Does anyone know if there's going to be a fifth edition of this book?

I haven't heard, but I hope so. I've bought a copy of each edition as it came out. I fear a new edition may be impossibly thick, though. For a more up-to-date coverage of Solar System topics, I highly recommend Encyclopedia of the Solar System, 2nd ed., L. McFadden, et al. Eds., 2007.
Tom

Thanks for the thread!

I have 2 of the past editions, and it is definitely past due for me to upgrade!


I'll also take this opportunity to plug Joseph Burns excellent chapter on planetary rings. Read that chapter carefully, and then go review the Cassini Iapetus images.