Water Is Destroyed, Then Reborn in Ultrahot Jupiters

Imagine a place where the weather forecast is always the same: scorching temperatures, relentlessly sunny, and with absolutely zero chance of rain. This hellish scenario exists on the permanent daysides of a type of planet found outside our solar system dubbed an "ultrahot Jupiter." These worlds orbit extremely close to their stars, with one side of the planet permanently facing the star.

What has puzzled scientists is why water vapor appears to be missing from the toasty worlds' atmospheres, when it is abundant in similar but slightly cooler planets. Observations of ultrahot Jupiters by NASA's Spitzer and Hubble space telescopes, combined with computer simulations, have served as a springboard for a new theoretical study that may have solved this mystery.

Continued...
Source

Credits: NASA/JPL-Caltech/Vivien Parmentier/Aix-Marseille University (AMU)

These simulated views of the ultrahot Jupiter WASP-121b show what the planet might look like to the human eye from five different vantage points, illuminated to different degrees by its parent star.

The images were created using a computer simulation being used to help scientists understand the atmospheres of these ultra-hot planets.

Ultrahot Jupiters reflect almost no light, rather like charcoal. However, the daysides of ultrahot Jupiters have temperatures of between 3600°F and 5400°F (2000°C and 3000°C), so the planets produce their own glow, like a hot ember.

The orange color in this simulated image is thus from the planet's own heat. The computer model was based on observations of WASP-121b conducted using NASA's Spitzer and Hubble space telescopes.

Source / Image Courtesy

This 360° animation depicts planet WASP-121b; an exoplanet with an atmosphere of glowing water. It completes one full journey around its star every 1.3 days - this animation shows this orbit at x5000 speed.

With an atmosphere hot enough to boil iron, WASP-121b is a type of exoplanet known as a 'hot Jupiter'. The planet orbits closely to it's host star, located in the constellation of 'Puppis', about 900 light years away from Earth