NASA

Solar System Exploration
Eyes on the Solar System
Earth Observatory
 - Blue Marble | NEO
Visible Earth
Earth Observations
Earth Science Office  |  SatImages
MODIS Rapid Response
NASA Science
Goddard Space Flight Center
 - Solar Data Analysis Center 
 - Scientific Visualization Studio 
 - MODIS  |  AIRS
Goddard Institute for Space Studies
Goddard Earth Sciences | Giovanni
JFK Space Center
Glenn Research Center
NASA Multimedia  |  NASA TV
Visible Earth
Astronaut Photography
Picture of the Day
JSC Digital Image Collection
Jet Propulsion Lab
 - MISR  |  PhotoJournal
Hubble Space Telescope
hubblesite.org
Terra
Ocean Surface Topography
Space Shuttle Oceanography
Satellite Tracking
Ozone Hole Watch

ESA

Observing the Earth
Satellite Images
Spacecraft Operations
Science & Technology
Galileo Navigation
Arianespace

 DLR

Heavens Above

RB
SRTM
EOWEB
ESO
CNES.fr
BNSC.gov.uk
IKI.ru

USGS

Natl. Geospatial Program
EROS  |  Landsat
Earth as Art

Verschiedenes

Astronomie.de
 - Himmelsvorschau
 - Astronavigation
astronomie.info
MS WorldWide Telescope  |  webclient
Google Sky | Google Moon | Google Earth Sky
Celestia
Sloan Digital Sky Survey  |  SkyServer 
SpaceWeather
Astronomy Online
calsky - Astronomiekalender
 - Planetarium
Intl. Astronomical Union
Starkenburg-Sternwarte |  - IAU Sternwarten
Atlas of the Universe
ZDF Spacemodule

In the beginning the universe was created.

This has made a lot of people very angry and been widely regarded as a bad move.

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