“Why do you have to go?” Her question registers as the first raindrops begin to fall. You stop in the middle of the sidewalk, tip your face to the sky and let the damp, metallic smell trigger the pleasant memories. Springtime. Green leaves. Hikes along a springy bed of pine needles in the forest.

She turns. The scent of hairspray fights the perfume radiating from her skin. The smell of anger. You add that to your mental catalog of unpleasant memories. “Are you even listening to me?”

“Uh. Sure. Of course.”

“No.” She starts walking again. You follow. Umbrellas pop open all around you. Hers with a tooth-grinding snap. She doesn’t offer to share. “You’re not listening. You’re lost in that damn Mars mission again. Maybe you should go. Maybe you should go now.”

“This ‘damn Mars mission’ could save humanity! Not to be hyperbolic about it, but when the oceans rise and the air is unfit to breathe, when crazy world leaders launch the missiles…what if there was a habitable place we could go? With far more potential than the Moon?”

Silence. You should have weighed your words more carefully. Conversations like this were why she took pills every night to sleep. You try again, softer. “They’ll only need me for a few months.”

“That’s what you said last time.” She spins toward you, flinging a spray of rain from her umbrella across your shirt. “It was more like a year!”

“Then move to Houston with me.”

“Houston. As if.”

The smell of spite. You try to think of happier aromas. Bread baking. A wet dog and a small boy jumping into a pond on a summer afternoon. You smile to yourself. This could really work. In previous extended space missions, humans have suffered from sensory deprivation. It’s made them hallucinate. It’s been detrimental to their health, their productivity.

The team loves your idea—a virtual reality system that can impart not just visuals and sound, but can activate memories tied to certain smells. Now you’re getting the chance to create it. First, catalog the appropriate sensory input, then build the system and test it. You know it can work. You know it will help. You’d feel better if your wife believed in you, believed in your ideas. Believed you weren’t taking these assignments to get away from her.

But you can’t change that.

You spend the trip home in silence. You imagine the smells awaiting you. The stale coffee in the kitchen. The damp wool aroma of the couch where you’ll be sleeping.

You pull into the driveway, snap off the keys. Let out a long breath. She reaches for her door handle, hesitates. “I’ll go with you.” Her voice is so quiet it blends with the rain. Then, a little louder, and with a bit of humor you haven’t heard in some time, she adds, “After all, if you’re going to be so absorbed in this project, someone better make sure you eat once in a while.”