In an astronomical breakthrough, the James Webb Space Telescope (JWST) and the Transiting Exoplanet Survey Satellite (TESS) have captured unprecedented observations of two disintegrating exoplanets. These observations offer a rare glimpse into the interiors of planets, a perspective that has remained elusive, even for Earth. The findings, led by a team of astronomers including Jason Wright from Penn State and Marc Hon from MIT, provide compelling insights into the intense environmental conditions that lead to the rapid disintegration of these distant worlds.
The first of these "disintegrating" exoplanets, K2-22b, is a Neptune-size rocky world orbiting perilously close to its star. Completing an orbit in a mere nine hours, K2-22b is subjected to surface temperatures exceeding 3,320 degrees Fahrenheit (1,826 degrees Celsius), hot enough to vaporize rock. The intense heat from the star literally roasts the planet, causing it to shed material into space. Recent JWST observations reveal that the evaporated rock forms an extended, comet-like tail that spans approximately 5.6 million miles (9 million kilometers) and occupies nearly half of the planet's orbit.
"These planets are literally spilling their guts into space for us." – Nick Tusay
The second exoplanet, BD+054868Ab, presents a similarly dramatic spectacle. As the closest evaporating exoplanet discovered to Earth, it exhibits two massive tails: a leading tail composed of larger, sand-sized particles and a trailing tail containing smaller, soot-sized grains. The planet is losing material at an alarming rate, equivalent to a moon's worth every million years. Researchers predict that BD+054868Ab will cease to exist in about one to two million years.
"The rate at which the planet is evaporating is utterly cataclysmic, and we are incredibly lucky to be witnessing the final hours of this dying planet." – Marc Hon
These discoveries were made possible through the combined efforts of TESS and JWST, which observed thousands of stars to detect subtle periodic dips in light caused when a planet transits in front of its star. The study of these planets not only showcases the capabilities of these space telescopes but also presents a unique opportunity to understand terrestrial planet interiors.
"It's a remarkable and fortuitous opportunity to understand terrestrial planet interiors." – Jason Wright
