Wouldn't it be cool if our speaker was an 80s music fan, and instead of getting jealous, he slid down to his knees as his wife breastfed their son, and busted out Tina Turner's famous song, "What's looooove got to do? Got to do with it? Who needs a heart when a heart can be brooooken?" Okay, maybe not. But love is a central theme to "Dangerous Astronomy." It has a lot to do with it. The familial love of both parenting and marriage becomes the source for closeness and distance for the speaker. Although he deeply loves both his wife and son, he seems isolated and frustrated by the closeness his wife and son have. So finally, he has to turn to his understanding of God to relieve him of his jealousy and accept that love isn't always as easy as it seems it should be.
Through the dramatic unfolding of the speaker's frustration with his wife and son, this poem portrays love as a complex emotion that extends beyond the speaker's control.
In "Dangerous Astronomy", love is a source of isolation and jealousy, rather than comfort and fulfillment. It's bad news.