FREEDOM

retired

Technology DemonstrationLEOCOSPAR 1998-067KSLaunched 12/9/2016

Admin Edit

Mission & Launch

Launch Mission: HTV-6
Launch Vehicle: H-IIB
Launch Date: 12/9/2016
Last Contact: 2/5/2017

Orbit & Mass

Orbit Class: LEO
Altitude: 400 km
Inclination: 51.64 deg
Dry Mass: 1 kg
Total Mass: 1 kg

Payload Classification

Organizations

Operator: Tohoku University
Manufacturer: Nakashimada Engineering Works Ltd.

Registry

COSPAR ID: 1998-067KS
UN Registration: ST/SG/SER.E/862

Mentions

173

All verified mentions of this spacecraft in source documents.

NASA intends to use SR-1 Freedom operational data to refine life-support and propulsion systems for future Mars exploration.

CapabilityPlanValue 3.6Apr 15, 2026NASA Shifts Focus to Permanent Lunar Base and Nuclear Propulsion

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SR-1 Freedom will use nuclear electric propulsion to transport payloads to Mars.

Space Reactor-1 Freedom will use nuclear electric propulsion to travel to Mars and deliver the Skyfall payload.

CapabilityPlanValue 4.0Apr 15, 2026White House directs accelerated space nuclear power initiative

Space Reactor-1 Freedom will use a mature uranium fuel form and Brayton power conversion to deliver more than 20 kilowatts of electrical power.

CapabilityValue 4.0Apr 15, 2026White House directs accelerated space nuclear power initiative

Space Reactor-1 Freedom is designed to repurpose NASA’s nearly built Power and Propulsion Element spacecraft bus.

CapabilityGeneralValue 4.0Apr 15, 2026White House directs accelerated space nuclear power initiative

Space Reactor-1 Freedom is targeted for a December 2028 launch.

PlanValue 4.0Apr 15, 2026White House directs accelerated space nuclear power initiative

NASA, the Department of Energy, and the Department of Defense aim to field a 20-kilowatt space-based reactor by 2028 aboard SR-1 Freedom.

PlanCapabilityValue 4.0Apr 15, 2026NASA Shifts Focus to Permanent Lunar Base and Nuclear Propulsion

NASA plans to launch the SR-1 Freedom, a nuclear-powered interplanetary spacecraft, by 2028.

PlanCapabilityValue 4.4Apr 15, 2026NASA Shifts Focus to Permanent Lunar Base and Nuclear Propulsion

Space Reactor-1 Freedom will start its fission reactor within 48 hours of escaping Earth’s gravity and power electric thrusters.

PlanCapabilityValue 4.0Apr 15, 2026White House directs accelerated space nuclear power initiative

Space Reactor-1 Freedom will be the first spacecraft to use a nuclear fission reactor for propulsion beyond Earth orbit.

CapabilityPlanValue 4.0Apr 15, 2026White House directs accelerated space nuclear power initiative

Jeremy Hansen and NASA astronaut Christina Koch manually flew Orion during Artemis 2 to test its six-degree-of-freedom attitude controls.

CapabilityPlanValue 4.0Apr 5, 2026Video: Artemis 2 flight day 4 highlights – Hansen takes the controls as Orion nears the Moon

NASA plans to launch SR-1 Freedom to Mars in the late 2028 launch opportunity.

PlanGrowthValue 4.0Mar 30, 2026Igniting a new vision for NASA

SR-1 Freedom will spend about one year traveling to Mars and will deploy three small helicopters on arrival to scout a future landing site.

PlanCapabilityValue 4.0Mar 30, 2026Igniting a new vision for NASA

NASA plans to prioritize the Space Reactor 1 Freedom nuclear power system as part of its surface infrastructure strategy.

PlanCapabilityGeneralValue 3.0Mar 30, 2026Artemis and NASA’s Return to the Moon

SR-1 Freedom will use a 20-kilowatt fission reactor to power the Power and Propulsion Element.

CapabilityValue 4.5Mar 30, 2026Igniting a new vision for NASA

NASA's Space Reactor 1, or SR-1 Freedom, will demonstrate nuclear electric propulsion.

CapabilityPlanValue 4.0Mar 30, 2026Igniting a new vision for NASA

NASA will launch Space Reactor-1 Freedom, a nuclear-powered interplanetary spacecraft, to Mars before the end of 2028.

PlanCapabilityValue 4.5Mar 29, 2026NASA goes big on the Moon and Mars

The SR-1 Freedom mission aims to send a nuclear-powered craft to Mars in 2028.

PlanCapabilityValue 4.2Mar 27, 2026With Artemis Changes, Europe is Left Holding the Bag

NASA and the U.S. Department of Energy are partnering on the Space Reactor-1 Freedom effort.

RelationshipsValue 4.0Mar 27, 2026NASA Unveils Initiatives to Achieve America’s National Space Policy

NASA plans to launch Space Reactor-1 Freedom, the first nuclear powered interplanetary spacecraft, to Mars before the end of 2028.

PlanCapabilityValue 4.0Mar 27, 2026NASA Unveils Initiatives to Achieve America’s National Space Policy