is much cooler than we expected, which suggests that it is reflecting away much of the incident starlight that hits it, presumably due to dayside clouds,” said co-author Nicolas Cowan of the Institute for Research on Exoplanets (iREx) and McGill University in Montreal, who helped in the analysis and interpretation of the thermal phase curve measurements. Readings of the the planet's temperature is seen as a way to characterize its atmosphere. We see most of the infrared light coming from the part of the planet when its star is straight overhead and a lot less from other parts of the planet.” But on this planet, it's actually hottest just about at noon. “Infrared light tells you the temperature of something and where the hotter and cooler parts of this planet are - on Earth, it’s not hottest at noon it’s hottest a couple of hours into the afternoon. “We measure how much infrared light was being emitted by the planet as it rotates 360 degrees on its axis,” he said. Crossfield and his co-authors used a technique called “phase curve” analysis to parse the exoplanet’s atmospheric makeup. Hot Neptune LTT 9779b was discovered just last year, becoming one of the first Neptune-sized planets discovered by NASA’s all-sky TESS planet-hunting mission. “A year on this planet is less than 24 hours - that's how quickly it’s whipping around its star. “This planet doesn’t have a solid surface, and it’s much hotter even than Mercury in our solar system - not only would lead melt in the atmosphere of this planet, but so would platinum, chromium and stainless steel,” Crossfield said. While LTT 9779b is extraordinary, one thing is certain: People probably wouldn’t like it there very much. Yet, our Spitzer observations show us its atmosphere via the infrared light the planet emits.”
“This planet is so intensely irradiated by its star that its temperature is over 3,000 degrees Fahrenheit and its atmosphere could have evaporated entirely. “For the first time, we measured the light coming from this planet that shouldn’t exist,” said Ian Crossfield, assistant professor of physics & astronomy at KU and lead author of the paper. The paper details the very first spectral atmospheric characterization of any planet discovered by TESS, the first global temperature map of any TESS planet with an atmosphere and a hot Neptune whose emission spectrum is fundamentally different from the many larger “hot Jupiters” previously studied. The findings concerning the recently found planet LTT 9779b were published today in Astrophysical Journal Letters. LAWRENCE - A team led by an astronomer from the University of Kansas has crunched data from NASA’s TESS and Spitzer space telescopes to portray for the first time the atmosphere of a highly unusual kind of exoplanet dubbed a “hot Neptune.”
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