Line #3 Analysis/ConvenientlyClosePlanet


1	As stated on the trope's main page the main reason why the Conveniently Close Planet pops up and fails in RealLife is the ''[[SciFiWritersHaveNoSenseOfScale humongous size]]'' of space. Simply put, distances up there are so vast that are beyond our comprehension as we do not find them in our daily life and, needless to say too, if a ''Franchise/StarTrek''-like show had to spend weeks just going from planet to planet (and that just within a given solar system, never mind interstellar travel) things would be more boring.[[note]]Unless the show focused on the life of the ship's crewmen far more than on her journeys. Of course we're leaving aside [[FasterThanLight FTL]] travel.[[/note]]
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3	In the Analysis page of the AsteroidThicket trope there's a scale-down model of the Solar System to show the real emptiness of the asteroid belt where the Sun ended up as a sphere with a diameter of almost 15 meters. Let's expand this model to the entire Solar System and we'll find that, to cite just some planets, Mercury would be orbiting at roughly 600 meters of the Sun, Venus would lie at 1.1 kilometers of the daystar, Earth at a bit more than 1.5 kilometers away, Mars at around 2.2 kilometers, Jupiter at 8 kilometers, Saturn at almost 15 kilometers, Uranus at roughly 30 kilometers, and finally Neptune at almost 47 kilometers[[note]]Remember that Pluto [[PlutoIsExpendable is just a minor planet]][[/note]]. The sizes of all those planets at scale?. Well, Mercury would have a diameter of just 5 centimeters (ie: the size of a mandarin orange), Venus would have the size of a compact disc (a diameter of 12 centimeters), Earth would be 13 centimeters across (a bit larger than a compact disc), Mars would be a larger mandarin orange than Mercury (7 centimeters across), Jupiter a big beach ball with a size of almost 1.5 meters, Saturn a smaller beach ball with a diameter of 1.2 meters (the main part of its rings would have a diameter close to 3 meters), and finally Uranus and Neptune would be smaller beach balls, with diameters of around 50 centimeters. Consider the distances between them given before and you can understand why we see other planets without optical aid as stars[[note]]To be fair, there're reports of people with an eyesight so sharp that have been able to spot Venus' crescent when it's the closest to us but that's the exception[[/note]] and how an alien ship that was transversing the Solar System at random would be ''extremely'' lucky to pass close to a planet or even the Sun (barring aside the possibility of the Daystar attracting it).[[note]]The closest star would be at this scale ''421,000 kilometers away'', farther than the Moon. Happy motoring.[[/note]]
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5	Just as planetary ring systems are the closest thing in RealLife to an AsteroidThicket, the moons of giant planets are the closest thing to this trope the Universe offers us at least in the Solar System. For example, among UsefulNotes/TheMoonsOfJupiter Io and Europa can approach up to 249,000 kilometers apart and in UsefulNotes/TheMoonsOfSaturn Enceladus and Mimas can be so close as 53,000 kilometers in both cases well within range of our technology in what refers to manned spacecraft[[note]]Of course to send a manned ship to Jupiter or Saturn is something ''far'' more complicated.[[/note]] and close enough that the Mark I eyeball would see from one of them the other as a body large enough to show phases and its most important surface features, just as happens with the UsefulNotes/TheMoon as seen from Earth. Nonetheless they'd be much smaller than those drawings in comic books and the like where a moon fills a considerable amount of sky.[[note]]Of course the parent planet ''would'' appear large, but since Jupiter and Saturn are big ones that's to be expected.[[/note]]
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7	Outside the Solar System some planetary systems are far more compact than ours and you can find in them several planets, including worlds larger than Earth and up to Jupiter-sized ones, crammed within the radius of Mercury's orbit and even much less.[[note]]It's unknown why our Solar System has no close-in planets but a proposal is that planets would have formed there, just to be destroyed by Jupiter migrating inwards and messing with their orbits.[[/note]] Such is the case of the recently discovered [[https://en.wikipedia.org/wiki/TRAPPIST-1 TRAPPIST-1]] where ''seven'' Earth-sized worlds orbit a small star within a radius of 10 million kilometers (1/6th the radius of Mercury's orbit); if you were in one of the planets of that system, you'd be able to see the closest ones as distinct worlds showing phases -those that orbited the star closer than yours- and details. However, as the Solar System examples above, they'd be small (more or less as large as we see the Moon from our planet). Said worlds ''in astronomical scales'', not in Earth ones, are quite close one to each other and an hypothetical civilization that appeared in one would have relatively easy to expand across them.[[note]]Imagine the possibilities that could give several planets so near anong themselves in what refers to life, such as hardy, small lifeforms (the equivalent of bacteria) being sent to space in rocks thanks to [[ColonyDrop large asteroid impacts]] and reaching another planet of that star system.[[/note]] But even those systems are quite distant from the ConvenientlyClosePlanet trope; TRAPPIST-1 at the scale we're using would be seven roughly compact disc-sized spheres separated one from the other by roughly 15 meters orbiting a beach ball, and a ship that came in a random trajectory would be fortunate to pass very close to one of those celestial bodies.
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Context Analysis / ConvenientlyClosePlanet