KELT-9b Is A Giant, Hot Exoplanet With Iron And Titanium In Its Atmosphere

Researchers have detailed the atmosphere of a giant, incredibly hot exoplanet called KELT-9b. Using the HARPS-North spectrograph located on the Telescopio Nazionale Galileo in La Palma, Spain, experts were able to discern the exoplanet's atmospheric properties, identifying iron and titanium vapor. The composition is the result of KELT-9b's incredibly hot temperature.

The study was recently published in the journal Nature, where researchers explain that KELT-9b is a giant gas planet orbiting around KELT-9, a star in the Cygnus constellation that is nearly twice as hot as our own Sun. KELT-9b is likewise incredibly hot, orbiting its star at a distance that is 30 times closer than Earth is to the Sun; the exoplanet is more than 4,000 degrees as a result.

The very hot temperatures have presented a mystery: what kind of atmospheres exist on these planets and how do they form? Using simulations, experts with NCCR PlanetS found that KELT-9b's atmosphere should have molecules in their atomic form due in part to the high heat. According to Phys, the simulations also indicate that existing telescope technology should be able to detect iron vapor in KELT-9b's atmosphere.

Such a process involves observing light from the planet's star as the planet itself moves in front of it, resulting in the observed light passing through the celestial body's atmosphere. Using the aforementioned spectrograph tool, scientists were able to analyze the light filtering through the atmosphere, learning things about its properties in the process.

In addition to detecting the iron vapor, researchers also picked up the signature for titanium vapor in the exoplanet's atmosphere. The presence of the vapors is due to the radiation from its nearby ultra-hot star, which breaks apart molecules — it also results in favorable conditions for studying this type of ultra-hot exoplanet.