Exploration
at Goddard
At Goddard, exploration is a system that builds outward, grounded in understanding Earth, extending through the space environment, and enabling safe and sustained missions to the Moon, Mars, and beyond.
The Sciences and Exploration Directorate (SED) brings together complementary scientific disciplines that work in concert to make exploration possible. Each contributes in a distinct way, while collectively forming a unified exploration enterprise.
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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Solar System
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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Analemma over the Callanish Stones
If you went outside at the same time every day and took a picture that included the Sun, how would the Sun's position change? A visual answer to that question is an analemma, a composite image taken from the same spot at the same time over the course of a year. The featured analemma was composed from images taken every few days at noon near the village of Callanish in the Outer Hebrides in Scotland, UK. In the foreground are the Callanish Stones, a stone circle built around 2700 BC during humanity's Bronze Age. It is not known if the placement of the Callanish Stones has or had astronomical significance. The ultimate causes for the figure-8 shape of this and all analemmas are the tilt of the Earth axis and the ellipticity of the Earth's orbit around the Sun. At the solstices, the Sun will appear at the top or bottom of an analemma. The featured image was taken near the December solstice and so the Sun appears near the bottom. Equinoxes, however, correspond to analemma middle points -- not the intersection point. In two days there will be an equinox ("equal night"), when day and night are equal over all of planet Earth. Many cultures celebrate a change of season at an equinox. APOD's main NASA site is moving: From apod.nasa.gov to science.nasa.gov/apod