For centuries, mankind has been watching the skies, noting the movements of the heavenly bodies, and sorting out how it all works.
Then a planet like Wasp-18b comes along and throws a spanner into the works.
As related in an article from Sunday’s Los Angeles Times, this particular planet has a number of standout qualities: It’s a “hot Jupiter,” a gas giant that’s exceptionally close to its star; it has an incredibly short orbit, taking less than one Earth day to complete; and, by all accounts, it should’ve fallen into that star and burned up a long, long time ago.
That, at least, is the conclusion of astrophysicist Coel Hellier of Keene University in Staffordshire, England, who discovered Wasp-18b.
“This planet should spiral inwards on such a short time scale that the likelihood of seeing it is very low,” Hellier told the newspaper.
Which raises a lot of questions in the astrophysics community. For example, it could be that the star around which Wasp-18b is orbiting (which is called, coincidentally, Wasp-18) has about 1,000 times less energy than scientists believe. Or it could be that the planet has only been in that orbit a short time and that Hellier happened to catch it there as it gradually spirals into the star. But each of those propositions raises other questions.
Meanwhile, those looking for answers can start closer to home. One of the two moons orbiting Mars, Phobos, is in a similar situation: it’s far closer to the planet than it should be (5,600 miles) and still maintains its orbit.