
We hear plenty about all the exoplanets being studies at the moment, but we hear very little about exomoons, though several astronomers are eager to find them and learn more about them.
This time last year I highlighted a paper that discussed a possible exomoon circling an exoplanet called WASP-49Ab located about 635 light-years away . It was spotted by the European Southern Observatory’s Very Large Telescope in Chile.
Well, now the James Webb Space Telescope (JWST) has provided data related to another possible exomoon orbiting a hot Jupiter-like exoplanet called WASP-39b. It is located about 700 million light-years away.
In a Scientific American article titled “Have Astronomers Finally Found an Exomoon?” we learn that a paper is being released shortly outlining the argument for this potential “hypervolcanic exomoon.” This presumed IO-like exomoon is being cooked by the parent sun.
The paper accepted for publication, Volcanic Satellites Tidally Venting Na, K, SO2 in Optical & Infrared Light, states the following:
Recent infrared spectroscopy from the James Webb Space Telescope (JWST) has spurred analyses of common volcanic gases such as carbon dioxide (CO2), sulfur dioxide (SO2), alongside alkali metals sodium (Na I) and potassium (K I) surrounding the hot Saturn WASP-39 b. We report more than an order-of-magnitude of variability in the density of neutral Na, K, and SO2 between ground-based measurements and JWST, at distinct epochs, hinting at exogenic physical processes similar to those sourcing Io’s extended atmosphere and torus. Tidally-heated volcanic satellite simulations sputtering gas into a cloud or toroid orbiting the planet, are able to reproduce the probed line-of-sight column density variations. The estimated SO2 flux is consistent with tidal gravitation predictions, with a Na/SO2 ratio far smaller than Io’s. Although stable satellite orbits at this system are known to be < 15.3 hours, several high-resolution alkali Doppler shift observations are required to constrain a putative orbit. Due to the Roche limit interior to the planetary photosphere at ~ 8 hours, atmosphere-exosphere interactions are expected to be especially important at this system.
It is a dense summary, but also a hopeful finding that may lead to more focused searches for exomoons.
The addition of exomoons to the list of new discoveries will only increase the chances that some form of life can be found among he many solar systems we can study. Interestingly enough, we are still probing our own solar system’s moons with the same hope.