Hubble Space Telescope

Key Facts

1. 1

   Launched in 1990 at 559 km altitude; 1.5 million observations published in 20,000+ scientific papers

2. 2

   "Hubble Deep Field" (1995): pointed at a tiny dark patch of sky for 10 days — revealed 3,000 galaxies in that tiny area

3. 3

   Discovered that the universe is expanding at an accelerating rate — led to the concept of "dark energy" (70% of the universe)

Quick Reference