Illustration of exoplanet LHS 3844 b, a rocky planet with a diameter 1.3 times that of Earth orbiting 0.006 astronomical units from its cool red dwarf star. The planet is hot, with dayside temperatures calculated to be greater than 1,000 degrees Fahrenheit (greater than about 525 degrees Celsius).

Illustration comparing rocky exoplanets LHS 3844 b and 55 Cancri e to Earth and Neptune.

Possible thermal emission spectrum of the hot super-Earth exoplanet LHS 3844 b, as measured by Webb’s Mid-Infrared Instrument. A thermal emission spectrum shows the amount of light of different infrared wavelengths (colors) that are emitted by the planet. Researchers use computer models to predict what a planet’s thermal emission spectrum will look like assuming certain conditions, such as whether or not there is an atmosphere and what the surface of the planet is made of.