Conveniently Close Planet

The Earth and the Moon to scale.

"Space is big. Really big. You just won't believe how vastly, hugely, mind-bogglingly big it is. I mean, you may think it's a long way down the road to the chemist, but that's just peanuts to space, listen..."

Space is huge, and the distances involved are far beyond normal human experience. On Earth, if your car breaks down on a country road, you can reasonably expect a rest stop or a gas station within 50 km (ca. 30 miles). Space, however, is not like that country road. If you set your space RV in a randomly-selected trajectory and continue going straight until you get within 50 million kilometers of a star, the chances are (quite literally) astronomically high that you will reach the edge of the galaxy, keep going, and never enter another galaxy... ever. For another example, every planet orbiting the sun (including the likes of Jupiter and Saturn) could easily fit between the Earth and its own moon. That's how few planets there are in our big solar system.

This problem exists even for space travel restricted to within a solar system. Objects travel in orbits and don't occupy the same place all the time - planets orbit their sun, and other objects orbit something else that orbits that sun. A planet does not occupy its entire orbit at once, either. For example, the position of the Earth in its orbit during June and the position during December is a difference of 300 million kilometers. A space traveler who doesn't check his Earth calendar might be in for an unpleasant surprise. Add to this the fact that the sun itself is in orbit around the center of the galaxy, and the galaxy is also in motion, and things become rather complicated very quickly.

The above in a nutshell: In Real Life, nothing in space is ever close, convenient, or in the same place it was a minute ago.

This does not deter sci-fi writers, though! A chance to visit a Single-Biome Planet or a planet with a dark secret offers far more story options than a spacecraft silently cruising for eternity, running out of power and with a group of mummifying bodies on board.

A subtrope of Space Does Not Work That Way and Artistic License – Astronomy. A common side effect of Sci-Fi Writers Have No Sense of Scale. A sort of Artistic License – Geography, though the term "Geography" isn't usually applied to space because it's so big and different.

If characters not only find a planet but land next to what they're looking for see It's a Small World After All. Keep in mind that having Faster-Than-Light Travel would make things conveniently closer, but carries a laundry list of issues of its own. When asteroids are frustratingly close to each other, it's an Asteroid Thicket. Compare Road Trip Across The Street.


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    Anime and Manga 
  • The very last shot of Eureka Seven shows Earth with a dust ring and the "heart-Renton-Eureka"-carved Moon at a distance roughly the diameter of the planet. In other words, at collision distance.
  • In The End Of Evangelion, the moon is close enough to get splashed with blood upon Lillith's death. As big as she is, and as powerful as the jet of High-Pressure Blood is, that's still conspicuously close.
  • Girls Bravo has Seiren, which has Earth taking up a sizeable portion of its skies on a clear day.

  • Star Wars:
    • The Millennium Falcon is supposed to be the fastest ship in the galaxy... at only 1.5x the speed of light. And yet, somehow, slower ships routinely travel from one side of the galaxy to the other in a matter of hours. The "galaxy" in Star Wars is apparently no bigger than our own Solar system.
    • In The Empire Strikes Back, the Millennium Falcon's hyperdrive is out of commission, meaning they're limited to sublight speeds. No problem, though! Bespin happens to be nearby, apparently a light day away.note 
      • Possibly explained by the Falcon travelling at relativistic speed. The journey might take weeks or months, but those on board would only experience a few days. That would allow time for Luke to actually get some training on Dagobah. That still puts Bespin less than a light-year from Hoth, though.
    • The Phantom Menace features a similar example, where shortly after getting through the blockade around Naboo, the heroes' ship is damaged, and their hyperdrive is not working. They still manage to make it from Naboo, a Republic world, to Tattooine, a very backwater planet, at sublight speeds.
      • Although they may have still used the hyperdrive. The pilot said the hyperdrive was "leaking" and wouldn't make it to Coruscant, not that it had completely failed.
  • In Galaxy Quest, the NSEA Protector is badly damaged, but no worries - there's a conveniently close planet! Considering it's a Star Trek parody, definitely intentional.
    Fred Kwan: Hey, Commander. Listen, we found some beryllium on a nearby planet, and we might be able to get there if we reconfigure the solar matrix in parallel for endothermic propulsion. What'd'ya think?
  • Alien³, it's not known what course the Sulaco would have plotted to return to Earth, but it is very convenient that it should be passing Fury 161 when the titular monstrosity set off the fire alarm and jettisoned the survivors. Though plotting your course specifically so you exit hyperspace near a suitable emergency landing site whenever possible does seem prudent, so probably justified.
    • Which is amusing as Aliens averts this with Ripley's life pod, from the original film, drifting aimlessly in space. It was only by chance that she was found at all and that was ~50 years after her escape.
  • In Planet of the Apes (2001), Mark Walberg travels from an unnamed ringed planet to Earth in what seems like a few minutes (there's no toilet on that tiny spacecraft, so it can't have been very long). Even if the ringed planet was Saturn, that's still pretty danged close.
  • In Spaceballs the Winnebago comes out of Hyperspeed and promptly runs out of gas. Cue nearby desert planet to land on.
  • In Space Camp the space shuttle is unexpectedly launched outside of its launch window into an unplanned orbit - but they still manage to make it to the unoccupied space station for supplies. In Real Life, an orbital rendezvous has to be carefully planned before launch; unless you're very lucky (as in, winning-the-lottery lucky), altering an existing, arbitrary orbit to rendezvous with another orbiting object will require far more fuel than the Space Shuttle carries on board.
  • In Star Trek, the planet Delta Vega is an apparently Class M planet (terrestrial, breathable atmosphere, earthlike gravity) that's far enough away from Vulcan that Kirk is exiled there after the Enterprise has already sped away from the ex-planet and Kirk and Spock have had a long fight about what to do next; it's far enough away from Vulcan not to be pulled into the black hole created by the destruction of Vulcan; and yet it's close enough to Vulcan for Ambassador Spock to be able to see it unaided in the daytime sky, as big as the Moon from Earth, as it implodes. Star Trek does at least have the excuse of the fact that the Enterprise has FTL travel, which would make a brief stop to drop off Kirk much more likely.
    • Word of God says that Delta Vega might not have actually been that close — we only see Spock's unaided view of a large Vulcan in the Delta Vega sky during Spock's mind-meld briefing for Kirk, which was meant to be "impressionistic" (in the words of Roberto Orci). That said, Delta Vega is nonetheless so conveniently located that it manages to service at least three different plot threads.
    • If it were actually that close Scotty would have been feasting on Vulcan takeout instead of complaining about station rations.
  • At the end of Space Cowboys, the satellite's boosters fire on a trajectory that conveniently gets to the moon - and quickly enough that Hawk's air doesn't run out on the way - and then reverse-fire to soft-land Hawk on the Moon...
  • In Another Earth a twin of earth appears near Earth.
  • A Conveniently Close Chunk Of Planet in Superman. Doesn't take Lex Luthor long at all to score a chunk of Kryptonite, despite Krypton having been a planet around another star, which was in another galaxy according to Jor-El's narration during Kal's journey to Earth! Kryptonite Is Everywhere...
  • In Star Trek Into Darkness, the confrontation with the Enterprise and a Big Bad vessel is out near the moon ~250,000 miles out. In pretty much no time at all they are caught in Earth's gravity and end up in Earth's atmosphere. Now it is possible if the Enterprise was drifting fast it could get to earth that quickly, but at the speed it would go through the (only ~200-mile-thick) atmosphere of Earth and smack into the surface in no time at all, barely having a chance to slow down in the atmosphere and think about their situation.
  • Gravity is wonderful on a lot of things, but it has to bow to this trope for its heroine. The Space Shuttle is working on the Hubble Space Telescope not too far from the International Space Station (close enough to get there using only a jet backpack), which is "Only 100 miles" from the Chinese Space Station.

  • In Collective Hindsight, a tale of the Starfleet Corps of Engineers, a runaway ship is on a collision course with a planet, despite how unlikely that would be in reality. The ship even passes through several star systems en route, apparently threading the needle several times.
  • In Star Trek: Vulcan's Soul, the first Watraii escape Romulus and Remus by diving down a wormhole. They emerge within range of a habitable planet, despite their ship's limited supplies.
  • Suprisingly for Star Wars, averted in The Thrawn Trilogy. When Luke's broken hyperdrive gives up during an escape, he's stranded in interstellar space.
  • Unsurprisingly for an astrophysicist-turned-author, Alastair Reynold's Revelation Space Series universe is an excellent counter-example and lampshade of the trope in several ways, to the point of being played as an anti-trope:
    • Within systems, Interplanetary battles take place over the course of months or years as even laser beams and near-light speed projectiles take hours to travel between planets, and battles between spacecraft play out similar to submarine battles, in which a large part of the task is simply attempting to find ones opponent. It is common for actively warring factions to both have relatively peaceful thriving colonies in a single star system, while active fighting takes place completely out of sight in a million kilometer wide no-mans land between. Even within a well populated system some derelict ships simply drift in empty space for decades or centuries before being noticed.
    • Interstellar travel takes place at just below the speed of light, so travel times between even neighboring star systems can be years or decades. This is mitigated for those inside the ship by the relativistic effects of near-light-speed travel, reducing the time they experience to months or years. Still, many passengers and less-essential crew elect to spend at least part of the journey in a state of suspended animation.
    • The small crews required by the massive lighthugger class ships, collectively known as Ultras, generally consist of a motley crew of genetic chimaeras and cyborgs filling their vast amounts of free time with various long-term hobbies and projects, such as watching all films ever produced by humanity in chronological order, and then watching them again played backwards.
    • Particularly long-distance journeys can become quite interesting when crew conflicts arise; mutinies and rogue crew members walling themselves off in a district of the ship for a few decades are not unheard of.
    • On worlds with advanced lifespan-increasing technology, a fair number of your friends and family can be expected to still be alive upon your return, but one will still be gone for a span of years or decades-leaving plenty of time for a planetary civil war to supplant the government and seize your house for use as a museum to the revolution, your idiot nephew to bankrupt your thriving business empire, and/or a plague to appear and run its course. And this is after you arrived at your destination to discover that person you were trying to find moved to a new planet 10 years after you left.
  • E.E. Smith got around this problem by making his ships very, VERY fast (ninety parsecs, or about 300 light years, per hour). He lampshades this trope on one occasion when the hero's ship (stolen from the enemy) has a dodgy FTL drive. His engineer urges him to find the nearest base capable of effecting repairs, since " don't want to be fifty years away from the nearest repair shop instead of fifty miles." The conveniently close planet turns out to be infamous for the lethality of its environment, which routinely kills entities from both sides.
  • Played cautiously straight and lampshaded in The Eternal Flame, the second book in Greg Egan's Orthogonal trilogy. Considering that the entire book takes place on (and around) a Generation Ship in Another Dimension whose dimension of time is analogous to the main cast's perception of space, the scientific importance of capturing a nearby Conveniently Close Asteroid is compounded by the knowledge that they will probably never come close enough to another one to get any use out of it. However, it's also partially subverted by the fact that it does take the crew of the Gnat several days to reach it.
  • Ciaphas Cain: Cain's ship is dragged out of the Warp too early and starts exploding. Since they're still on the fringes of the system, it takes him several very long weeks cramped up in the small survivor pod to get to the planet, where he then faces the comparatively easier issue of finding his way out of an ork-infested desert to civilization.

    Live-Action TV 
  • Stargate SG-1:
    • The human-built starship Prometheus breaks down on her maiden voyage. Fortunately for the crew, there is a planet within a few second hop of their overloaded hyperdrive. It's worth noting, however, that the voyage by sublight engine would have taken longer than the ship had resources left for.
      • Bear in mind, the hyperdrive in the Stargate universe is really fast note . It takes three weeks to travel between the Milky Way and the Pegasus galaxies so a solar system within reach of a short jump isn't that out there.note 
    • In season 4, Teal'c and O'Neill are dragged away from earth, set to drift to Apophis's homeworld the slow way. Lucky thing Jupiter just happened to be on the way, making it both conveniently close and in 2-D Space. However slightly mitigated in this case as the glider's navigational computer plausibly could have plotted a course out of the solar system that included at least one slingshot in order to reduce the fuel cost (like NASA and others do when launching probes to the outer planets and beyond).
    • At the season four finale, the destruction of a sun speeds up their spacecraft, sending it four million light years, where it stops inside another galaxy. The odds of taking a random trajectory out of your solar system and ending up in another solar system are already stated above as huge - the odds of getting to another galaxy at a set distance on a random trajectory are just astronomical.
      • Even more implausibly, Apophis' mothership suffers the same fate and ends up in the same place, they are within sublight range of a star, and a familiar enemy just happens to be nearby.
  • In Stargate Atlantis, in the season 4 opener their spacecraft drops out of hyperspace early, right in a solar system and on a course for an Asteroid Thicket.
  • Stargate Universe: Played with in the episode "Light"; they're drifting aimlessly through space and all hope is thought to be lost, because how unlikely it is for them just to wander across a solar system with a habitual planet. But the (seemingly) intelligent ship they're on plotted a desperate course to a system with three "habitable" (the most survivable one rarely gets above freezing) planets. One character even gives a monologue on just what the chances are. Then it's subverted at the end when a slingshot around another planet has altered their course, avoiding the planets and causing them to head straight towards the sun. Unbeknownst to them at the time, the ship intended this to happen, as it refuels via diving into stars and scooping up stellar material.
  • Firefly takes place in multiple close-together solar systems that, according to the official materials orbit a massive red giant, but it makes a big deal out of how far apart things are. In the episode "Out of Gas", the eponymous ship breaks down in the back of beyond, and the crew is well aware that they are out of range of anything habitable by shuttle.
  • In Space: 1999, the moon is thrown out of the solar system on an uncontrolled trajectory. Nonetheless, it passes close to a different alien planet each week.
  • Doctor Who: On a whole, the show is able to avoid this trope thanks to having a ship which teleports and time-travel.
    • In the serial "The Daleks' Master Plan", the planet Desperus just happens to be sufficiently close to our heroes' flight from Kembel to Earth that they can be forced to land there.
    • This trope is averted in the episode "Amy's Choice". The TARDIS breaks down, and Rory asks why they can't just send a call for help; "Of course, because the universe is really just a small place, and somebody's sure to be near by," is the Doctor's snarky reply.
  • All five Star Trek series are guilty of this, though it's forgivable because, as stated here and at Sci-Fi Writers Have No Sense of Scale, a centuries-long journey between any two given inhabited places doesn't make a very interesting show. Anyway, many are the times something happens to a shuttlecraft. Not only is there almost always a planet nearby, it's almost always habitable enough for its occupants to survive for the time being.
    • This is subverted in ''Star Trek: Enterprise" when Reed and Trip are stranded in a shuttle that's running out of energy (needed to regenerate oxygen) and lacks a working warp (FTL) engine. Trip suggests that they may encounter another spacecraft or a planet, to which Reed responds that at impulse, they won't be encountering any planets until months after their energy runs out, and that an encounter with another spacecraft is very unlikely given the sheer size of interstellar space and the fact that they don't have working sensors or communications equipment.
    • In TOS, given the speeds at which starships are canonically stated to cruise, every planet in the galaxy is conveniently close. Kirk routinely flies the Enterprise away from the Planet of the Week at warp 1 (i.e. at, not faster than, the speed of light). Its maximum safe cruising speed is warp 6, which is either 216x the speed of light or 392x the speed of light depending on whom you talk to — but even assuming the faster of these two speeds, it should still take four days just to get from the Solar system to Alpha Centauri (our closest neighbor in interstellar space). Getting from Earth to the edge of the (8000 light-year-wide) Federation should take a decade. Instead, Star Fleet routinely sends them on assignments to the Neutral Zone and back home to Earth again in a matter of weeks or even just a few days.
      • It is never made clear however just how far away from Earth the Neutral Zone is. In fact, given that the Romulans are one of Earth's earliest enemies, it's likely that their territory isn't that far away at all. Further evidence for this is provided in ''Star Trek: Enterprise".
      • In spite of this, TOS presented the Neutral Zone and one of the few places distant enough from Earth that instant communication was not possible.
    • Also, the number of times they will just randomly encounter another ship, some space dwelling creature, or space/time phenomena truly staggers the mind. When you take into account the number that actually have threatened the galaxy, one wonders what happens when ships not staffed by Starfleet's best and brightest encounter such things.
    • At the end of Star Trek: Deep Space Nine's 'A Time to Stand', the crew are marooned without warp drive, 17 years from a Federation base. Nevertheless in the next episode, Rock and Shoals, they manage at short notice to hide in a conveniently close nebula where they find an uncharted planet.
  • Averted in Battlestar Galactica (Reimagined), particularly in season 1, episode 2, "Water."
    Tigh to Roslin: "The galaxy's a pretty barren and desolate place when you get right down to it."
    • In season one episode "Act of Contrition" Starbuck is incredibly lucky to have been right next to a planet when she had to punch out.
    • Although they did encounter a lot of planetsnote  in the series the "jump" method of travel obscured the distances; many of the hops were described as requiring several jumps.
    • At one point, a trio of Basestars discovered the blast of a nuclear warhead from a lightyear away - and warp over instantly to check it out.
    • The planets Caprica and Gemenon are part of a double-planet system, orbiting extremely close to each other (about the distance from Earth to the Moon). This makes their mutual views of each other rather spectacular.
  • Done all the time in the marionette series Fireball XL 5 where in spite of the titular spacecraft's inability to exceed the speed of light, it still managed to travel to a different planet (often in different star systems) nearly every episode.
  • Also done in the earlier marionette series, Space Patrol, although it's never completely clear whether or not their spaceship can travel at faster than light speeds.

  • The backglass for Orbitor 1 has three large astronomical bodies impossibly close to each other.
  • In Firepower, the alien warworld is so close to the Earth that humans can retaliate with their rocket-powered spaceships.

    Theme Parks 
  • It apparently only takes three or-so seconds of lightspeed to reach the Green Planet in E.T. Adventure.
  • Subverted in Mission: SPACE. It is a five minute simulator ride that takes you to Mars, but this is justified when the ride puts you into a pretend "hyper-sleep".

    Video Games 
  • Zig-Zagged in EVE Online, traveling from one planet, asteroid belt, or Stargate to another generally takes only a couple minutes. At warp speed.
  • Star Ocean The Last Hope involves the ship getting sucked into a "black hole" and conventiently being spat out directly over an alternate universe Earth.
  • Played a little crooked in Space Pirates and Zombies, where you travel from star-to-star and planet-to-planet in seconds. Granted, you use warp gates for both, but in planetary environments, you must first send out the warp gate to your destination before using it, which should take a while, but it doesn't. And it did take a while in the official story, so it's breaking its own rules. Then again, it is just a game.
  • Planets in Freelancer are close enough to each other that it takes mere minutes to travel between them in a one man ship. Trade lanes do little more than speed up a ship like an interplanetary highway, and the ships still move slow enough that they can be easily interrupted by pirates while traveling through a debris field. Completely bizarrely, planets are often listed as only a few dozen kilometers away and the ships and cross a kilometer in a few seconds even at a slow speed. Unless the game operates on a completely different system of units, the physics of the Freelancer universe are completely whacked out.
  • Freespace justifies it due to how FTL travel works in that series: FTL requires a gravity well, so you cannot jump into deep space. There has to be a star nearby (within roughly 100 AU's or so). Even interstellar jumps must begin and end in a star system. Intrasystem jumps take mere minutes at most, so no matter what, you're guaranteed to be minutes away from a planetnote ... assuming your FTL drive is working. If it isn't, you're kind of hosed.
  • Wing Commander Privateer features planets within a star system that never move, and are infrequently more than 100,000 meters from one another, and all are capable of supporting humans comfortably.
  • Invoked for laughs in Lego City Undercover. Chase has an incredibly short trip to the Moon, which Professor Kowalsky explains as the Moon actually being really small and very close to Earth. Apparently this is a secret that only scientists know.
  • Elite and its open-source remake Oolite sort of justify the trope by having your ship emerge from hyperspace at some sort of navigational beacon, and also by giving you a sort of hyperspace afterburner that propels your ship forward at much higher speeds than conventional drives should permit. The latter game does have a mod that makes the relative distances more realistic, but it's pretty dull.
  • Deliberately invoked AND Justified in Ratchet & Clank: Chairman Drek wants his new planet to be exactly where Veldin is.
  • In Star Fox 1, the planet Titania is visible as a large sphere from the low orbit of the planet Cornelia (Sector X).
  • In Anachronox, the party gets launched in some random direction when an Earth-Shattering Kaboom knocks the Sender Spike around while it's trying to launch them to Anachronox. 17 days of drifting at sublight speeds with no engines later, they run into the planet of Democratus. At least it's basically acknowledged since it took over 2 weeks, but on cosmic terms that's still conveniently close.
  • Averted in Kerbal Space Program. Even if distances are smaller than what the equivalent ones would be in reality, it's still a significant task to get to the Mun (analogous to the Moon). Just getting the right trajectory takes precise calculations (helped greatly by the in-game manoeuvre nodes you can use to plot courses), and without the time warp function (speeding time up to 100,000 times faster than real time) the game wouldn't be playable.
  • Luna=Luna from Meteos is a set two moons, both of which are similar to earth's moon, that are locked together in each other's orbits. The planet's profile image gives the sense that there isn't much distance separating the twin moons. The rocket-like natives even jump between both moons causally.
  • No Man's Sky's star systems have planets that are, with very few exceptions, incredibly close to one another. The resulting Scenery Porn and Alien Skies that result when someone is on those planets makes it acceptable.

    Web Original 
  • Avoided in the French MP3 saga "Adoprixtoxis". After leaving the planet about to be destroyed on an escape pod, the characters ask the spacecraft computer to search for close worlds to land. The computer retrieve only 1 hit: the planet they just left
  • The SCP Foundation finds SCP-1958, a nasty aversion to this. A group of space-travelling beatniks (It Makes Sense in Context) attempt to leave Earth for Alpha Centauri in a somehow space-worthy minibus, apparently believing that travelling at 80 mph the whole way would get you there in four weeks. They realize something's wrong when it takes them two months just to pass the moon. The severe vitamin deficiencies they were all suffering from by that point (their forward planning was somewhat lacking) may explain why they didn't turn around and go home.

    Western Animation 
  • In the very first episode of the original The Transformers series the Autobots leave Cybertron in a spacecraft with the Decepticons in pursuit. The Autobots are boarded and as the battle rages the spaceship plunges inexplicably down to Earth without going through any hyperdrive or seemly traveling far at all.
  • In Transformers: The Movie, all planets in the universe seem to be only a few minutes away from each other at sublight speeds.
  • The New Adventures of Superman episode "Rain of Iron". A villain fires iron balls out of a cannon in a specific direction. . They fly through space, hit an asteroid and bounce back to Earth at a specific location. Asteroids (a) aren't close enough to Earth for this to work and (b) travel in orbits around the Sun, so firing the balls in a specific direction would only work once.
  • Star Wars Expanded Universe in general is a pretty big (heh) offender, but Star Wars: The Clone Wars deserves a special mention: every time something goes wrong with a starship, it is able to land on a Conveniently Close Planet with breathable atmosphere in just a few minutes.
  • The Jetsons: George and Elroy's cub scouts go to the moon via spaceship which is just like a bus trip.

    Real Life 
  • If you take a look at the page image, think about how it took astronauts three days to travel from the Earth to the moon. If you added the sun to this scale - about 10 cm (ca. 4 inches) depending on your screen resolution - it's 38 meters (124 feet) away from where you're sitting and is about 35 cm (a foot) across. The dwarf planet Pluto is 1.235 km (0.77 miles) away, and the nearest star (Alpha Centauri at 4.3 light years IRL) is 10,473 km (6,508 miles) away. The speed of the Apollo would be roughly 1.4 milimeters per hour and the speed of the light approximately 280 meters per hour.
  • The crew of Apollo 13 (which you can watch in the movie Apollo 13) are probably the only humans to truly have a grasp of how terrifying it is in a crippled spacecraft to get back to a planet that's only 400,000 km away — a teeny hop in astronomical terms.
    • And it was actually easier for them, since Apollo 13 (and several other Apollo missions) had been launched in a free return trajectory, where if a mid-course correction is not done, the ship goes around the Moon and ends up back on Earth by gravity alone. They had already performed that mid-course burn, but were able to quickly do another burn (using the intact lunar module) to get back into a free return trajectory. Had they not been able to do that, they would have no way to get back, and would either crash into the moon or become another celestial object. And if the command module were not intact enough, they would burn up on reentry.
  • Planet Earth itself is rather lucky to have a conveniently close satellite in the form of the Moon. The surface area of the Moon is about one thirteenth that of the Earth. If and when Earth ever starts colonizing outer space, they will find the Moon to be large enough to be a world on its own, and far easier to reach than the other planets (let alone the stars, naturally). Sure, there's no air, water or life, but there's a decent gravitational field and lots of mineral resources. They don't know how common it is for an Earthlike planet to have a satellite like the Moon, but there's nothing quite like it in the rest of the solar system—Venus has no moons at all, and Mars' "moons" are far too small to be especially useful for colonizing space the way Earth's Moon probably will be. However Mars' satellites are still good for a very big space station protected from asteroids and radiation by kilometers of solid rock and low gravity is useful when you want to build a spaceport.
    • Jupiter's four major moons are all about the size of Earth's moon, and Titan, orbiting Saturn, is sufficiently large to retain an atmosphere. However, they are all much smaller than the parent planet.
  • Several probes have been sent out, some of which have entered interstellar space. How long will it take for them to reach the next star out on their path?
    • Voyager 1 (the fastest of all the probes below), is not heading towards any particular star, being sent out on a trajectory to examine the planets in our solar system, but in about 40,000 years it will pass within 1.6 light years of the star Gliese 445 in the constellation Camelopardalis (too bad it'll run out of power by 2025).
    • Voyager 2 is also not headed toward any particular star, for the same reason. Expected to enter interstellar space in 2016, if left alone, in roughly 40,000 years it should pass by the star Ross 248 (where "pass by" means "come within 1.7 light-years"). 256,000 years after that it will pass by the star Sirius at 4.3 light-years, which is still about as far as the sun is from Alpha Centauri, the nearest star to us besides our own sun.
    • Pioneer 10 is heading in the direction of the star Aldebaran in the constellation Taurus at roughly 2.6 AU per year. If Aldebaran stays put where it is (which it won't), it will take Pioneer 10 about 2 million years to reach it.
    • Pioneer 11 is headed toward the constellation of Aquila, northwest of the constellation of Sagittarius. Barring incident, Pioneer 11 will pass near the star Lambda (λ) Aquilae in about 4 million years time.
    • The New Horizons probe to Pluto was launched in 2006 and is the fastest spacecraft ever lobbed off the planetnote . It's going to take a mere nine years to get there, so hopefully it packed a lunch. In keeping with the trope in Real Life, the probe is going so fast that it will not be stopping at Pluto, as the amount of fuel and engines for braking to orbital speed would add considerable mass and therefore several years to an already long trip. The probe is doing the equivalent of a "drive by", shooting pictures as it passes. (Just think of how disappointed the probe will be when it gets there only to find out Pluto was demoted after it left....)
  • On 8 November 2011, the asteroid 2005 YU55 passed 324,900 kilometers (201,900 miles) near the Earth. This was incredibly convenient for the astronomy community, but even with the warning no spacefaring nation could scramble a mission to check it out up close, so astronomers had to settle for observation from a distance.
  • The planets of the Kepler-11 system or other compact planetary systems like 55 Cancri or Gliese 581 (the innermost ones in both cases). While in the best case if you were in one of them you'd see the other(s) like Terrans see the Moon from the Earth, in astronomical terms and with the technology usually available on sci-fi shows/novels they're quite close to each other.
    • The two confirmed planets in the Kepler-70 system are only about 240,000 km apart at their closest approach, which is closer than the Moon ever gets to Earth. And a third planet (KOI-55.03) is suspected to be orbiting between them.
  • Generally speaking in real spaceflight it's not good if you can see another spacecraft outside your window unless you are planning on docking with it. There is plenty of.. well... space in space so there's really no reason to risk a collision by flying close.
  • There can however be some truth to what most Sci-Fi writers put in their stories. In space, Stars are the only remotely close thing we have to a static point, which a navigation computer can use to steer the ship on the proper course. Once the ship is in a system, it would then use the planets to navigate, which would in turn, mean that a number of space battles would in fact occur 'near' a planet... Well... in the astronomical sense, at least.
  • Pointed out by CNN during the coverage of missing Malaysian Air 370 that some people have been saying "why can't they just have a satellite look?" and that satellites can't wander freely in the sky.