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British startup Pulsar Fusion is developing Sunbird, a nuclear fusion-powered rocket that could significantly reduce travel time to outer planets like Mars and Pluto. An orbital demonstration is planned for 2027.

Key Features of Sunbird

• Maximum Speed: Up to 805,000 km/h, surpassing the Parker Solar Probe (692,000 km/h), the fastest human-made object to date.
• Travel Efficiency: Could enable missions to Pluto in just 4 years, and cut travel time to Mars by nearly 50%.
• Payload Capacity: Capable of delivering up to 2,000 kg to Mars in six months.
• Functionality: Unlike chemical rockets like SpaceX’s Starship, Sunbird would act as an interplanetary booster, attaching to spacecraft and possibly operating between charging stations in Low Earth Orbit (LEO) and Mars orbit.

About Nuclear Fusion Propulsion

Nuclear Fusion aims to replicate the process that powers stars — the fusion of atomic nuclei to release energy. Unlike nuclear fission, fusion is cleaner, offers higher energy output, and produces minimal radioactive waste.

Types of Nuclear Propulsion Systems

Propulsion Type                                                           Description

Nuclear Thermal Propulsion (NTP)             Uses a nuclear reactor to heat liquid hydrogen which

                                                                            turns to plasma and produces thrust. Provides high exhaust

                                                                            velocity and can increase payload efficiency 2–3 times

                                                                            over chemical rockets. Ground tests began in the 1950s.

Nuclear Electric Propulsion (NEP)                Converts reactor heat into electricity to power ion thrusters,

                                                                            which gradually reach high speeds. Components include a

                                                                                               compact reactor core, electric generator, heat rejection

                                                                                               system, and electric propulsion system. Unlike solar power,

                                                                           nuclear sources ensure consistent energy beyond Mars.

Challenges in Fusion Rocket Development

• Fusion systems are currently large and heavy, posing difficulties in miniaturisation for spaceflight.
• Fusion on Earth is hard to replicate due to atmospheric constraints; space offers a more natural environment for fusion reactions.

Global Efforts and Timeline

Apart from Pulsar Fusion, companies like Helicity Space and General Atomics (backed by NASA and Lockheed Martin) are also advancing fusion-powered space propulsion systems, with testing planned around 2027.