outer space: Quick Facts

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The Information Architects of Encyclopaedia Britannica

Last updated

Oct. 5, 2026

Facts

Also Known As	space

Photos and Videos

Voyager 1 in interstellar space

Astronaut holding a rainbow lollipop against a starfield, with arrows toward text reading: Sugar in Space?

An astronaut in space waves while surrounded by floating plastic debris including bottles, a bag, a straw, and a plate near Earth's orbit.

Examine the observable universe's place within the whole universe

Diagram of the Milky Way galaxy showing labeled locations of the Sun, Milky Way center, Sagittarius dwarf elliptical, and Canis Major dwarf, with axes marking 80,000 light-years.

Learn about space expansion and why gravity and electromagnetism are not affected when space expands

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Topics

Kármán line space exploration dark energy dark matter matter vacuum Universe Zone of avoidance Star Sun Eclipse Galaxy Cosmology gravity Solar system Star cluster Cosmic microwave background