Space Facts

Scientific, historical and cultural facts about space, galaxies, the planets and other objects in the solar system. The latest discoveries and interesting space-related features can be found on the blog, while the gallery highlights graphics and diagrams that illustrate more aspects of the universe.

Check out some interesting space facts below:

  • Space does not begin at a specific altitude above the Earth, but the Kármán line at 100km is a commonly used definition.
  • The temperature in the void of space is about −270.45 °C.
  • Space is a hard vacuum, meaning it is a void containing very little matter.
  • The space between galaxies is not completely empty but has an average of one atom per cubic meter.
  • There are an estimated 100-400 billion stars in our galaxy, the Milky Way.
  • The universe is observed to be 13.8 billion years old has been expanding since its formation in the Big Bang.
  • In the observable universe there are an estimated 2 trillion (2,000,0000,000,000) galaxies.

Find more facts about each of the planets below:

More facts about the solar system below:

Find more facts about different galaxies below: