Advances in Space Technology: Everything You Need to Know

Liquid Fueled Rockets

Early rockets used solid propellants which limited their capabilities. However, German engineers in WWII developed liquid-fueled rockets such as the V2 which allowed for larger and more controlled thrust. After the war, liquid fuels became the standard propellants for rockets. Modern rockets use cryogenic liquid hydrogen and liquid oxygen which maximizes performance. The Saturn V rocket that took astronauts to the Moon used a first stage with five massive F-1 engines that each generated 1.5 million pounds of thrust using liquid oxygen and kerosene.

Staged Rockets

An innovation that was critical for reaching space was multi-staged rockets. Because a rocket has to carry all of its fuel at liftoff, minimizing empty mass as fuel is expended is crucial. Rocket stages which are discarded in sequence allowed rockets to become much more powerful. The three-stage Saturn V was instrumental in getting to the Moon. Modern rockets utilize two or more stages to efficiently get to orbit. SpaceX's Falcon Heavy uses two reusable stages and a third expendable stage to generate over 5 million pounds of thrust at liftoff.

Reusable Rockets

Another major innovation has been reusable rockets which return their booster stages to Earth so they can be reflown on future launches. This was pioneered by SpaceX with their Falcon 9 first stage boosters which can land propulsively back on landing pads or drone ships after delivering their payloads to orbit. Reusability significantly reduces the cost of launch to space by allowing expensive rocket components to be reused 10 times or more, a major step towards affordable and sustainable space access.

Satellites and Space Probes

Once in space, a variety of technologies have expanded our capabilities to utilize and explore the space environment. One foundational technology has been satellites which not only provide communications, navigation, Earth observation and other services from orbit but have also allowed robotic exploration across the solar system.

Miniaturization

Early satellites were large, multi-ton behemoths but the electronics revolution enabled mass reductions in satellite size and weight. Today CubeSats as small as a few kilograms provide capabilities that once required a dedicated full-scale satellite. Small satellites have reduced costs and allowed new space players easier access to orbit. Groups of CubeSats can also work cooperatively in swarms and constellations to provide capabilities that once required a single large spacecraft.

High-Efficiency Solar Arrays

Generating power in space has been revolutionized by improvements in solar array technology. Ultra lightweight solar panels utilizing high-efficiency photovoltaic cells can generate significantly more power per kilogram than earlier solar arrays. Expandable arrays like ATK’s MegaFlex and Orbital ATK’s UltraFlex have deployed from small volumes to provide tens of kilowatts on orbit. High power solar electric propulsion systems are enabling new long-endurance spacecraft for exploration and other applications.

Advanced Materials

New materials like composites and microelectromechanical systems (MEMS) have enabled reductions in size and mass while also improving the precision, control and maneuverability of spacecraft and instruments. Materials advances have been critical for spacecraft like Hubble and James Webb which deploy large yet incredibly precise optical systems to enable revolutionary new views of the universe.

Propulsion Breakthroughs

Advanced propulsion technologies are critical for long duration space missions. NASA’s Dawn spacecraft used high-efficiency ion thrusters to rendezvous with the asteroids Vesta and Ceres. Solar sails which harness the tiny but persistent pressure of sunlight hitting a large, ultra-thin and lightweight reflective membrane have been demonstrated by The Planetary Society’s LightSail 2 spacecraft. New propulsion technologies will enable ambitious missions to destinations deeper in our solar system and beyond.

Planetary Landers

Getting spacecraft safely to the surface of other planetary bodies is extremely challenging yet fundamental for detailed planetary study. Engineers have developed robust systems for decelerating within a planet’s atmosphere and soft landing, allowing landers and rovers to successfully reach the surfaces of Mars, Venus, Titan and other bodies. Future planetary landers will push new innovations in autonomous precision landing and hazard avoidance.

Human Spaceflight

For human space travel, major technology innovations have been required across launch systems, spacecraft, life support systems spacesuits and more. Critical developments include:

Space Capsules

Capsule spacecraft with ablative heat shields provided the capability to launch humans into orbit and return them safely. Mercury, Gemini and Apollo capsules paved the way for space stations and the space shuttle. Commercial crew capsules from SpaceX and Boeing will soon provide regular crew access to the International Space Station from American soil for the first time since 2011.

Space Stations

Modular space stations that can be assembled piecewise have allowed humans to establish a permanent foothold in space. The International Space Station has now maintained a continuous human presence in orbit for over 20 years. Future space stations will pave the way for travel deeper into the solar system.

Spacesuits

Specialized suits allow humans to survive and work in the vacuum and temperature extremes of space. Suits for launch and reentry like NASA’s SCAPE suit provide emergency protection while the Extravehicular Mobility Unit (EMU) has allowed spacewalkers to work externally on satellites and space station assembly. Next-gen suits will improve comfort and mobility for lunar exploration.

Closed-Loop Life Support

Future long duration missions beyond Earth orbit will require closed-loop life support systems where water, oxygen and other essentials are recycled inside spacecraft and outposts. The International Space Station has demonstrated increasingly efficient life support and future systems can reach over 90% oxygen recovery efficiency from exhaled CO2 to enable multi-year missions to the Moon, Mars and beyond.

Space Observatories

Some of the most transformative space technology has enabled space telescopes that have revolutionized astronomy and cosmology by revealing the mysteries of our universe.

Visible and Ultraviolet Telescopes

The Hubble Space Telescope has imaged astronomical objects across the electromagnetic spectrum from ultraviolet to infrared wavelengths. Upcoming flagships like NASA’s James Webb Space Telescope and ESA’s Euclid will examine the formation of galaxies and characteristics of exoplanets at longer infrared wavelengths. Together, these observatories are providing unprecedented views into the evolution of galaxies, stars, exoplanets and our cosmic origins.

X-Ray and Gamma Ray Telescopes

Looking at higher energy X-ray and Gamma ray light allows glimpses into some of the most energetic processes in the cosmos. NASA’s Chandra X-ray observatory along with ESA's XMM-Newton have examined energetic sources like black holes and neutron stars. NASA’s upcoming Imaging X-ray Polarimetry Explorer (IXPE) will provide new insights into exotic cosmic accelerators like pulsars and supernova remnants.

Radio Telescopes

At radio frequencies, telescopes can reveal processes obscured at higher frequencies by dust and gas. Networks of radio telescopes using interferometry to function as a single massive telescope have provided unprecedented detail. The Atacama Large Millimeter/submillimeter Array (ALMA) has imaged protoplanetary disks revealing the formation of new solar systems. Breakthroughs from observatories like the upcoming Square Kilometer Array will push the boundaries of radio astronomy.

Gravitational Wave Detectors

By sensing ripples in spacetime caused by merging black holes and neutron stars, gravitational wave detectors like LIGO are opening up a new field of multi-messenger astronomy. The space-based LISA observatory will detect lower frequency gravitational waves inaccessible from Earth beginning in 2034. The ability to both see and sense these cosmic events provides game-changing insights into the most extreme astrophysical objects.

What's Next?

The list of technological achievements enabling space exploration goes on and on. At the same time, there is still much progress to be made and many capabilities that have not yet been realized. As we move forward, critical areas for continued innovation include:

• Affordable Launch – Continuing to improve rocket reusability and identify new launch technologies like air-launch and electromagnetic rail guns.
• Extremely Large Telescopes – Building observatories beyond the James Webb Space Telescope that can directly image exoplanets.
• Advanced Spacecraft Propulsion – Moving beyond chemical rockets to allow faster transit throughout the solar system with technologies like nuclear fusion rockets.
• Surface Infrastructure – Developing the habitats, power systems, communications networks and vehicles required for sustained exploration of planetary surfaces.
• In-Situ Resource Utilization – Using local space resources for fuel, building materials and life support to enable self-sufficiency and permanent settlements.
• Spacecraft Autonomy – Improving autonomous spacecraft capabilities will be essential as distance and communication lag increases for ambitious exploration missions.
• Spacecraft Resilience – Technologies for self-repair, damage avoidance and dealing with harsh deep space environments during long duration robotic and crewed missions.

We have accomplished a staggering amount in a relatively short period of time. As we build off these achievements, the opportunities for advancing space technology and expanding the horizons of exploration appear limitless. The coming decades will see exciting new breakthroughs that will continue to transform our knowledge of the universe and our capability to journey ever deeper into space.