• Halley, Edmund, 1
• Halpern, Mark, 1, 2
• Harrison, Ed, 1
• Hauser, Mike, 1
• Hawking, Stephen, 1, 2, 3, 4, 5
• helium, 1, 2, 3
  • liquid, 1, 2, 3, 4, 5
• helium-3, 1
• Herman, Robert, 1, 2, 3, 4, 5, 6
• Hogan, Craig, 1
• horizon see light horizon, cosmic
• horizon problem, 1
• hot dark matter see dark matter
• Hoyle, Fred, 1, 2, 3, 4, 5
• Hubble, Edwin, 1, 2
• Hubble constant, 1
• Hubble Space Telescope, 1, 2
• Hubble’s law, 1, 2, 3
• Humason, Milton, 1
• hydrogen, 1, 2