huh

The Eleventh Hour

Commander Shepard, sci-fi Cassandra

Shepard hummed a noisy sigh, her breath curling like an almost physical thing inside the bowl of his cowl and along the base of his neck. “You should just sleep here,” she said, so quiet he almost wondered if she meant to say it out loud.

Keeping his voice light, he tried for a joke: “Is that an order?” Even as he said it, it felt clumsy, almost gauche. The air seemed to thicken around him, an extra atmosphere’s worth of pressure.

She shifted against him; the ends of her hair fell against her chin and brushed the sensitive underside of his neck. “No, it’s a request,” she replied. “Nothing formal.” And as her hair brushed again against his hide, he felt an accompanying jump in his stomach. He thought by her tone, by the way she didn’t say it, maybe, she might feel it too. That well of terrifying want.

“You don’t have to if you don’t want to,” she said, filling the space he had left quiet. “I just…”

He ran his knuckles against her side, searching for the bump of her ribs and finding a ridge of scar tissue instead. “If you say I’m welcome—” With just the pad of his thumb, he smoothed over the skin. “I’ll stay.”

These early orbits are unstable, and some planets, planetoids, and minor objects will be attracted to each other and fling out of the system or into highly elliptical orbits. The remnant nebula also exchanges momentum with the planets, and its outward movement is countered by inward movement of those planets. These interactions allow gas giants that formed beyond the frost line to migrate inward into orbits that would normally be impossible for them to form in.

As they navigate inward, they gravitationally attract the terrestrial worlds closer to the star, and pull them out to less habitable regions or toss them out of the system entirely. The gas giants may even be in orbits tighter than Mercury, falling into what's called the hot Jupiter category where the intense heat has puffed out the atmosphere substantially, and is blasting it away from the gas giant. The closer the giant is, the more angular momentum has been exchanged.

So, yes, a system with a tightly orbiting gas giant is substantially less likely to have terrestrial worlds in the habitable zone (where liquid water can exist).