The Jovian football

In exoplanet news, the Universitäts of Bern and Geneva report on a rugby-ball planet. You can tell they're Euros . . .

This planet, 1.5 Jupiter mass, transits WASP-103 relative to us so has a tightly-bound orbit. They can tell its shape from its shadow: it is elongated toward the edges of its sun's disc. So it is pointed toward the sun (and away from it). Tidal forces, then; like those predicted near an Event Horizon: the central body pulls harder on the orbiter's near side than on the far side. Just like how our own Moon draws the ocean's tides toward itself as it runs around Earth (and away from it).

The rocks on Earth don't feel these lunar tides - thankfully. (You gotta go to Io for that.) One Augustus E. H. Love floated a constant for various materials which decides to what extent a ball of that material will react to a given tidal force. This is called, naturally, the Love Number. WASP-103b's Love looks like Jupiter's. With that 1.5J mass it should be denser than Jupiter assuming the same substance... but, it is hotter where WASP-103b is at, than Jupiter is 5.2 AU from our sun. That must be inflating the football. Unlike Io and Earth, the tides should be constant so they don't add to the heat so much. I trust they've done the maths although, they admit, there's still an error-bar here.

The Swiss want to use the James Webb to learn more. Which luckily for them, is now unfolded and just needs to be inserted into L2 for cooldown.