Raytheon, the Waltham defense contractor, is merging with Connecticut neighbor United Technologies.

The combined company will be headquartered in Greater Boston and become the country's second-biggest in aerospace and defense. We're talking roughly $75 billion in annual sales — more than Lockheed Martin or Northrop Grumman, and second only to Boeing.

So, what does this mean for Massachusetts?

Jon Chesto, Boston Globe business reporter. He tweets @jonchesto.