- Galaxy (Wikipedia)
A galaxy is a system of stars, stellar remnants, interstellar gas, dust, and dark matter bound together by gravity. The word is derived from the Greek galaxias (γαλαξίας), literally ‘milky’, a reference to the Milky Way galaxy that contains the Solar System. Galaxies, averaging an estimated 100 million stars, range in size from dwarfs with less than a hundred million stars, to the largest galaxies known – supergiants with one hundred trillion stars, each orbiting its galaxy’s center of mass. Most of the mass in a typical galaxy is in the form of dark matter, with only a few percent of that mass visible in the form of stars and nebulae. Supermassive black holes are a common feature at the centres of galaxies.
- United States National Security Council (Wikipedia)
The United States National Security Council (NSC) is the principal forum used by the president of the United States for consideration of national security, military, and foreign policy matters. Based in the White House, it is part of the Executive Office of the President of the United States, and composed of senior national security advisors and Cabinet officials.