This is another in the Priscilla Hutchins series and I wonder if it's the last. The story has references to all the other books and deals with the Omega clouds, plus the end has a little wrap-up for each character living at the end. If it's the end, I'd like to reread them all.
The Academy that has done a lot of the actual space research is about to close because people are not so interested anymore (like us not going into space so much anymore) when a young physicist shows up and offers them a working Locarno engine. The first trial of the Locarno engine, originally developed by his mentor, failed. He's been able to do more work and he's sure it will work now. The first part of the book is dedicated to getting a ship to put the engine on, getting money, testing it (when suddenly lots of money starts showing up), and then getting ready for a trip to the Cauldron.
The Cauldron is the area near the galactic center that is sending out the Omega clouds, and it's very radioactive. Hutch and four others decide to prove the long distance virtue of an engine that goes so much faster than the original that it's only three months to galactic center. They plan to come out of the Silvestri space three times and visit planets/areas that have had some significance before they could go out there. Things happen, as you might expect, and when they finally make it to the Cauldron and find out the origin of the Omega clouds, people start showing their true colors.
I really like McDevitt's books, so I'm massively prejudiced, but I highly recommend this.