Astronomers have identified what could be one of the most peculiar known exoplanets. This planet orbits a rapidly spinning neutron star known as a pulsar, which is just the beginning of its unusual characteristics.

Michael Chan and his team at the University of Chicago discovered this strange exoplanet located more than 2,000 light-years away from Earth using the James Webb Space Telescope. They quickly recognized that something was off when they analyzed the spectrum of light emitted by the planet. Instead of detecting the typical signatures of water or carbon dioxide, they unexpectedly found carbon molecules.

Carbon molecules are not commonly seen in planetary atmospheres as they typically bond with other elements rather than themselves. “For carbon to exist in the atmosphere, we would need to eliminate nearly all other elements, including oxygen and nitrogen, which is something we don’t understand how to achieve,” Zhang stated. “There aren’t any other known planetary atmospheres like this one.”

Due to its proximity to its star and the star’s significant mass, the pulsar’s gravity is believed to have distorted the planet into an elongated, lemon-like shape. A year on this exoplanet lasts just 7.8 hours, and even its coldest regions reach temperatures of approximately 650°C (1202°F). Unlike most gas giants, the winds on this planet blow contrary to its rotation. “You can envision this planet having graphite clouds in its atmosphere, giving it a striking red appearance, reminiscent of an ominous lemon,” Zhang remarked. “I consider it to be undoubtedly the most bizarre exoplanet known.”

These numerous anomalies pose a challenge in explaining the formation of PSR J2322-2650b, running counter to established models of planetary formation. For now, this utterly bizarre and remote world remains an enigma.