Observational data suggests that supermassive black holes may exist at the center of many, if not all, galaxies. They are proposed to be the primary cause of active galactic nuclei found at the core of some galaxies. The Milky Way galaxy appears to harbor at least one such object within its nucleus. A blue giant is a massive star that has exhausted the hydrogen fuel in its core and left the.

Scientific, historical and cultural facts about outer space, galaxies,. 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 the universe. Select a category from the menu or explore the images below to learn more.