Possible Volcanic Exomoon orbiting WASP 49Ab
Planetary scientists believe that may have discovered a volcanically active exomoon orbiting a Jupiter-size gas giant exoplanet, WASP 49Ab, located over 600 light years from the Earth.
WASP 49 is a binary star system (A/B) located 635 light years (195 parsecs) distant in the constellation of Lepus the Hare (6h4m21.47357s, -16°57'55.1087") with an apparent magnitude of 11.35. The larger star of the binary is WASP 49A that is approximately the diameter and mass of our Sun, spectral type G6V, metallicity Fe/H Index) of -0.23 (59% the Sun's level), and surface temperature of 5,600°K (9,620°F/5,330°C vs the Sun's 5,772°K (9,930°F/5,499°C)), and an estimated age of 11.9 billion years (versus the Sun's age of 4.6 billion years). The smaller star of the binary, WASP 49B has approximately 34% the Sun's mass and s surface temperature of 3,454°K (5,758°F/3,181°C). The pair of stars are separated by 443 AU (41,199 million miles/66,299 million km).
WASP 49Ab is a Jupiter-sized gas giant exoplanet that was discovered by a team led by Monika Lendl (University of Geneva) in August, 2012 using the WASP CCD array by the primary transit method (decrease in the light curve of the star as the exoplanet crosses the star). WASP 49Ab is approximately 12 % larger than the planet Jupiter but with only 40% its mass (making it one of the lightest exoplanets discovered). It orbits the primary star (WASP 49) at an average distance of 0.0379 AU (~3.5 million miles/5.7 million km, or 4% the Earth-Sun distance) in a period of 2.8 days. The orbit of WASP 49Ab is inclined 85 degrees to its primary star. Its equilibrium temperature is 1,369°K (2,005°F/1,096°C) making it a "Hot Jupiter" and far within its habitable zone.
An extensive sodium (Na) cloud was discovered orbiting WASP 49Ab in 2017 by Apurva V. Oza (NASA JPL and now at Caltech). Both WASP-49 b and its star are composed mostly of hydrogen and helium, with trace amounts of sodium. Neither contains enough sodium to account for the cloud, which appears to be coming from a source that is producing roughly 220,000 pounds (100,000 kilograms) of sodium per second. Even if the star or planet could produce that much sodium, it’s unclear what mechanism could eject it into space. As detailed in a new study published in the Astrophysical Journal Letters, they found several pieces of evidence that suggest the cloud is created by a separate body orbiting the planet, though additional research is needed to confirm the cloud’s behavior. For example, twice their observations indicated the cloud suddenly increased in size, as if being refueled, when it was not next to the planet. They also observed the cloud moving faster than the planet in a way that would seem impossible unless it was being generated by another body moving independent of, and faster, than the planet. “We think this is a really critical piece of evidence,” said Oza. “The cloud is moving in the opposite direction that physics tells us it should be going if it were part of the planet’s atmosphere.” While these observations have intrigued the research team, they say they would need to observe the system for longer to be sure of the cloud’s orbit and structure.
https://astrobiology.com/2024/10/does-distant-planet-wasp-49-b-host-volcanic-moon-like-jupiters-io.html
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