TechBelgian scientists unveil cotton Candy-like exoplanet in cosmic breakthrough

Belgian scientists unveil cotton Candy-like exoplanet in cosmic breakthrough

Earth seen from space
Earth seen from space
Images source: © NASA

8:04 AM EDT, May 16, 2024

A team of scientists from the University of Liège in Belgium has made an intriguing discovery, reported in "Nature Astronomy," of an exoplanet situated approximately 7,460 light-years away from Earth that possesses a density akin to cotton candy. This exoplanet, named WASP-107b, stands out as one of the lightest gas giants discovered to date.

Misnamed initially, the correct designation is WASP-193b. It surpasses Jupiter in size by half yet is seven times lighter. Its composition, primarily of hydrogen and helium, accounts for its exceptionally low density. This composition makes it a rarity, posing the question of how such a planet can maintain stability.

Explaining the uncommon low density

Khalid Barkaoui, the lead researcher, noted that WASP-139b—correctly identified as WASP-193b—is the second least dense planet known, following closely behind Kepler-51d. Despite the abundance of over five thousand exoplanets discovered, its remarkably low density remains an outlier, challenging the bounds of conventional models of irradiated gas giants and suggesting a possible lack of an internal core.

The breakthrough came via the Wide Angle Search for Planets (WASP) project, utilizing automated telescopes globally to pinpoint the planet. WASP-193b orbits its star, WASP-193, every 6.25 days. The research benefited from the collaborative use of the TRAPPIST-South, SPECULOOS-South observatories, and the European Southern Observatory in Chile. Astonishingly, WASP-193b's density is just 0.0037 ounces per cubic inch, a figure that drastically contrasts with Jupiter's density of 0.34 ounces per cubic inch, underscoring the rarity of such a discovery.

The cotton candy comparison

The astonishingly low density of WASP-193b, making it akin to cotton candy, lies in the structure of the material itself. Just as cotton candy is predominantly air, this planet's composition is incredibly light or "fluffy," as the scientists have described.

Typical of gas giants, WASP-193b's primary components are hydrogen and helium, but unusually, these gases form an atmosphere far more expansive than Jupiter's. Current scientific theories fall short of explaining this phenomenon.

The research team speculates that the planet's stability might stem from significant internal energy, though its source remains unknown.

Dr. Barkaoui concludes that WASP-193b is enveloped in mystery, necessitating further observational and theoretical studies. Insights from the James Webb Telescope and comparisons with theoretical models will be crucial to understand the mechanisms behind its unique characteristics.

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