Universe information

1. Reviewing the Universe Out of this World!

2. Out of this World! 1. The entire celestial cosmos (everything in space), an orderly and harmonious system, is known as the universe.

3. Big Bang Theory Out of this World!

8. Radiation Map of the Universe Astronomy probe 5-yr mission

12. Galaxy Formation Out of this World! Out of this World!

13. Out of this World! 5. Also, in the universe, there are billions and billions of stars .

15. Out of this World! 7. A star’s brightness is referred to as its magnitude . There are two ways to think about this:

18. Out of this World! 8. The most common (90%) kind of star in the universe is known as a main sequence star. Our sun is an example of this kind of star.

19. Out of this World! 9. Stars are “born” in a part of the universe called a nebula .

20. Out of this World! 10. As they age, several things can happen to stars. In the end, most stars grow to become red giants (or super giants if they are exceptionally massive.)

23. Out of this World! C. White dwarfs and eventually black dwarfs (what the least massive stars will become, like our sun)

24. Out of this World! 12. The more massive stars explode before they become neutron stars or black holes. This incredible sight is referred to as a supernova . This is a photograph of Supernova 1987 a, one of the only ever witnessed.

25. Out of this World! 13. The second closest star to us is called Alpha Centauri , which is 4.3 light years away. Although it appears as one bright light, it is actually three separate bodies! Here is how the three stars that make up Alpha Centauri compare to the sun.

26. Out of this World! Many stars are like this… when there are more than one “body” that we see as one light, the stars are called companions (because they go together). The Chandra image shows Mira A (right), a highly evolved red giant star, and Mira B (left), a white dwarf.

27. Out of this World! Two stars like this are called binary stars , the prefix bi- means “two” (like a bicycle). Mira (shown here) is an example of such a star system. The companion star to Mira is referred to as Omicron Ceti A.

30. Out of this World! Unfortunately, we can’t travel that fast (yet?), but if we could, Einstein thinks several changes would happen to us: a. We would become more massive. b. We would shrink in length. c. Time would pass slower . This is outlined in his Theory of Relativity , which explains how mass, distance, speed, and time are interrelated - a strange concept to think about! See an example of what Einstein means… http://www.pbs.org/wgbh/nova/einstein/hotsciencetwin/index.html

31. Out of this World! 15. People have studied the stars for thousands of years. In doing so, they have identified groups of stars that appear to form pictures in the sky. These are known as constellations . There are 88 identified constellations in all - most of which have some sort of story or myth associated with it.

32. Out of this World! 16. The North Star is always visible from our viewing point on earth; it is also known as Polaris (like the shopping mall).

33. Out of this World! 17. One of the most influential instruments (if not the most influential) in discovering what we know about the universe is the Hubble Telescope.