1. all existing matter and space considered as a whole; the cosmos believed to be at least 10 billion light years in diameter and contain a vast number of galaxies has been expanding since its creation expansion believed to be result of a violent, powerful explosion 13.7 billion years ago (Big Bang) Week 7 Day 1 The Universe

2. Quasar=a distant energy source which gives off vast amounts of radiation, including radio waves and X-rays ----believed by many scientist to be most distant objects in universe ------can be a trillion times brighter than the sun ------believed to produce their energy from massive black holes in the center of galaxies where the quasar is located -------drown out the light from all other stars in the same galaxy because of brightness The Universe

3. Black Hole=the leftover core of a super massive star after a supernova ------exert tremendous gravitational pull ------very dense -----Scientist believe the fuel for a black hole is the trapped gas, stars, and dust that are pulled into the hole. ------the speed of the gas swirling into the black hole gives it a signature. -------mass is calculated if speed of swirling gas is known The Universe

4. Dark Matter= composed of particles that do not absorb, reflect, or emit light -----cannot be detected by observing electromagnetic radiation ----material that cannot be seen directly ------initially called “missing matter” because astronomers could not find it by observing the universe in any part of the electromagnetic spectrum Satellites are being used to gather dark matter data. Week 7 Day 2 The Universe

5. Dark Matter= matter that cannot be detected but is believed to give galaxies the extra mass, generating the extra gravity they need to stay intact -----does not interact with the electromagnetic force -----does not absorb, reflect or emit light ------scientist have only been able to infer its existence from the gravitational effect on visible matter -----27 % of Universe The Universe

6. Dark Energy=an unknown form of energy which is hypothesized to permeate all of space, tending to accelerate the expansion of the universe ----68 % of Universe ------Other than the % fact, NASA says that it is a complete mystery Week 7 Day 2 The Universe