Space

Outer space represents a challenging environment for human exploration because of the dual hazards of vacuum and radiation. Microgravity also has a negative effect on human physiology that causes both muscle atrophy and bone loss. In addition to these health and environmental ...

From the Ashes of the First Stars - Primordial Quasar

From the Ashes of the First Stars - Primordial Quasar

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It's a Rocky World - Artist's Concept

It's a Rocky World - Artist's Concept

1600x1200, 298K

NASA - 10000 Galaxies, HST Ultra Deep

NASA - 10000 Galaxies, HST Ultra Deep

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Spacewalking Astronaut NASA STS-41-B EVA

Spacewalking Astronaut NASA STS-41-B EVA

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The Most Crowded Collision of Galaxy Clusters

The Most Crowded Collision of Galaxy Clusters

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