Level 1 — Absolute Beginner
A company in China is testing a new way to launch rockets into space. The idea uses a gas called carbon dioxide, or CO2.
CO2 is the same gas that makes bubbles in soda drinks like Coca-Cola. Under the right pressure, it can push things very hard.
In this new method, CO2 gas pushes the rocket up into the air first. The rocket's engines only turn on after it is already flying.
Engineers say this method could make launching rockets cheaper and safer. It also makes less pollution than older launch methods.
- company
- a business that makes or sells things
- launch
- to send something, like a rocket, up into the sky or space
- gas
- a substance, like air, that is not solid or liquid
- carbon dioxide
- a gas made of carbon and oxygen, also found in soda bubbles
- pressure
- a force pushing on something
- engines
- machines that produce power to move something
- cheaper
- costing less money
- pollution
- harmful substances released into the air, water, or land
Level 2 — Elementary
A Chinese aerospace startup has tested an unusual new launch system that relies on carbon dioxide, the same gas that gives Coca-Cola its fizz, rather than traditional rocket exhaust to get a small rocket off the ground.
The company, Z-Trak Space, based in Zhuzhou, Hunan province, uses supercritical carbon dioxide, a special state of the gas created under high pressure and temperature, to instantly generate a burst of gas that physically ejects the rocket from its launch platform.
Only after the rocket reaches a certain altitude do its main engines actually ignite, a technique known as a cold launch, which keeps hot exhaust fumes away from the ground equipment entirely.
Engineers behind the project say the approach could reduce the infrastructure needed at launch sites, allow rockets to be launched more frequently, and cut costs, all while producing no harmful emissions near the launch pad because carbon dioxide itself is non-toxic.
- aerospace
- relating to the science and technology of flight and space travel
- startup
- a newly created company, often focused on innovative technology
- exhaust
- the hot gases released by an engine after burning fuel
- supercritical
- a state of matter where a substance has properties of both a liquid and a gas
- ejects
- forcefully throws or pushes something out
- altitude
- height above the ground or sea level
- ignite
- to start burning or begin operating, as in an engine
- infrastructure
- the basic physical structures and equipment needed for something to operate
Level 3 — Intermediate
Chinese aerospace startup Z-Trak Space, founded just last year and based in Zhuzhou, Hunan province, has begun testing a cold-launch system that substitutes pressurized carbon dioxide for the conventional ignition-on-the-pad approach used by most orbital and suborbital rockets.
The system relies on supercritical carbon dioxide, a phase of the gas that exists once temperature and pressure simultaneously cross specific thresholds, enabling it to generate an instantaneous burst of high-pressure gas capable of physically ejecting a rocket from its platform before any combustion occurs.
Only once the vehicle reaches a designated altitude do its rocket engines ignite, a sequencing choice that keeps corrosive, high-temperature exhaust plumes entirely away from ground infrastructure, a departure from conventional launch pads that must be engineered to withstand direct engine blast.
Proponents argue the approach could meaningfully lower the capital costs of launch infrastructure, support higher launch cadences for China's expanding commercial space sector, and virtually eliminate toxic emissions at the pad, since supercritical carbon dioxide itself is non-flammable and non-toxic, unlike some traditional propellant combinations.
- suborbital
- describing a flight that reaches space but does not complete a full orbit of the Earth
- ignition
- the act or process of starting a fire or combustion
- thresholds
- points or levels at which something begins to happen or change
- combustion
- the process of burning, especially as a way to release energy
- sequencing
- the order in which a series of events or actions occurs
- corrosive
- capable of gradually destroying or damaging materials through chemical action
- cadences
- the rate or rhythm at which events repeat, such as launches
- propellant
- a substance used to provide thrust to a rocket or vehicle
Level 4 — Advanced
Z-Trak Space (Zhiyu Aerospace Technology), a Chinese aerospace startup founded only last year and headquartered in Zhuzhou, Hunan province, has begun flight-testing a cold-launch architecture that supplants the conventional on-pad ignition paradigm with a pneumatic ejection stage powered by supercritical carbon dioxide.
Supercritical CO2, a phase attained once temperature and pressure simultaneously exceed defined critical thresholds, exhibits liquid-like density alongside gas-like diffusivity, properties the company exploits to generate an instantaneous, high-pressure gas expansion capable of physically vaulting the vehicle clear of its launch platform before any propellant combustion is initiated.
Engine ignition is deferred until the vehicle attains a designated altitude, a sequencing strategy that entirely decouples the corrosive, high-enthalpy exhaust plume from ground support infrastructure, obviating the reinforced flame trenches and deluge systems that conventional pads require to survive direct engine blast.
Advocates contend the architecture could substantially compress the capital expenditure associated with launch infrastructure, sustain markedly higher launch cadences befitting China's rapidly scaling commercial space sector, and functionally eliminate toxic pad-level emissions, since supercritical carbon dioxide is inherently non-flammable and non-toxic, a stark contrast to hypergolic or cryogenic propellant combinations that demand extensive safety engineering.
- pneumatic
- operated by or relating to gas or air pressure
- paradigm
- a typical example or standard pattern of how something is done
- diffusivity
- the tendency of a substance to spread evenly through a space
- vaulting
- leaping or springing over or clear of something
- deferred
- put off until a later time
- high-enthalpy
- containing or releasing a large amount of heat energy
- obviating
- removing the need for something
- hypergolic
- describing propellants that ignite spontaneously on contact with each other, without a separate ignition source
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