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"I can't slow down!"
—Crown, Mobile Suit Gundam.
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The process of atmospheric entry can be compared to hitting treacle after a ride across ice (or, if you're American, suddenly hitting a wall of peanut butter during an easy downhill jog). A fast-moving object compresses air before it, generating a lot of heat in the process. In fact, there are not many substances that can withstand the heat generated, and most spacecraft have an ablative heat shield that burns off during re-entry, which requires the spacecraft to come in at a fairly precise angle. This itself is a danger because if the craft comes in at too low an angle, it can literally bounce off the atmosphere and be lost in space, while if it comes in at too high an angle, no heat shield can save the craft from being destroyed.
One other side effect of this whole process is that the heat generated strips electrons from the atmosphere. Since radio waves can't penetrate the resulting cloud of plasma, the spacecraft's communications systems are rendered useless for the duration of the process, which lasts for several minutes. Well, it used to- see below.
Therefore, the situation will arise in Speculative Fiction when a spacecraft whose current ability (due to damage) to survive reentry is unclear does have to make an atmospheric entry. There may be a pre-announced time before communications are restored — it will pretty much never meet it. There will be a wait of a good thirty seconds or more, the ground crew will just be about ready to give up — then they will get a message from the crew, usually saying they are alright and coming in for a smooth landing.
See also Coming in Hot. Often followed by You Had Us Worried There. Contrast Frictionless Reentry.
Anime & Manga[]
- Mobile Suit Gundam Seed has one when, as the Archangel descends to Earth, Kira has to perform re-entry separately in his Humongous Mecha. The Strike is, fortunately, equipped to handle it, but between the physical strain and the Heroic BSOD he's just been kicked into, Kira spends the next episode or so in a coma.
- Of course, given that the series was rather closely aping the original Mobile Suit Gundam, a similar scene happened there, too. In the TV series, he had a special heat-deflecting coating he had to put on mid-reentry, while in the movie the Gundam survives by holding its riot shield in front of it and venting its entire supply of engine coolant into it. Amuro fares much better than Kira, however.
- And they both fared a whole lot better than poor Crown.
- In both cases the re-entry blackout could be justified despite taking place in the future due to the fact there's a space war going on. According to some UC sourcebooks, Earth's communications sattelites were one of the first things Zeon targetted. In SEED, the other side of the war has near total dominance in space and quite likely did something similar earlier in the war.
- For the hat trick, Crossbone Gundam does it as well. Kincade's Crossbone X-1 is badly damaged by Zabine's X-2, post-defection and knocked into the atmosphere. For three chapters it looks like he died, but he makes a grand return, revealing that he survived by using the Gundam's beam shields. Even so, he was very badly beaten up, but was recovered by the Federation, who treated his injuries including giving him a prosthetic hand.
- In Gundam Unicorn, it looks like Banagher will have to do this after acciedentally killing Gilboa, but in the next OVA we find out that the Garencieres collected the Unicorn in its own emergency descent to Earth.
- In the climactic episode of Super Dimension Fortress Macross, Hikaru blacks out during a dogfight and comes to while his mech is beginning its plunge through Earth's atmosphere. He averts disaster by ... um ... switching to his mech's F-14 fighter jet configuration, which I guess means heatshielding (?).
- In the Cowboy Bebop episode "Wild Horses", Spike has to deal with the possibility of burning up in the Earth atmosphere along with his Swordfish.
- Happens Twice in Rocket Girls. First time winds up with Yukari and Matsuri having to share a pod. Due to this Matsuri take the equivalent to being under 800 pounds due to Yukari having to sit on her during rentry and coming out perfectly fine. The second time happens when a calculation error lives Yukari and Akane stuck in orbit because their capsule can't take the temperature from reentry due to them being out too far. Akane and mission control figure out a way to get back using a Skip Jump method to bleed off momentium. However, Akane being an Ill Girl, she passes out and Yukari has to improvise.
- Happens in an early episode of Transformers Cybertron with Bud and Scattorshot.
- The Cyborg 009 manga originally ended with Joe and Jet implictly dying in this fashion when 002 tries to save 009 as he's falling back towards Earth, but burns up too much fuel reaching him. Shotaro Ishinomori eventually "lost to the tears of the fans" and Retconned in their survival, courtesy of Ivan reawakening and using his psychic powers to teleport them to safety.
- In Getter Robo Armageddon, the Shin Getter Robo is blasted from the approaching Jovian moon Europa back to Earth after a failed attempt to blow it up with Stoner Sunshine, they're unable to re-correct themselves as they reenter the atmosphere and they were assumed that the Getter Team were killed.
Comics[]
- Tintin. Happens in Explorers on the Moon as the "crushing G-Forces" make the crew black out every time (even when landing on and taking off from the Moon). Although the rocketship is designed to land automatically, it's still played up for tension with the usual comm failures and/or engine problems each time.
- Jean Grey of the X-Men first encountered the Phoenix Force while using her telekinesis to hold the damaged space shuttle she and her friends were in together through re-rentry.
Films[]
- Apollo 13
- And this actually happened in real life, too. See below.
- In The Right Stuff, John Glenn is bringing home the Friendship 7 capsule. There was concern that his heat shield had detached and that his craft would burn up on re-entry. In the movie he hums "The Battle Hymn of the Republic" during this stressful time, but he didn't in Real Life.
- In ~2010: The Year We Make Contact~, the technique of "aerobraking" is used to slow down the spacecraft Leonov approaching Jupiter at high speeds — they enter the outer atmosphere, which acts as a brake and bleeds off sufficient velocity for them to enter orbit. Although the ship in question is designed precisely to do this, the tension is played up, as a very slight miscalculation would indeed end up in fiery death or the ship "missing" its orbit and flying out into space, lost forever.
- In 2006, 20 years after the film was made, the Real Life Mars Reconnaisance Orbiter successfully used Aerobraking in the Martian atmosphere to bleed off some of its speed. It didn't do the harsh heat-shield-needing aerobraking that the Leonov did in the movie, however; it used conventional rockets to brake from interplanetary speed into a highly elliptical Martian orbit, then grazed Mars' outer atmosphere on three successive orbits to lower its apoapsis altitude (the far part of the ellipse).
- Space Cowboys
- Played for laughs in Serenity.
Mal: This is the Captain. We have a little problem with our entry sequence, so we may experience some slight turbulence and then... explode. |
- Also done in Space Camp (among other space-based scares), where a camper has to get the space shuttle angled just right for reentry, and has trouble doing so. And then Mission Control loses contact with the shuttle (as per reality) due to reentry, so it's a scare on two fronts.
Live Action TV[]
- Stargate Atlantis, on more than one occasion.
- Including once with the entire city-ship of Atlantis.
- A major plot point in The X-Files episode "Space", where a Space Shuttle has to make an emergency reentry due to a bad case of evil alien ghost.
- In the pilot episode of Salvage, after the astronauts are returning to the Earth from the Moon, they're unconscious (and thus unable to control their ship) as they enter the Earth's atmosphere. The government is going to shoot them down unless they can hear "voices", indicating that they're alive and able to land it safely.
- In the first episode of OUTCASTS, Carpathia Transporter 9 is on final approach. Despite repairs to the heat shield, the ship is fatally damaged on the already notoriously dangerous Carpathian entry. The communications go down just after entry, but return later on when the captain informs Forthaven that his ship will not survive. The sub-shuttles are released, and CT 9 breaks up.
Literature[]
- In the Red Mars Trilogy, a ship full of security troops is coming from Earth to Mars during the second Martian war for independence. The ship, going Too Fast to Stop, is relying on aerobreaking (decelerating through atmospheric friction). The Martians send up a missile loaded with scrap metal and detonate it in front of the ship moments before it hits the atmosphere, leading to a choice of: a) take a steeper reentry angle and burn up, b) get hit by the shrapnel, possibly holing their heat shield and burn up, or c) skip off the atmosphere and use another gravity well to turn around and go home.
- Double Subverted in Stationery Voyagers. Most of the worlds have just enough muellexic technology to not have to worry about heat. But when you're being chased by enemy vessels constantly trying to blow you apart from behind...
- Minshus, pulling off what no mere human being can do, somehow re-enters Mantith's atmosphere slowly enough not to worry about friction. If he weren't God, then there'd be a meterologist crying somewhere.
Video Games[]
- Can happen in Orbiter. Some ships are actually destroyed if you screw up re-entry (Although that depends on whether the person who created the ship included the necessary programming to do so).
Web Comics[]
- Happens in The Adventures of Dr. McNinja, where the titular Doctor, clad in a spacesuit, is riding a Dracula-imitation robot (with laser eyes) into Earth's atmosphere, after having jumped from the real Dracula's moon base using a technique taught to him by Bruce Lee. Yeah.
Western Animation[]
- The Simpsons had this in an earlier episode, when Homer was made an astronaut. During the tense re-entry, the two veteran astronauts stoically hum "The Battle Hymn of the Republic", while Homer nervously sings the "Golden Grahams" jingle.
- This is
likelyobviously a parody of John Glenn in The Right Stuff.
- This is
- In the final episode of Justice League, "Starcrossed (Part 3)", the Watchtower is Colony Dropped onto the baddies' base and almost burns up (Batman manages to barely avert it).
Real Life[]
- This used to be Truth in Television, but they've fixed the problem.
- The trick being to send the radio waves up, since the communications aren't blocked in that direction. A satellite picks the signal and retransmits it to ground.
- The blackout during the re-entry of Apollo 13 really was one and a half minutes longer than anticipated. According to mission controller Gene Kranz it was the the "Toughest minute and a half we ever had." The Houston controllers didn't start cheering as soon as they re-established radio contact though. They saved that until Lovell reported that they were floating, right side up, in the Pacific Ocean.
- The reason the radio blackout lasted longer than usual was that the Apollo 13 Command Module hit the atmosphere at the shallowest re-entry angle EVAR, nearly at the lowermost limit before they would have ricocheted back off into space. This happened because a steam vent on the Lunar Module had been applying a very weak thrust to the docked spacecraft on its way back to Earth, without anyone's knowledge.
- Tragically inverted on the last flight of the space shuttle Columbia. The heat-shielding tiles had sustained damage during the launch, but the crew wasn't aware of it.
- More specifically, right on the wing's leading edge root. When the tiles failed, the structure of the wing was subjected to extreme heat, and the connection between the hull and wing failed, ripping the wing off. Without a wing, the shuttle couldn't maintain the correct orientation to come down safely, flipping upside down halfway through. The computer tried to reorient the spacecraft, but it was a lost cause. The bottom part is the most heavily heat-shielded on the shuttle, and now they were plummeting with the most vulnerable part of the shuttle pointed right into the heat - there was no way to survive after that, and the shuttle disintegrated completely. Just before the clock struck 9, all contact was lost. It was twelve minutes of terse silence broken by intermittent requests for the shuttle to come in before they realized the shuttle was destroyed.
- A number of chilling eyewitness reports (from people who were in the flight path and had gone out to watch the overflight) noted seeing the beautiful streak of the shuttle passing overhead before looking more closely and noticing that it was, in fact, several streaks.
- More specifically, right on the wing's leading edge root. When the tiles failed, the structure of the wing was subjected to extreme heat, and the connection between the hull and wing failed, ripping the wing off. Without a wing, the shuttle couldn't maintain the correct orientation to come down safely, flipping upside down halfway through. The computer tried to reorient the spacecraft, but it was a lost cause. The bottom part is the most heavily heat-shielded on the shuttle, and now they were plummeting with the most vulnerable part of the shuttle pointed right into the heat - there was no way to survive after that, and the shuttle disintegrated completely. Just before the clock struck 9, all contact was lost. It was twelve minutes of terse silence broken by intermittent requests for the shuttle to come in before they realized the shuttle was destroyed.
- John Glenn's Mercury flight had a tense re-entry when mission control got an indication that the heat shield had detached. They attempted a re-entry with the retro-rocket pack (which covers the heat shield) still in place (it would normally be jettisoned before entry) in the hope it would hold the heat shield in place just long enough to do its job. In the end it turned out to have been a false indication and the heat shield had remained firmly attached to the craft.
- One account says that this gave Glenn another scare, since he was under the impression that the pack had been detached as usual. So when molten chunks started flying past his window, he thought it was his heat shield coming apart...
- The last flight of the Mercury program, with Gordo Cooper at the controls, suffered a failure of nearly every system on board during orbit. Cooper had to perform the deorbit burn and upper-atmosphere steering manually, with only the horizon out his window for reference and his wristwatch for timing. Not only did he succeed in splashing down safely, he landed closer to the recovery ship than any previous astronaut.
- Soyuz TMA-10 and TMA-11 both suffered from a "ballistic re-entry", an entry trajectory steeper than normal, exposing the crew to high G forces and a very rough ride. Both incidents had a happy outcome and the crews were recovered none the worse for wear.
- Ballistic reentry is in fact the normal reentry mode for Soyuz capsules, it's just not normally used because of the excess stress it puts on the crew. Soyuz's heat shield is massively over-engineered so it can withstand most conceivable reentry angles.
- Soyuz 1 suffered a huge number of malfunctions during its ill-fated mission, culminating in the failure of the landing retros and parachutes intended to slow the capsule's impact with the ground to something survivable. Rumour has it that the sole crew member's last radio transmission consisted of him cursing the engineers to Hell as he plummeted to his death.
- It's more than just a rumour now that the tapes have been released.
- What made this disaster all the more tragic was that even while still in orbit, the ground controllers were convinced the malfunctioning spacecraft couldn't make a successful re-entry. Komarov's wife was brought into mission control to say her last goodbyes, but the cosmonaut only assured her that he wasn't about to die just yet. Just like Gordo Cooper, he fought the controls and managed to hit his re-entry corridor squarely — and then, just when he thought the worst was over, his parachutes failed to open.
- It happened to be a design flaw — when during the investigation the next capsule in the series (which was discussed as a possible lifeboat for Komarov at one time) was tested closer then before, they couldn't force it to release its 'chute with the winch. It was a height of the Moon Race and Soyuz was designed and tested in enormous haste and under tremendous pressure, so a lot of normal tests and safety measures were skipped.
- Everybody on the ground knew that Soyuz was unready to fly, but the pressure to launch was coming from the utmost heights, so no one could really insist. Yuri Gagarin, then a commander of the cosmonaut corps and Komarov's best friend, tried to install himself as a Soyuz-1 pilot, considering that the authorities wouldn't risk the first man in space, but was unsuccessful.
- The crew of Soyuz 11 died during re-entry when a valve that was supposed to seal the lines between the crew module and the jettisoned service module failed, causing a gradual decompression of the cabin.
- Vostok 1 suffered a failure to fully separate from its service module prior to re-entry, causing the spacecraft to enter at a squirrelly angle that potentially could have ended in disaster.
- During the early spaceflight years the explosive bolts and cable cutters were far from being a mature technology[1], so the Soviet engineers decided to err on the side of a caution, but unfortunately did it a bit too well. Early Soviet pyro devices (cable cutters in particular) turned out to be a bit underpowered, and a failure to cleanly severe a service module from the reentry capsule became something of an endemic bug, persisting well into the Soyuz run. Luckily the cables are usually the very first things to burn up during the reentry, so no real accidents happened due to them, but there's been a few harrowing near misses.
- Soyuz 5 also failed to separate from its service module and was in fact still attached to it at re-entry, leading to a harrowing couple of minutes when the crew module was entering hatch first! Fortunately the service module gave way before the hatch melted and the unencumbered space craft turned itself heat shield first in the nick of time.
- The heat shield of Soyuz incorporates a 60 kilo lead weight precisely for that purpose, so the capsule center of mass would be shifted to its bottom and aerodynamic forces on reentry would orient it into the correct attitude regardless of the capsule and the pilot state. It also serves as a heat absorber, allowing for the much steeper reentry angles without the shield melting on the way.
- ↑ Remember the tragic fate of Gus Grissom, who nearly drowned after the hatch of his Mercury capsule jettisoned prematurely, and thus insisted on removing the explosive bolts from the Apollo-1 door--preventing him and his crewmates from escaping when the interior of the capsule caught fire.