Glossary

Every word the manual uses that a new player might not know, one line each. A term used on a page and missing here is a bug: say so.

A to D

Heat tiles: A strip of ceramic bolted down a ship’s flank that shields whatever it lies over and is never used up. It only works broad side into the airstream, which is what its Hold into wind action is for. See Air, heat and speed.
Ablator: The layer a heat shield burns away as it takes the heat of re-entry. The card shows how much is left.
About list: The rows at the bottom of Settings naming the build you run and whether it is connected, and the address to write to us.
Achievement: A feat the game notices and pays for in credits and discovery, once. Some are hidden until you earn them.
Administration: The Space Center building where companies offer contracts. Its level is how many you can hold at once, and how hard they get.
Advance: The credits a contract pays the moment you accept it. You owe it back, with a tenth on top, if the job is never finished.
Aerobrake: Slowing a ship by flying it through a world's air instead of spending fuel on the engine. Only worlds with an atmosphere allow it.
Aeroplane: A ship that flies on wings in Earth's air, pulled by a propeller and standing on landing gear. It takes off from the runway. See Aeroplanes.
AGL: Above ground level: the height over the ground or water right under the ship. Tap the altitude reading in flight to show it in place of ALT, the height above sea level.
Air intake: The open nose a jet breathes through. A jet makes no thrust without one, and too small a one starves it. See AI-1 Air Intake.
Airless world: A world with no atmosphere at all: nothing to slow a descent, nothing to heat a hull, and nothing to climb through. Nineteen of the 28 worlds and moons are airless.
Antenna: A part that carries your commands to an uncrewed ship. Its card gives a rating, a role and a draw.
Antimatter: What an Antimatter Converter makes out of helium-3, counted in micrograms. It is never bought: every container launches empty. Only an Antimatter Container holds it, only in space, and only while powered. See Helium-3 and antimatter.
Antimatter Container: The magnetic trap that holds antimatter, the AM-4 or the AM-8. It launches empty and holds in space alone, for a power draw set by its gravity gauge. Landed or in air with a load aboard, it explodes a minute later unless vented. See Keep antimatter safe.
Antimatter Converter: The orbital factory that turns helium-3 into antimatter, 437 g to the microgram, only in space. See Make antimatter.
Antimatter Reactor: The plant that burns antimatter for electricity where there is no sunlight. It needs a nuclear scientist aboard and radiators to shed its heat. See Reactors and heat.
Apoapsis: The highest point of an orbit, and the map marker AP. Burning here lifts the periapsis.
Ascent: The powered climb from the pad to the top of the air, before any coasting.
Asparagus staging: Side boosters piped into the core with fuel lines: they keep the core full while every engine burns, drop away empty, and the core leaves full. See Empty the side tanks first.
Aspect ratio: A wing's span divided by its chord. A long, thin wing has a high one and pays less drag for its lift.
Astronaut: A Meek who can fly a pod. Every pod needs one aboard before the rocket may fly.
Astronaut Center: The Space Center building where the Meek are recruited. Its level is how many you can keep.
Attachment point: A place on a part where another part joins: the top or bottom of a stack, a point on a flank, or a face a wing sits on.
Attitude: Which way the ship is pointing, which is not the same as the way it is moving. The navball shows it.
Autobrake: A landing gear switch, on by default, that holds the wheels' brakes whenever the throttle is at zero and lets go when it opens.
Autoburn: A planned burn the world flies for you at its time, exactly as planned, while you are away from the ship: FLY IT FOR ME on a node's panel. Paid in gems when you mark it, and given back if it is not flown. See Let the world fly a burn.
Barometer: The instrument that reads air pressure in kilopascals, and zero above the air.
Battery: A part that holds electricity and nothing else. Its charge reaches every part on the ship.
Beam: A part that is bare frame: it carries nothing and does nothing, and exists to hold other parts apart. Both beams stretch, and both flanks are a rail. See Parts: Beams.
Biome: One band of a world's surface, with its own colour, its own typical height and its own kind of ground. A reading names the biome it was taken over, and every world's page lists all of its own.
Blackout: A Meek passing out under sustained load, or under a spin. The pilot's blackout kills the ship's controls until they come to.
Burn rate: How fast a solid booster's grain was cast to leave its throat, 50 to 150 % on its hangar sheet. It scales the thrust and the burn together, so a slower cast pushes less for longer out of the same case. See Solid boosters.
Canopy: The open dome of a parachute. It opens over a second, drags the ship, and collapses at touchdown or when you cut it. The canister stays on the ship either way, spent until an engineer repacks it.
Cargo Bay: A stretchable hold you load in the hangar with any resource, each packed at its own rate. See Load a cargo bay.
Capture burn: The burn that turns a fly-past into an orbit once you are inside a world's sphere of influence. Without it you cross the sphere and leave again.
Centre of lift: The point the air's lift acts through. The hangar draws it as the green arrow.
Centre of mass: The point the ship balances on. The hangar draws it as the black and yellow disc; thrust that misses it turns the ship.
Chapter: One run of Programme missions on a theme, from Off the Ground to Further Out. A Programme card names its chapter and how far through it you are.
Chord: How deep a wing is from its front edge to its back edge: the length the side view shows. Set with a wing's Chord slider.
Charge gauge: The lit slot on a battery's casing that empties as its charge goes, amber under a quarter and red under a tenth.
Circularise: To burn at apoapsis until the periapsis rises to meet it, leaving a round orbit rather than a long ellipse.
Cloak: What a ship of yours wears once you pay gems for it on its pod or probe core: no other player ever sees, meets or touches it again, and nothing of theirs is solid to it. Kept for good, on that ship only. See Cloak a ship.
Client: The company whose name is on a contract. It pays the advance and the reward; the name is flavour and nothing else.
Closest approach: The nearest your forecast path comes to the target ship over the next lap of your orbit, marked CLOSEST on the map.
Cloud band: What a gas giant has instead of a biome: a named belt of cloud round the world. Nothing lands in one, since there is no ground under it.
Coast: Flying with the engines off. It costs nothing and changes nothing about the path.
Comm Station: The Space Center building that is the ground end of every radio link: one dish, on Earth, for your whole game. Its level is its reach.
Comms chip: The map chip that draws the radio links, cycling through off, CHAIN and NETWORK each time you tap it.
Contract: A paid job from a company: meet its goals in one flight before its deadline for the reward, or pay the advance back.
Contract board: The list of contracts on offer and under way, opened from the Administration with Open contracts.
Contract tier: How demanding a contract is, 1 to 3. The Administration's level decides which tiers reach your board.
Cost: A rocket's price, every part's cost added up. It is what a launch charges.
Credits: The money. Launches, buildings and crew cost credits; achievements, contracts and recovery pay them.
Crew module: Any part with seats in it: a pod, which has the controls too, or a Passenger Cabin, which does not. A ship with two of them can move people between them in flight.
Crew chip: The panel at the top left of the flight screen: who is aboard, what state they are in, and the days of food left. Tapping it opens the crew sheet, the same crew with their portraits large.
Datum: The level a world's heights are measured from. A landing says how far above or below it the ship came to rest.
Deadline: The real-world time you have to finish a contract, counted from the moment you accept it. It runs while the game is closed.
Decoupler: The coupler that drops a booster off the flank. It is destroyed when it fires, so it goes with neither the booster nor the rocket.
Deploy: Swing a folded panel or dish out of its housing. Deployed, it works and it is fragile; stowed, it is neither.
Deposit: A point of interest with helium-3 in its ground. Once you have found it, it stays on the map in mint and a Mining Rig landed inside it can work it.
Discovery: The second currency. It buys tech nodes and nothing else. Achievements pay it, including the ones a reading earns, and so does every mission of the Programme; an ordinary contract pays credits only.
Dish: An antenna that rides up folded and swings out on a boom. Worth nothing to the network until it is deployed.
Dock: To bring two docking ports together slowly and squarely enough for the latches to close, joining two ships into one.
Docking mode: The third position of the flight screen's thumb-pad switch (DOCK): the turn keys and the sliding keys on screen at once in one band along the bottom, with the throttle, stage button and RCS switch taken off the screen. See Flying.
Docking Port: The latching ring two ships join through. It accepts nothing but another docking port, and every resource crosses the joint once it is made.
Control from here: The switch on a command pod that says you are flying from that one. It decides who steers, which way the navball points, whose astronaut is the pilot, which pod has to have an astronaut in it at all, and which half you stay with when a ship comes apart. Only one pod on a ship holds it. See Rendezvous and docking.
Dormant ship: A ship of yours out in the world with nobody flying it. It keeps its path and waits on the map.
Drag: The air pushing back on a moving ship. The hangar draws it as the blue arrow.
Drawer: The column of parts that opens beside the palette's category tabs when you tap one.
Drogue: A small parachute that opens safely at high speed to slow a ship for the main canopy.
Dry mass: What a ship or a stage weighs with every tank empty. What is left to carry once the fuel is spent.
Dwarf planet: A small world that goes round the Sun rather than round a planet. Three of them do: Schmeckle, Flurbo and Pluto.

E to M

Eccentricity: How stretched an orbit is, on the map as ECC. 0.000 is a circle; bigger is longer and thinner.
Ejection burn: The burn that throws a ship out of the world it is orbiting and into a fall around the Sun. It is most of the cost of any trip between planets.
Electricity: The resource that runs pods, wheels, antennas and instruments. It weighs nothing and runs along every joint.
Elevator: The hinged back edge of an aeroplane tail's stabiliser. The pitch buttons swing it while you hold them, and it springs back to its trim when you let go.
Encounter: The point where your path comes nearest a target ship, marked ENC on the map.
Engine: A part that burns fuel for thrust. Its push depends on the air around it: less at sea level, more in vacuum.
Escape: Leaving a world's pull for good. The map says ESCAPE where an orbit no longer closes.
Escape speed: How fast a ship must be going, at a world's surface, to leave it altogether. Every world's page states it.
Fairing: A shell over the nose of a rocket. What fits inside it takes no drag and no heating, and the shell is split off once the air is thin.
Feat: Something a flight reached that a Meek's card records: leaving the pad, reaching space, an orbit, a landing on the Moon or Mars.
Fleet: Every ship you have left out there, parked or in orbit, all of them shown on the map.
Flight termination: Destroying a rocket, or part of one, on command. The FTS Charge does it: fired, it waits out a one-second fuse, then blows up and takes every part it is bolted to with it. See the FTS Charge.
Flaps: Panels on a wing's back edge that give more lift at low speed for much more drag. For take-off and landing.
Food: The crew's rations. One filled seat eats one seat's worth a day, out of any larder aboard.
Free fall: Moving under gravity alone, with nothing pushing. An orbiting ship is in free fall the whole time.
Freight: Transport work with nobody aboard: a client's package flown somewhere and brought back. The only kind of carrying work at tier 1.
Fuel line: A one-way pipe you draw in the hangar from one part to another. Into a tank it keeps that tank filled; into an engine it feeds it, even past a beam; beside a decoupler it decides which way fuel flows. Shown only in the hangar. See Draw a fuel line.
G: How hard acceleration presses on the ship and its crew, as multiples of Earth's gravity. Every part and every Meek has a limit.
G-tolerance: The stat that says how much sustained load a Meek stays awake through: 4 G plus 0.6 G a point. It also sets their spin limit, about 19 rpm at the bottom of the scale and 34 at the top.
Gas giant: A world with no solid ground under its air. There are four, and what you go to them for is their moons.
Gems: The third balance on the purse: 100 to every new player, the rest bought in packs in the Store, all spent on what credits cannot buy. Kept for good, through a reset too (which adds none), and never passed between players. See Credits, discovery and gems.
Geostationary orbit: Earth’s stationary orbit: a circle 2.87 Mm up where a ship keeps pace with the turning ground. See Stationary orbits.
Gimbal: An engine swinging its bell to steer. Most engines have a few degrees of it.
Give up: Dropping a contract under way for the same bill as missing its deadline. The button on the row arms first and sends on the second tap.
Goal: One condition a contract asks your ship to meet. Every goal on a contract must be met in the same flight.
Grade: A deposit's richness, written ×1 or ×1.5 beside its name on the map. It multiplies what a Mining Rig makes there.
Grappling Claw: Jaws that close on any part of another ship of yours in orbit, port or no port (never on another player's), and join the two into one ship until you release them.
Gravity gauge: The four lamps and the sheet line on an Antimatter Container that read how strong gravity is around the ship. One more on the gauge is ten times the pull, and one more helping of upkeep.
Gravity turn: Tipping a climbing rocket over early so gravity swings it toward the horizon, which is how orbit is reached cheaply.
Greenhouse: A glass module that grows food from the crew's waste, a crop at a time, while a botanist is aboard the ship, it is open, and its grow lights never lose power. Closed, its shutters make it tough enough to launch and it grows nothing. See Grow food in orbit.
Grid fin: A lattice fin that rides up folded flat against a booster, out of the air, and swings out on the way down to hold it engines-first and steer it. See GF-1 Grid Fin.
Ground Imager: A camera part that finds points of interest from orbit, with no contract or landing, while the ship sits in its imaging band, has charge and can be heard over the radio. See Image points of interest from orbit.
Ground station: The Comm Station's dish, standing on Earth and turning with the planet. Every radio link ends there, and there is only the one.
Grow lights: What a greenhouse spends its power on. A crop needs them lit for its whole growing time; one moment without power loses it.
Botanist: The trade that grows food. One botanist anywhere aboard a ship works every greenhouse on it; a second and third raise every harvest; with none aboard nothing grows. See Grow food in orbit.
Half-shell: One of the two halves a fairing splits into when it is jettisoned. Each is flown, not deleted, and breaks when it lands.
H/S: Horizontal speed, beside the navball: how fast the ship is travelling across the surface. Orbit is made of this one.
Hangar: The screen where a rocket is built and saved, and where Fly lives.
Heat shield: A blunt plate of ablator mounted under a pod to take the heat of re-entry.
Helium-3: A gas mined on the Moon by a Mining Rig, a few kilograms a day, and the only thing antimatter is made from. Every store of it launches empty.
Hidden achievement: An achievement the game does not describe until you earn one. The sheet counts them into a single row and says nothing else.
Hop: One link in the chain between your ship and a ground station. The radio chip counts them.
Hypergolic: The propellant thruster blocks and the Escape Motor burn. It runs along every joint on the ship and never mixes with fuel.
Imaging band: The height a Ground Imager works at: one world radius above the ground, give or take five per cent. Over Earth, 570 to 630 km.
Impact speed: The speed a part survives when it is the part that meets the ground, on its card as IMPACT.
Info card: The card that opens on a long press of a palette part, listing everything about it.
Instrument: A Thermometer, a Barometer or a Mass Spectrometer: a part that takes one reading each time it is tapped or staged.
Ion engine: An engine that fires xenon off a charged grid: about ten times as efficient as any chemical engine, with a tiny push, and it runs only while the ship has power. See Parts: Engines.
Isp: How far a kilogram of fuel takes you: the engine's efficiency, in seconds, quoted sea level to vacuum.
Jet: An aeroplane engine that burns methane in air it swallows through an intake, and keeps its thrust at speed: what takes an aeroplane through the sound barrier. See Aeroplanes: jets.
Jettison: To split a fairing off the rocket, either by tapping it or by staging it.
Lamp: A light bolted to a hull: the SL-1 Signal Light, red or green and able to blink, or the FL-30 Floodlight's white beam. It lifts the night off whatever its light falls on, and draws power while it is on. See Night, lamps and shadows.
Landform: A named piece of ground on Earth, the Moon or Mars: a range, a plateau, a valley, a crater, a volcano or a field of dunes. Some achievements ask for one by kind.
Landing gear: A wheel on a sprung strut that rolls along the ground and brakes. Any ship standing on it takes off from the runway.
Launch Pad: The Space Center building rockets start from. There is one, on Earth, and its level caps how heavy and how tall a rocket may be.
Launch site: Where a rocket takes off from. There is one: the Launch Pad on Earth, with its runway. Every other world can be reached and landed on, never launched from.
Lead: How far ahead of the moment a reminder speaks, from as it happens to a day early.
Lift: The sideways force air makes on fins and wings. The hangar draws it as the green arrow.
L/D (lift-to-drag): How much lift a wing gives for each unit of drag it costs. A wing's card shows its BEST L/D, reached flying a couple of degrees nose-up; pull harder and it falls.
Link: The radio path from a ground station to an uncrewed ship. Lose it and every control on that ship goes dead.
Locked part: A part put out of reach in the hangar with its lock button: taps go through it to what it covers, and the padlock drawn on it unlocks it. See Lock a part.
Mach number: A speed over the speed of sound in the air around the ship: Mach 1 is the speed of sound, Mach 2 twice it. The speed of sound falls as the air cools with height.
Maneuver node: A planned burn placed on your orbit on the map. Its handles set the push; the planned path shows where it takes you.
Map: The screen that shows worlds, orbits and every ship of yours, in flight and from the hangar.
Mass: How much the rocket weighs with every tank full, in tonnes. The Launch Pad caps it.
Mass Spectrometer: The instrument that reads what the air is made of: the mean molar mass of the mix in grams per mole, with the biggest gases named beside it.
Max temp: The temperature a part comes apart at, on its info card. A part glows before it reaches it.
Memorial: The Lost tab at the Astronaut Center: every Meek you lost, with how and where.
Mining Rig: The part that makes helium-3 while it stands, powered and switched on, on a deposit you have found: the MR-4 on the 4 m stack, the MR-8 on the 8 m one. See Mine helium-3.
Mirror: Flipping a part to the other side of the rocket. Two mirrored parts are linked, and moving one moves the other.
Moon: A world that orbits another world rather than the Sun. There are seventeen, and its sphere of influence sits inside its planet's.

N to R

Navball: The round instrument at the bottom of the flight screen: which way the nose points, the horizon, and the ship's speed.
Nerve: The stat that sets what a candidate signs for. A braver Meek is cheaper to hire.
Node card: The panel along the bottom of the tech tree for the node you tapped: what it sells, its tier, what it needs and the button that buys it.
Nuclear scientist: The Meek trade an Antimatter Reactor will not run without. One alive anywhere aboard is enough, and no other trade will do.
Occlusion: A world's solid body sitting across a radio path and blocking it. The commonest reason a probe goes quiet.
Offer: A contract on the board that you have not signed. It has its own countdown, and letting it expire costs nothing.
Orbit: The closed path a ship coasts on around a world. It repeats itself exactly until a burn changes it.
Market fee: 5% of a priced load's value, paid by the player who asks for the transfer, on top of the price. It goes to nobody.
Pad cap: The heaviest and tallest ship the Launch Pad accepts at its current level. Over either and the pad refuses the flight. On the runway the same two caps hold, the height read as the ship's length lying down.
Palette: The column of category tabs on the hangar's left edge. Tap one to open its drawer of parts.
Part sheet: The sheet that opens when you tap a part in flight: its actions, and the settings you may change in the air.
Passenger: A Meek handed to you by a tourist run, or by another pilot's contract to carry them. Free, outside the Astronaut Center's roster, never at the controls, and gone when the contract ends.
Payload: Whatever the rocket is carrying for its own sake: a satellite, an instrument, a lander.
Payload Bay: A hollow hull with clamshell doors. Cargo on its inner rails rides out of the airflow, and the doors open in flight.
Penalty: What an unfinished contract costs: the advance back plus a tenth of it, whether the deadline ran out, you gave up, or a passenger was lost on the way.
Periapsis: The lowest point of an orbit, and the map marker PE. Below a world's air, the orbit does not last.
Period: How long one full lap of an orbit takes, on the map as PERIOD.
Piece: What a dropped stage or a broken-off part becomes: a ship with nobody at the controls, still flying.
Piloting: The stat that says how hard the ship turns for the Meek at the controls.
Place: A world, a band of altitude, and — on the ground — the biome under you. What a reading is filed under and paid for.
Player contract: A job on the board every pilot shares, opened from the Administration at level 2: carry the parts it asks for into its orbit band, land them at its place or dock them to its ship, and DELIVER the ship for the reward. See Player contracts.
Destroy contract: A player contract to destroy a ship: any ship of yours rams it until it breaks up, and you are paid the moment yours destroys it, with nothing to deliver. You cannot post one. See Destroying a ship.
Race: A destroy contract several pilots may hold at once: the first to destroy its ship is paid, and everyone else gets their penalty back. See Destroying a ship.
Account: The Google, Apple or email sign-in your space program is kept under on the shared world. Sign in on another phone and your game follows; a code from the Account section of Settings brings it to a phone signed in with a different account.
Code: Six characters, generated under Account in Settings on the device that has your program, good for one minute and one use: typed on another device, its sign-in opens your program from then on.
Pod: A part with a seat and the controls in it. A rocket needs one, and the pod it is flown from needs an astronaut; a second one along for the ride counts as a cabin.
Point of interest: A named place on a world with a radius of ground around it. The first ship of yours to land inside it earns its reward, contract or not. Its survey contract, dealt once you have landed on that world, marks it on the map, and a low pass over a wide point counts only under a contract.
Poster's record: What a player contract's card says about whoever posted it, in place of a name: how many contracts they posted, paid and cancelled.
Prograde: The way the ship is moving; the navball's ⊙ mark. Burning prograde raises the far side of the orbit.
Programme: The ordered chain of 66 missions in 10 chapters at the top of the contract board: what to fly next. No deadline, no advance, no penalty, and any mission may be skipped.
Propellant: Anything an engine or a thruster throws out of a nozzle: oxygen and methane, solid fuel, hypergolic, xenon.
Propeller: A spinning blade that pulls an aeroplane through the air. It burns methane with oxygen from the air, so it runs only in Earth's air, and pulls less the faster you fly.
Properties sheet: The sheet that opens when you tap a part in the hangar that is already selected: its settings, such as a tank's length.
Prospect contract: The survey contract of a helium-3 deposit, titled Prospect: on the board. Landing inside the field completes it and finds the deposit; landing there without it finds the deposit alone.
Purse: The chip at the top left of the hangar, and in the header of every screen where you pay, with all your balances in one place: credits large on top, discovery and gems under them. Tap it in the hangar for the Your purse sheet: each currency, what it buys and where it comes from, and the way to Achievements and Readings.
Radiator: A fin of hot metal that folds out of its housing and throws the ship's waste heat into the sky. It only sheds into a sky colder than the fluid in its pipes. See Reactors and heat.
Radio chip: The top-left chip on an uncrewed flight: LINK and the hop count, the signal strength, or NO LINK and why.
Rail: A radial attachment point that is a line down a part's flank rather than a single spot — a fuel tank's side, a beam's. A part dropped against one stays at the height you let it go.
Range: An antenna's own rating, not how far it reaches. Two aerials reach the square root of their two ratings multiplied.
RCS: The thruster blocks that turn a ship or slide it sideways on hypergolic propellant, switched with the RCS button. They overheat after five seconds of firing flat out.
Reaction wheel: A spinning wheel that turns the ship without fuel, anywhere, on electricity: a small one inside every pod, and many times stronger in the RW-100 and RW-500 that sit in the stack.
Reading: One measurement by an instrument in flight, filed with where and when it was taken.
Readings log: Every reading you have taken, newest first, opened from the Your purse sheet in the hangar.
Readout: The strip along the top of the hangar: the rocket's mass, TWR and cost.
Recovery: Bringing a landed rocket home from the flight menu. Every part still aboard is refunded and the flight ends.
Recruit board: The Recruit tab at the Astronaut Center: seven candidates at a time, each with a price, each replaced when their offer runs out.
Client: A ship whose commands are passing through one of your relays. Every client costs that relay power, and it carries only as many as its Clients carried setting — and its batteries — allow.
Relay: An antenna that carries other ships' commands as well as its own. Only the CR parts do it.
Reminder: An alarm set on a map point or a node that reaches your phone when the moment comes, even with the game closed.
Rendezvous: Bringing two ships to the same place in orbit at the same speed, close enough to dock.
Repack: Folding a spent parachute back into its canister so it can be used again. Only an engineer aboard can do it, from the part's sheet in flight.
Requires: The list on a node card of everything that must come first, each with a tick or a cross: the nodes above it, and on two nodes an achievement.
Rescue: The Fresh Start Grant: a card at the top of the contract board while your credits are under 1,000. Signing it tops you up to 1,000 and is never taken back; at most once every 48 hours.
Research contract: A contract that pays discovery as well as credits for a reading a company names, and always comes back to the board.
Research Centre: The Space Center building that opens the tech tree. Its level is which tiers of the tree you may buy from.
Resource: Anything a ship carries by the unit and spends: fuel, hypergolic, xenon, electricity, food, ablator.
Retrograde: Against the way the ship is moving; the navball's ⊗ mark. Burning retrograde lowers the far side of the orbit.
Reward: What a contract pays when its last goal is met: the figure its offer quoted, in credits, and in discovery for research work.
Reward pending: The note on an achievement earned with no connection. The feat is yours; the credits and discovery arrive when the game reaches your account.
Ring: One of the hoops a fairing's skin is stretched over. Each has a slider, and widening one bulges the shell there.
Roster: The Meek you have hired and still hold. Your Astronaut Center's level is how many fit on it.
Rotate: Lifting an aeroplane's nose on the take-off roll, at flying speed, so the wing meets the air at an angle and lifts it off.
RTG: A radioisotope generator: a small sealed part that makes a trickle of electricity day and night, with no sun and nothing to deploy. See the RTG-1.
Runway: The strip of flat ground beside the Launch Pad, east of the tower, where a ship on landing gear starts. Its length grows with the pad's level.

S to Z

Sandbox: A world of your own, switched on in Settings, with its own clock, time warp and saved worlds. Nothing done there is spent or earned on your account; it keeps only its own achievements and crew, on this phone.
Sat Controller: The command part that flies a ship with nobody aboard, on its own reaction wheel and a small built-in aerial.
Science bonus: The extra a scientist aboard adds to a reading achievement: 10 % more credits and discovery per point of their science.
Scientist: The Meek trade that makes readings pay more. Only this trade pays it, whatever another Meek's science says.
Seat: One place for a Meek in a pod or cabin, filled on the part's Crew row in the hangar.
Separation Motor: A one-second solid rocket bolted to a booster's flank, fired as the booster lets go so the spent case is thrown clear of the ship.
Separator: The coupler that cuts a stack in line. Both its faces let go, and it blows itself clear rather than tumbling along behind.
Shared world: The one solar system every player flies in, on one real clock that no player can stop or speed up.
Ship library: The rockets you saved from the hangar, kept under your account and there on any phone.
Site: One instrument at one place. What the survey ticks off, so a Barometer earns where a Thermometer already has, and a Mass Spectrometer after both.
Situation: Which band of altitude a reading was taken in: on the ground, low or high in the air, low or high space. Part of a place.
Skip: Passing over a Programme mission for good, for nothing. Whatever was waiting behind it opens anyway, so the chain can never leave you stuck.
Small mine: The 4 m helium-3 chain sold on tier 3 — the MR-4 rig, the H3-4 tank, the AC-4 converter and the AM-4 trap — which makes a probe's antimatter before any warp drive is on sale. See Two sizes of mine.
Solar panel: A folded stack of cells that swings out to make electricity. Its output follows the sunlight, never its facing.
Solid booster: An engine and its own sealed propellant in one case. No throttle, no shutdown, no refuelling: it burns flat out until its grain is spent. Its Length slider sets how long that takes, its Burn rate how hard it pushes.
Solid fuel: The grain cast into a solid booster. It never leaves the case it burns in, and no two boosters share any.
Sub-assembly: A piece of a ship saved to be added to other rockets — a satellite, a lander — kept under your account like your saved ships. See Save and reuse a sub-assembly.
Sound barrier: The steep rise in drag as an aircraft nears Mach 1, peaking just past it. A jet that cannot push through it stops just short of the speed of sound.
Space Center: The screen behind the hangar's Space Center button (the dome on the bottom bar): the buildings you own on a world and their levels.
Spacewalk: An astronaut going out of the hatch and across open space into another ship of yours within 50 m, with no docking — an EVA. Only astronauts do it. See Walk across to another ship.
Span: How far forward a warp carries the ship along its own orbit, set in hours or days on the drive's Skip slider. Everything aboard lives every second of it.
Speed mode: What the navball's speed means: ORBIT, SURFACE or TARGET. Tap the navball to cycle it.
Spent: A parachute that has been used: cut in flight, or collapsed at touchdown. It stays on the ship and will not open again until an engineer repacks it.
Sphere of influence: Where one world's pull is the one that matters. Crossing its edge hands your ship to the next world, marked SOI on the map.
Ghost: Another player's ship that its owner has not opened — or any other player's ship while your own carries no insurance cover: drawn where it is, beside you (faded) and on the map once your Comm Station is at level 2, and solid to nothing. See Other players' ships.
Cover (insurance): A policy on one ship, switched on from a command part's sheet in flight and paid from your credits for 24 hours at a time, renewed on the hour while the switch stays on. A ship needs it to be open and to touch any other player's ship; when another player's flight breaks a covered ship, the insurer puts it back. See Insurance cover, claims and pilot rating.
Pilot rating: A figure from 0 to 1,000, starting at 500, that sets what cover costs: it falls when a flight of yours breaks another player's ship, rises with clean visits and salvage, and drifts back toward 500 while under it. A missed player contract costs 50 and a delivered one earns 10. Under 250, no cover can be had and no player contract taken. See Insurance cover, claims and pilot rating.
Collision course: A new orbit that brings your ship within the world's collision distance of another player's ship. Whoever set the last one is at fault when the two meet: the rating fall is theirs, and their ship is not rebuilt. A red chip at the top left of the flight screen warns whichever pilot is flying. See Insurance cover, claims and pilot rating.
Salvage: Another player's wreck — a stage or ship nothing commands and nobody insures — brought down and recovered with your own ship. Its owner is paid its price, and your pilot rating goes up. Solid to everybody, cover or not. See Insurance cover, claims and pilot rating.
Price (station): What a sharing ship's owner charges for each unit another player takes out, or pays for each unit brought in. Set on a command part; with no price, that resource is not traded with other players that way. See Put prices on your station.
Share resources (ship): A ship whose owner turned on Share resources with other players on one of its command parts. A player docked with it may pump fuel, power or food to and from it through the joined rings, at the prices its owner sets; an unpriced resource does not cross. See Docking with another player's ship.
Open (ship): A ship whose owner turned on Open to other players on one of its command parts. Other players meet it hull to hull, for better and for worse, and may dock with it. An open ship is always insured: the switch buys its cover, and cover that ends closes it. See Other players' ships.
Joined ships: Two players' ships docked to each other. They are never merged: they are held together as one rigid body and stay two ships, each with its own owner, name, crew and controls — but a push from either moves both. See Docking with another player's ship.
Space station: A ship with the Space station switch turned on. It absorbs whatever docks with it instead of being absorbed: the pair keeps the station's name and its place in your fleet. See Rendezvous and docking.
Stage: One step of the staging order: the parts that act together on one tap of STAGE.
Stage lock: The padlock on STAGE: hold the button and pull up until it pops to lock or free it. Locked, a tap fires nothing. See Lock the stage button.
Staging: The ordered list of what fires when: engines light, separators let go, parachutes deploy or cut.
Standing mission: A Programme mission that is held rather than flown: so many relays in orbit, so many Meek in space, kept for so many days. The world counts it whether the game is open or not.
Stationary orbit: The one circular orbit round a world that takes exactly one of its days, flown the way it turns, so a ship there hangs over the same spot. Moons have none. Every world’s is on the worlds reference.
Stall: What happens when a wing meets the air at too steep an angle: the lift falls away and the drag climbs. A wing's card gives the angle.
Stabiliser: The small horizontal wing on an aeroplane's tail that keeps its nose pointed where it flies.
Stowed: Folded away in its housing. A stowed panel makes nothing, a stowed dish hears nothing, and both are far tougher.
Supersonic: Going faster than sound travels through the air around you. A pale cone trails the ship as it happens.
Surface gravity: How hard a world pulls at its own ground. It sets what thrust-to-weight your ship has there.
Science Lab: An eight-metre crewed module that turns the data your instruments gather into discovery, at a rate set by how far from home it is standing. It earns for as long as you leave it there.
Data: Raw measurements aboard a ship, waiting for a laboratory to work through them. Made by taking a reading somewhere the lab has not analysed before, and weighing nothing.
Bench: A Science Lab's three seats. Only Scientists sit in them, and how many are filled decides how fast the lab works through its data.
Survey: The record of which places you have measured. Each instrument at each place pays discovery once, the first time you read it.
Symmetry link: The tie between a part and its mirror. Move, resize or delete one and the other follows. A part can hold several: a fin paired on its booster is also tied to its copy on the mirrored booster, so all four move together. Links are made for you as you build: a part attached to one member of a pair is copied onto the other and tied to it.
Target: Another ship you have marked on the map. The navball and a chip then show where it is and how fast you close on it, and in docking mode the TGT toggle aims the thumb pad at it and holds the view on your own ship, nose up.
Tech node: One purchase on the tech tree. It puts parts in the palette.
Tech tree: Every tech node, arranged by tier. Opened from the Research Centre; paid for in discovery.
The Meek: The people who fly your rockets: astronauts, scientists, engineers, tourists and the rest. Recruited at the Astronaut Center.
Thermometer: The instrument that reads air temperature in kelvin, or its own skin where there is no air.
Throttle: The lever at the flight screen's lower left. It sets how hard the lit engines push, from 0 % to 100 %. Sliding the yellow grip in its handle to the left locks it in place. See Lock the throttle.
Thrust: The engines' push. The hangar draws it as the magenta arrow.
Tidally locked: A moon that turns once for every lap of its planet, so it keeps the same face toward it. Every moon in the system is.
Tier: A band of the tech tree. The Research Centre's level decides how many tiers you may buy from.
Time warp: Running the world faster than real time, from 1× to 5000×. Sandbox only, and only while coasting clear of the air.
Tips: Short pieces of advice about the screen you are on, opened from the round question-mark button at the right edge of the screen, and opening by themselves as you arrive until you untick Show tips on this screen. Read the tips.
Toast: A line the game slides onto the screen to tell you something happened. It fades on its own, or swipe it left or right to clear it at once and show the next one.
Tourist: A trade you never hire. Contracts hand them to you as free passengers and take them back at the end.
Tourist run: A contract that hands you passengers to fly somewhere and bring home. It finishes on the recovery, not the landing.
Transport: A contract that pays you to carry something rather than to prove a part: a passenger, a package, a satellite. It never retires, and the board keeps two of its ten offers for it.
Trade: What a Meek does: astronaut, scientist, engineer, medic, botanist, nuclear scientist or tourist.
Transfer: The long coast between leaving one world's sphere of influence and arriving at another's. It is planned as a maneuver node and takes hours or days of world clock.
Transfer resources: Pumping a load — propellant, charge, food, waste — from one store into another in flight, including between two docked ships. On any store's sheet.
Trim: Where an aeroplane's elevator rests with your hands off the buttons, set with the tail's Elevator trim slider. See Trim the elevator.
TWR: Thrust-to-weight ratio: the engines' push divided by the rocket's weight. Above 1.0 it can lift off.
Under way: A contract you have accepted and not yet finished. Your Administration's level is how many you may have at once.
Undock: To cut a docked joint, by tapping Undock on the port or by staging it. The two halves are pushed gently apart.
Unit: How every resource is counted, written u. Each unit but electricity has a weight the ship carries.
Unlock: Buying a node on the tech tree, and the label on the button that does it. Once bought, a node is yours for the rest of the game.
V/S: Vertical speed, beside the navball: how fast the ship is rising or falling. The number a landing is judged on.
Vent: Emptying every Antimatter Container aboard at once, safely, from a container's sheet. The only safe way to bring a container down.
Bubble: The sphere a warp drive closes round its ship, centred on the drive and quoted as a diameter on its card. Anything outside it when the wall closes is destroyed, so the bubble is also the largest ship that drive can carry. See Warp drives.
Wall: The skin of a warp bubble, and the only sky a radiator has while the bubble is closed. Each drive's wall has its own temperature: 350 K, 600 K or 800 K.
Warp: Carrying one ship forward along its own orbit by a span you set, inside a bubble. No clock moves and nothing else in the solar system moves either. See Warp drives.
Warp drive: The part that closes the bubble. It makes no thrust and adds no Δv; it spends antimatter to buy time.
Waste: What a crew leaves behind: one unit for every unit of food eaten. Pods and cabins keep room for it, it launches empty, and once every store aboard is full the rest goes overboard. See Waste.
Weight: How hard a world pulls on a ship's mass, in kilonewtons. The same ship weighs a sixth as much on the Moon as on Earth.
Whip: A fixed antenna with no latch: it works from the pad, cannot be staged and cannot be stowed.
Wingspan: How far a wing reaches from tip to tip, out of the screen toward you. Never drawn; set with the Wingspan slider.
Wide mine: The 8 m helium-3 chain sold on tier 5 — the MR-8, H3-8, AC-8 and AM-8 — which fuels the crewed drives. See Two sizes of mine.
Working fluid: What runs inside a radiator's heat pipes, and the temperature it runs at: water at 450 K, potassium at 700 K, sodium at 900 K. The hotter the fluid, the more the fin sheds and the hotter a sky it can shed into.
World: A planet, moon or the sun. Every world has its own gravity, and some have air.
World clock: The time the shared world runs on. It keeps going while the game is closed.
Wrench: The engineer's stat. An engineer aboard can repack a spent parachute; how high the wrench is does not change that yet.
Δv (delta-v): How much a ship can change its speed with the fuel aboard, in m/s. The measure of how far a stage can take you.