Balanced System, A

For the world, it began as a perfectly normal day.  The sun rose, the winds blew clouds over the ocean, and everything was normal.  But one thing was all across the news come midmorning.  Every headline in every newspaper, across every language, said the same thing:

ASTEROID HEADED FOR PLANET

Some top astronomers had discovered a new hunk of space rock the night prior, and while that alone might have led to a few scientific journals publishing the fact, there were two key features about this boulder that set it apart from all the other space junk hurtling through the cosmos.  First, it was one of the largest asteroids ever seen, nearly the size of Texas.  It was so large that it disrupted the gravitational pull of Pluto on its moon as it rocketed between the two, sending them spiraling off.  The second fact was much more disturbing, though:  It was on a collision course with Earth!  Something needed to be done, or scientists predicted that the resulting impact when it struck would wipe out most of Europe instantly and kill off all life due to the damage to the environment mere years later.  Worse still, while it was still three years until impact was set to occur, there was next to nothing anyone could do to stop it.  As more and more scientific communities double- and triple-checked the numbers to show the claim was genuine, riots broke out in the streets and religious fanatics called to the population to repent before the end.

That was, of course, until an alienesque ship appeared in the sky above New York City.  That just made things worse.  However, the ship sent out a broadcast, one that appeared in every electronic device in every language.

[People of Earth.  We are what you would call aliens, a race known as the G'norgath.  'Protectors' would be the closest translation.  We have seen your plight, and the Greater Galactic Community has decided you are advanced enough to warrant saving.  In order to disrupt your incoming meteor, the gravitational force of an entire planet must be used to redirect it.  By our calculations, the technology we have on hand can only do this if action is taken within one Earth month.  We have a special device that can generate enough gas to match your Jupiter, but it needs a vessel so it does not escape into the vastness of space while it gains gravity.  It is a daunting task to require, and we know no individual would want to condemn themselves to this fate, but...

We need a volunteer to become the newest planet of the solar system.]

What followed was a stream of data backing up their claim, the exact specifications of the new 'planet' including size, internal pressure, orbit, and mass, and the blueprints for a communication device to contact the aliens when we were ready with a volunteer.

Much to the surprise of the government and the aliens, hundreds of thousands of people volunteered from around the globe.  A scarce few did it 'to protect humanity' or 'for fame and glory', but the overwhelming majority did it because they had a fetish for being blown up like a balloon to ridiculous sizes.  This led to a new problem, however.  Instead of fighting to not get chosen, now there was a battle for the spot among the eight planets!  Eventually the United Nations decided to hold an international raffle for those willing to give everything up to be the newest gas giant.

In the end, the tickets were drawn, and a young woman named Janet from Ohio was found to be the winner.  A twenty five, spry little woman with long red hair and blue eyes, standing around five feet tall with thin proportions.  "Finally, I can be the size I've always dreamed of," she explained in an interview.

Still, a victory was a victory, and she soon found herself on the alien craft hundreds of thousands of mines from Earth, just beyond the orbit of Saturn.  She held a small pill in her hand.

[Remeber, Janet.  This is for the future of your species.  There is no going back.  We have reached the location and speed to put you in a proper orbit, so when you are ready take it and jump out.]

Janet happily swallowed the pill, and took a running leap out of the ship's artificial gravity.  As the beings had promised, the pill took effect near instantly.  The first thing that she felt was the lack of the freezing temperatures associated with space, and she didn't feel hungry any longer.  She also noticed, as an afterthought, that she was no longer breathing, her body seeming to sustain itself.  And then, from inside her body, she heard the hissing start.  It was quiet at first, growing louder and louder by the minute.  Janet put a hand to her stomach as it bloated out, skin stretching to quickly make her look well beyond pregnant.  Her arms, legs, and the rest of her torso followed suit, blimping out so fast that a normal human would have been torn in half!

But Janet was no longer a human.  She was now the modified shell of a new planet, and she was proud of it.  As she passed blimp size and zeroed in on surpassing an aircraft carrier, she heard the hissing continue to grow as her arms and legs disappeared completely into her spherical body.  Skin stretching tighter and tighter, she at last became visible to Earth telescopes as she passed the size of Texas, finally growing larger than the meteor she was going to stop.

"I can't believe it," she thought.  "This feels so amazing, and I get to stay like this forever!"  Janet grinned as she grew larger and larger, her body swelling to such sizes even she could not comprehend how large she was getting.  Past the size of America.  Past the size of Earth itself!  The impossibly large balloon grew bigger still, exerting her newfound gravitational pull as the gasses within her gravitated towards her core.  It lessened the strain and pressure on her now micrometer-thick, invincible skin as she finally stopped growing, cementing Planet Janet as the largest planet in the solar system, 10% larger than Jupiter.

The world cheered their heroine as the meteor became caught in Janet's gravity and became her first of many moons, and Janet settled into her orbit with a slightly bloated smile on her face.  Finally, she was the perfect size.