Discover how we're driving the Nation's scientific progress through world-class research across Earth and Space sciences at Goddard’s Sciences and Exploration Directorate.
Earth Sciences
The Earth Sciences Division is the nation's technical innovator and essential data provider to support national infrastructure, scientific leadership, and economic resilience.
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Astrophysics
The Astrophysics Science Division leads America's quest to answer our most profound scientific questions, developing technologies with transformative applications in medicine, national security, and intelligence.
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Heliophysics
The Heliophysics Science Division advances understanding of the Sun and its interactions with Earth and the solar system, providing the foundational science that drives space weather research and solutions in collaboration with government, industry, and academia.
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Planetary Sciences
The Solar System Exploration Division powers space missions and leads human space exploration to the Moon and Mars through revolutionary research that charts the frontiers of our solar system and deepens our understanding of planetary system formation and evolution.
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To Fly Free in Space
What would it be like to fly free in space? About 100 meters from the cargo bay of a space shuttle, Bruce McCandless II was living the dream -- floating farther out than anyone had ever been before. Guided by a Manned Maneuvering Unit (MMU), astronaut McCandless, pictured, was floating free in space. During Space Shuttle mission 41-B in 1984, McCandless and fellow NASA astronaut Robert Stewart were the first to experience such an "untethered space walk". The MMU worked by shooting jets of nitrogen and was used to help deploy and retrieve satellites. With a mass over 140 kilograms, an MMU is heavy on Earth, but, like everything, is weightless when drifting in orbit. The MMU was later replaced with the SAFER backpack propulsion unit.