astr0naaut:

‘Planetary Nebula’ (via HubbleColor)
sun-moon-planet-star:

Spiral Galaxy NGC 3310
ouruniversevisualized:

No one knows what dark matter is, but it constitutes 80 percent of the matter in our universe. By studying numerous dwarf galaxies — satellite systems that orbit our own Milky Way galaxy — NASA’s Fermi Gamma-ray Space Telescope has produced some of the strongest limits yet on the nature of the hypothetical particles suspected of making up dark matter. Short, narrated video.
credit: Wu, Hahn, Wechsler, Abel(KIPAC), Kaehler (KIPAC)