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Sciences and Exploration Directorate

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.

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ASTRONOMY PICTURE OF THE DAY

Earth's Shadow Visualized with Lunar Eclipses

What’s creating this giant hole in space? This is not a black hole — it’s a shadow. It’s Earth’s shadow. Since at least the time of Aristotle, people have noted that Earth's dark shadow on the Moon during a partial lunar eclipse is circular -- although never a whole circle. Using modern digital technology, though, the images of multiple lunar eclipses can be combined to show Earth's complete shadow. The featured image compilation by a perseistent astrophotographer is constructed from 22 years of lunar eclipses. The Moon is not eclipsed every month (moon-th) because the Moon's orbit is slightly tilted relative to Earth's orbit. Close inspection of some lunar eclipse images shows a faint blue band where Earth’s atmosphere filters out more red sunlight than blue. Later this week, a new lunar eclipse will occur and will be best visible in parts of North and South America, Europe, and Africa. APOD's main NASA site is moving : From apod.nasa.gov to science.nasa.gov/apod

Earth Observatory Picture

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HEASARC

Picture of the Week