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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.

Hover to see how our science makes exploration possible
ASTRONOMY PICTURE OF THE DAY

Where Your Elements Came From

The hydrogen in your body and present in every molecule of water came from the Big Bang. There are no other appreciable sources of hydrogen in the universe. The carbon in your body was made by nuclear fusion in the interior of stars, as was the oxygen. Much of the iron in your body was made during supernovas of stars that occurred long ago and far away. The gold in your jewelry was likely made from neutron stars during collisions that may have been visible as short-duration gamma-ray bursts or gravitational wave events. Elements like phosphorus and copper are present in our bodies in only small amounts but are essential to the functioning of all known life. The featured periodic table is color coded to indicate humanity's best guess as to the nuclear origin of all known elements. The sites of nuclear creation of some elements, such as copper, are not really well known and are continuing topics of observational and computational research. 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