Quote Originally Posted by Jalyha View Post
What's the mass of it's star, though?

I'm a bit concerned if the mass is too great compared to the mass of the star, it wouldn't be able to hold an orbit very close to the star.
IANAP

WASP-18 is an F6 star with an apparent mass about 25% greater than the sun. It's a little bit larger and a little bit hotter than our star, but it's reasonably Sun-like. WASP-16b will probably collide with the star eventually. If it's been spiraling inward for a long time, it may have swept up many of the other planets in that system as it did so: sending them into larger orbits, hurling them into the star ahead of itself, or even absorbing them.

How the presence of a large planet that close to the star would affect potentially life-harboring planets further out is an interesting question. That particular planet would probably block less than 10% of the light coming from the star for maybe half an hour each day (that's a wild guess; I only did some very rough math), which would only slightly reduce the total solar power reaching the biosphere. Even a small change of that kind could have large ramifications, though. The regular partial eclipse would be a noticeable event. Might make for some interesting mythology.

A large planet further away from the star would make the eclipses longer and more dramatic, although less frequent. It might also have the effect of perturbing the inhabited planet's orbit, though.