Celestial Bodies

Planet formation models suggest that small planets are regularly flung from their solar systems by close encounters with neighboring gas giants. … A new model suggests that submarine aliens on such a planet could have a chance at survival.

– Lisa Grossman, “Rogue Planets Could Harbor Life,” Wired Science

So there I was, a new gas giant just waking up. The disk of nebular dust surrounded me like a fresh blanket of snow. Along with the rest of the planets, I marched around that dust cloud, absorbing everything I could, growing and loving every second.

Then I saw her.

A tiny, dainty thing. Rocky, hard, solid, not at all like me, all swirls and ionized storms. She was closer to the sun, and she shone so brightly in that golden light, like a spinning jewel.

I was instantly smitten.

She was young, fiery, and hot-tempered (and in truth, I suppose I was then too). Volcanoes erupted constantly all over her surface, and she spun so fast. Gliding along in our separate orbits, we flirted, argued, got to know each other. For hundreds of millions of years, we danced our teasing dance: closer, further apart, closer again.

I loved her for her fearless embrace of the universe. Back then, the Oort cloud sent hailstorms of comets toward the heart of the solar system. She did not shrink from them but laughed as the great balls of ice struck against her, singing all the while. She hummed as the ice melted, boiled against her skin, rained down and collected into rivers, lakes, seas.

Before I knew it, she had grown into a young planet of great beauty. Her blue oceans swelled and filled out gracefully, and the tan continents drifted over them like sunspots. Still tempestuous and moody, lightning flashed in her atmosphere, studded by speeding cumulonimbus clouds. At her poles, shifting auroras lit up the darkness, dazzling even at my distance.

Finally, I worked up the courage to ask her to join me in my orbit. I even made a ring out of the prettiest bits of drifting dust. “We have been dancing long enough,” I said. “Come, and let us travel together, inseparable until the end of time.”

She glowed, brightened, but then tilted her axis ever so slightly. “Look,” she said, and opened her cloud-cover a sliver so that I could see.

Her oceans were teeming with tiny things, creatures that moved on their own. They dove and swam, chased each other and leapt out of the waves, as fleeting as flashing meteors.

“Sometime ago, a lightning struck the sea just so and formed a chain of complex organic molecules. At first, I didn’t pay much attention to it, but it multiplied and grew. During the eon while you and I danced to the fixed measures of gravity, that simple beginning has evolved into these beautiful and wondrous forms.”

“I don’t understand,” I said. “What do these … things have to do with us?”

“They’re fragile,” she said, her surface brightened again with that lovely, gentle glow. “I have to stay where I am so that they’ll be warm and safe.”

“Then I’ll join you.”

She wobbled in surprise. “No! Your radiation … I’m sorry, but we can’t be together. I have responsibilities now.”

I couldn’t believe it. She was choosing a bunch of parasites over me.

I shouted and spun, and storms, each as big as she was, raged across my surface. But she just ignored me, and continued to tend to her babies, to life.

Something happened to me then. Maybe it was the pull of another star passing by, or a friendly gas giant that wandered closer to offer me comfort, but I shuddered and left my old path.

Now my travels were at an angle to the plane of the solar system. My orbit grew erratic, eccentric. I dove closer to the sun than even she did at perihelion, and flew as far away as the Oort cloud at aphelion. By turns I froze and burned. I approached her, imploring her to accept my devotion, and I ran from her, driven by despair.

I could see that my mass was affecting her, nudging her from her orbit.

“Stop,” she pleaded. “Please. You’re hurting the life dependent on me.”

But I didn’t stop, and I grew even more reckless. During one of my approaches, I finally moved too close, and she fell into my gravity well and was flung out of her orbit.

She drifted away from the sun on an ever-widening spiral.

As she passed me, she turned her face away. I could see a veil of ice forming over her once-clear blue oceans.

“I’m sorry!” I cried after her.

For a moment I saw her shudder, as her molten core grew hotter under the tidal forces of the sun’s gravity and mine. “I have to save them,” she murmured. “I have to save my babies.”

The veil of ice soon covered all of her and grew thicker. And as she continued on her trajectory away from the sun, I could see her atmosphere turn directly into ice and fall onto her like a blanket of dry snow.

I understood. She was willing to entomb herself away from the universe just so that life could continue to survive in her liquid oceans, heated by the fire of her core from below and protected from the void above by miles of ice.

“Goodbye,” I said.

And I saw her ice shell crack just a bit, and a miles-long flow of magma oozed out, a blood red wound hissing against the ice.

“Goodbye,” she said, already so far away.

In a moment the magma froze solid again and sealed the crack, like a scab. I’ll never forget that sight. It was her heart, bleeding with pain and love.

I watched until she disappeared into the emptiness between the stars.

But I know she’s still out there, dreaming under her ice shell, her heart ever fiery, giving life to a whole world.

* * *

Author Note: This story is based on the ideas in the following paper: Abbot, D. S. & Switzer, E. R. “The Steppenwolf: A proposal for a habitable planet in interstellar space” arXiv:1102.1108v2 [astro-ph.EP].