Reusable launch vehicle facts for kids

A reusable launch vehicle is a type of rocket or spacecraft that can be used more than once to carry things into outer space. Imagine a car or an airplane: you don't build a new one every time you want to travel. Reusable launch vehicles work in a similar way!

The main idea is to recover parts of the rocket, like its stages or engines, after they've done their job. This means you don't have to build brand new parts for every single launch. This can help make space travel much cheaper. However, it costs money and effort to recover these parts and get them ready for their next flight.

Reusable rockets might be a bit heavier than rockets that are only used once. This is because they need extra equipment like heat shields to protect them when they come back into Earth's atmosphere. They also need special fins or parachutes to help them land safely. Some even need special landing spots, like runways or floating drone ships in the ocean.

People have dreamed about reusable space vehicles for a long time, even in science fiction. The first real reusable vehicles, like the Space Shuttle and Energia, were built in the 1960s and 1970s. After a quiet period, private companies like SpaceX and Blue Origin started developing them again in the 2000s. Now, many new rockets are being designed to be reusable, which is a big step for space travel!

Recovery of a Falcon 9 first-stage booster after its first landing.

How Reusable Rockets Work

Reusable launch systems can be either fully reusable (meaning all parts come back) or partially reusable (meaning only some parts come back).

Fully Reusable Systems

A fully reusable launch vehicle means that every part of the rocket that goes into space comes back to Earth and can be used again. As of 2024, several companies are working on these.

• SpaceX Starship: This is a huge rocket being developed by SpaceX. It's designed so that both its first stage (called Super Heavy) and its second stage (called Starship) can land back on Earth and be flown again. It has had several test flights, and in June 2024, both parts landed softly for the first time!
• Blue Origin's Project Jarvis: Blue Origin is also working on a fully reusable rocket, but they haven't shared many details yet.
• Stoke Space: This company is also developing a rocket that aims to be fully reusable.

Partially Reusable Systems

Most reusable rockets today are partially reusable. This means they reuse some important parts, but not all of them.

Reusing Specific Parts

Some rockets reuse only certain components:

• Space Shuttle: This famous space vehicle reused its solid rocket boosters and the main orbiter (the part that looked like a plane). However, the large external fuel tank was thrown away after each launch.
• ULA's Vulcan Centaur: This rocket plans to reuse only its first-stage engines. These engines will detach and fall back to Earth, protected by an inflatable shield, and then be recovered.
• Falcon 9 Engines: The engines on the Falcon 9 rocket are very tough. One engine has even flown to space 22 times! This shows how durable reusable parts can be.

Reusing Liftoff Stages

The most common type of reusable rocket today reuses its first stage, which is the part that gives the rocket its initial big push off the ground.

• Falcon 9 and Falcon Heavy: These rockets from SpaceX are the only ones currently in use that land their first-stage boosters back on Earth. They either land on a special pad near the launch site or on a floating ship in the ocean.
• Aircraft-launched Rockets: Some rockets are launched from airplanes high in the sky. The airplane itself is reused, making it a partially reusable system. An example is the Orbital Sciences Pegasus.

Reusing Orbital Stages

The "orbital insertion stage" is the part of the rocket that pushes the spacecraft into orbit.

• Space Shuttle Orbiter: The Space Shuttle was unique because its orbiter (the plane-like part) was also the orbital insertion stage, and it was reused.
• Starship: The Starship spacecraft is designed to be the second stage that goes into orbit, and it's meant to be fully reusable.

Reusable Spacecraft

Besides rockets, some spacecraft themselves are designed to be reused.

• Space Shuttle Orbiter: This vehicle was both a part of the launch system and a reusable spacecraft that could stay in orbit.
• Dragon 2 and X-37: The Falcon 9 rocket often carries reusable spacecraft like the Dragon 2 capsule (which carries astronauts and cargo) and the X-37 spaceplane.
• Modern Reusable Spacecraft: Today, vehicles like the X-37, Dream Chaser, and Dragon 2 are designed to be reused.

For a long time, almost all spacecraft were only used once. But in the 2010s, things started to change. For example, NASA began allowing SpaceX to reuse their Dragon 1 cargo capsules for missions to the International Space Station.

How Rockets Return to Earth

When a reusable rocket part comes back from space, it needs special systems to slow down and land safely.

Heat Shields

When a rocket part re-enters Earth's atmosphere, it travels incredibly fast and gets extremely hot due to friction with the air.

• Protection: Heat shields are like a protective skin that keeps the rocket from burning up. They can be made of special heat-resistant tiles or even inflatable structures.
• Saving Money: Heat shields help save expensive parts, like engines, by allowing them to survive the fiery re-entry.

Retrograde Thrust

This means firing rocket engines in the opposite direction of travel to slow down.

• Braking in Space: Rockets like the Falcon 9 and New Shepard use their engines to slow down both for re-entry and for a soft landing.

Landing Systems

Reusable rocket parts can land in different ways.

Parachutes and Airbags

This method involves using parachutes to slow the vehicle down, often followed by a splashdown in the ocean or a cushioned landing on land.

• Splashdown: Many early spacecraft and parts like the Space Shuttle's solid rocket boosters landed in the water using parachutes.
• Cushioned Landings: Some capsules, like the Soyuz or SpaceX Dragon, use parachutes and then fire small engines or deploy airbags right before touching down to make the landing softer.

Horizontal (Winged) Landing

These vehicles land much like an airplane, using wings to glide down onto a runway.

• Space Shuttle Orbiter: The Space Shuttle orbiter was a famous example. It glided back to Earth and landed on a runway.
• Spaceplanes: Many proposed and experimental reusable vehicles, like SpaceShipTwo, are designed as spaceplanes that land horizontally.
• Weight: Vehicles that land this way need wings and landing gear, which add weight. This can reduce how much payload they can carry.

Vertical (Retrograde) Landing

This is when a rocket stage lands upright, using its engines to slow down just before touchdown.

• Falcon 9 and Falcon Heavy: SpaceX pioneered this method for orbital rockets. Their first stages land vertically on a landing pad or a drone ship.
• New Shepard: Blue Origin's suborbital rocket, New Shepard, also lands vertically back at its launch site.
• Starship: The SpaceX Starship is designed for vertical landing for both its booster and its spacecraft.
• Fuel Use: This method uses some of the rocket's fuel for landing, which means a little less payload can be carried into space.

Challenges for Reusable Rockets

Even though reusable rockets offer many benefits, there are some challenges.

Extra Weight

Reusable rocket stages are heavier than single-use ones. This is because they need all the extra equipment for landing, like heat shields, landing gear, and extra fuel for the landing burn. This added weight can sometimes reduce the amount of cargo the rocket can carry into space.

Refurbishment

After a reusable rocket lands, it needs to be checked, cleaned, and repaired to get it ready for its next flight. This process can take time and cost money. Rockets can only be reused a certain number of times before they need to be retired. However, companies like SpaceX have shown that their reusable rockets can fly many times, even for missions carrying astronauts!

History of Reusable Rockets

The idea of reusable rockets has been around for a long time, but making them work has been a big challenge.

20th Century

• Early Ideas: Scientists like Wernher von Braun thought about reusable rockets in the 1940s and 1950s.
• Space Shuttle: The US Space Shuttle was the first reusable orbital launch vehicle, starting flights in 1981. It reused its main orbiter and solid rocket boosters.
• Delta Clipper (DC-X): In the 1990s, the McDonnell Douglas DC-X was a prototype that showed how a rocket could take off and land vertically, controlled by computers. It proved that rapid reuse was possible.

21st Century

• Ansari X Prize: In the early 2000s, this competition encouraged private companies to build reusable suborbital vehicles. Scaled Composites won with their SpaceShipOne, which flew to the edge of space twice.
• SpaceX's Breakthrough: In 2012, SpaceX began testing reusable rocket parts. On December 21, 2015, a Falcon 9 rocket successfully landed its first stage vertically after sending satellites into orbit. This was a huge moment!
• Routine Reuse: Since then, SpaceX regularly recovers and reuses its Falcon 9 and Falcon Heavy first stages. They even reuse the nose cones (fairings) that protect the satellites!
• New Shepard: Blue Origin's New Shepard suborbital rocket also successfully lands vertically and has been reused many times.
• Rocket Lab: This company is working on reusing the first stage of their Electron rocket, planning to catch it in mid-air with a helicopter!
• Future Rockets: Many new rockets, like Starship, New Glenn, and Neutron, are being developed with reusability in mind.

Returning to the Launch Site

Some reusable rockets can even fly back and land very close to where they launched. This is called "Return to Launch Site" (RTLS).

• Space Shuttle and Buran: These spaceplanes could glide back to a runway near their launch site if needed.
• SpaceX and Blue Origin: Both companies have developed technologies for vertical landings.
• Falcon 9 and Falcon Heavy: SpaceX's rockets can land their first stages either on a landing pad near the launch site or on a floating ship in the ocean, depending on the mission.
• New Shepard: Blue Origin's New Shepard rocket always lands back at its launch site.
• Starship: SpaceX Starship is designed to have both its booster and spacecraft return and land vertically at the launch site.

List of Reusable Launch Vehicles

Company	Vehicle	Reusable Part	Launched	Recovered	Relaunched	First Launch	Status
NASA	Space Shuttle	Orbiter	135	133	130	1981	Retired (2011)
SpaceX	Falcon 9	First stage	334	290	263	2010	Active
Rocket Lab	Electron	First stage	49	9	0	2017	Active, relaunch planned
SpaceX	Falcon Heavy	Side booster	20	18	14	2018	Active
SpaceX	Starship	First stage	4	0	0	2023	Active, recovery planned
United Launch Alliance	Vulcan Centaur	First stage engine module	1	0	0	2024	Active, recovery planned
Blue Origin	New Glenn	First stage, fairing	0	0	0	2024	Planned
Rocket Lab	Neutron	First stage (includes fairing)	0	0	0	2025	Planned
Stoke Space	Nova	Fully reusable	0	0	0	2025	Planned
Roscosmos	Amur	First stage	0	0	0	2026	Planned
Relativity Space	Terran R	First stage	0	0	0	2026	Planned

List of Reusable Spacecraft

Company	Spacecraft	Launch Vehicle	Launched	Recovered	Relaunched	First Launch	Status
NASA	Space Shuttle orbiter	Space Shuttle	135	133	130	1981	Retired (2011)
NPO-Energia	Buran	Energia	1	1	0	1988	Retired (1988)
Boeing	X-37	Atlas V, Falcon 9, Falcon Heavy	7	6	5	2010	Active
SpaceX	Dragon	Falcon 9	46	44	24	2010	Active
NASA	Orion	Space Launch System	2	2	0	2014	Active, relaunch planned
Boeing	Starliner	Atlas V	3	2	1	2019	Active
CASC	Chinese reusable experimental spacecraft	Long March 2F	3	2	unknown	2020	Active, reusability unknown
Sierra Space	Dream Chaser	Vulcan Centaur	0	0	0	2024	Planned

List of Reusable Suborbital Vehicles

Company	Vehicle	First Launch	Recovered	Relaunched	Notes
Blue Origin	New Shepard	2015	20	17	Fully reusable.
Virgin Galactic	SpaceShipTwo (VSS Unity)	2018	5	4	Fully reusable.
Virgin Galactic	SpaceShipThree (VSS Imagine)				Fully reusable.

Images for kids

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  The McDonnell Douglas DC-X prototype showed how rockets could take off and land vertically.

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  Scaled Composites SpaceShipOne landing horizontally after being launched from a carrier airplane.

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  Falcon Heavy side boosters landing during a 2018 demonstration mission.