Planet shows star’s death does not have to doom its worlds, Pg12

Key Highlights:

• The James Webb Space Telescope (JWST) has detected an atmosphere around WD 1856 b, a Jupiter-sized exoplanet orbiting a white dwarf star.
• This marks the first time an atmosphere has been confirmed on a planet orbiting a dead star.
• The atmosphere of WD 1856 b contains hydrocarbons, such as methane, and aerosol clouds.
• The planet was found to be significantly hotter than expected, likely due to tidal heating.
• The discovery suggests that planets can retain their atmospheres and potentially sustain conditions for life even after their host stars die.

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Detailed Insights:

• WD 1856 b is a gas giant with a mass estimated to be between four and eleven times that of Jupiter, or approximately 5.2 Jupiter masses.
• It orbits its host white dwarf star, WD 1856+534, at an extremely close distance, completing an orbit in about 1.4 days (34 hours).
• The white dwarf star, WD 1856+534, is roughly half the mass of our Sun but only about 40% larger than Earth in radius.
• The planet's unexpected warmth is attributed to tidal heating, a process that occurred during its inward migration after the star evolved into a white dwarf.
• WD 1856 b was initially discovered in 2020 using data from NASA's Transiting Exoplanet Survey Satellite (TESS) and the Spitzer Space Telescope.
• This planetary system is located approximately 80 light-years away from Earth.
• The findings offer a glimpse into the potential future of our own Solar System, suggesting that outer planets might survive the Sun's eventual transformation into a white dwarf.

Scientific/Technical Concepts Involved:

• White Dwarf: The dense, Earth-sized remnant core of a star like our Sun after it has exhausted its nuclear fuel and shed its outer layers.
• Exoplanet: Any planet that orbits a star outside of our Solar System.
• James Webb Space Telescope (JWST): A powerful infrared space observatory designed to detect and characterize the atmospheres of distant exoplanets.
• Tidal Heating: The process where orbital and rotational energy is converted into heat within a celestial body due to varying gravitational forces from its primary, especially in eccentric orbits.