This giant exoplanet is so deformed it looks like a football

In the search for planets beyond our solar system, astronomers have found a giant exoplanet that looks more like a football or rugby ball than a sphere.

The planet, called WASP-103b, is one of the extremes. Located about 1,225 light-years from Earth in the constellation Hercules, the planet is nearly twice the size of Jupiter.

The strange world is also 50 times closer to its star, WASP-103, than Earth is to the sun. It makes a complete orbit around it in just under an Earth day. With its scale and short orbit, this gas giant is classified as the “hot Jupiter” planet.

The planet was first discovered in 2014 and was observed using the Hubble and Spitzer space telescopes. The researchers wanted to get another perspective on WASP-103b using Switzerland’s joint mission and the European Space Agency’s CHCharacterising ExOPlanet Satellite (CHEOPS) satellite, to combine it with previous observations.

The satellite, launched in 2019, looks for potentially habitable planets. It detects planets using the transit method, that is, measuring the dips in stellar brightness when a planet passes in front of a star.

When astronomers watched WASP-103b pass in front of its star, they were able to see the planet’s strange shape, similar to a football.

A study detailing the findings was published Tuesday in the journal Astronomy & Astrophysics.

“After observing several so-called ‘transits’, we were able to measure the deformation. It’s amazing that we were able to do this – it’s the first time such an analysis has been done,” said study co-author Babatunde Akinsanmi, a postdoctoral researcher at the University of Geneva in Switzerland, in a note.

The role of ocean tides

The researchers suspect that the elongated shape is due to the force of the massive tides that occur on the planet.

On Earth, ocean tides are largely the result of the moon’s gravitational pull. This force causes low and high tides, but nothing dramatic enough to be visible from space.

“Because of its close proximity to its star, we already suspected that very large tides are caused on the planet. But we haven’t been able to verify that yet,” study co-author Yann Alibert, a professor of astrophysics at the University of Bern in Switzerland, said in a statement.

The planet’s deformation also allowed researchers to learn more about its composition, which is gaseous like Jupiter. While the largest planet in our solar system has a frigid average temperature of minus 108 degrees Celsius, this planet is likely inflated due to the heat of its incredibly close star, which is why it’s considered a “hot Jupiter” planet. His star is about 200 degrees hotter and 1.7 times bigger than our sun.

Astronomers want to investigate another mystery about the planet. Normally, a massive planet like this one orbiting close to its host star would gradually approach it and, over time, be engulfed by it. Current measurements seem to suggest that the planet is moving away from, rather than approaching, its star.

Future observations could help astronomers find out more about the internal structure and deformation of the planet, as well as any similar exoplanets. Hot Jupiters proved to be common during early exoplanet detection, but warped planets are incredibly rare.

Previously, the Hubble Space Telescope revealed that the extreme heat and intense gravity of its star is warping another planet, called WASP-121b, into the shape of a football.

“This improves our understanding of these so-called ‘hot Jupiters’ and would allow a better comparison between them and giant planets in the Solar System,” study co-author Monika Lendl, assistant professor of astronomy at the University of Geneva, said in a note.