Date post: | 17-Jul-2015 |
Category: |
Science |
Upload: | kristel-joy-jadormio |
View: | 46 times |
Download: | 1 times |
What does it consist?
Milky Way-“Galaxies kuklos”
Galileo -Numerous stars
18th century-William and Caroline Herschel
- Mapped the distances of stars
1781-Charles Messier
- Cataloged various nebulae
20th century-Harlow Shapely
- Measures the distributions and locations of globular star clusters.
1924- Edwin Hubble
-Resolved that the spiral nebulae had structures and stars- CEPHEID VARIABLES.
II. FORMATION AND EVOLUTION
Ideas about the origins and evolutions:
• collapsing dust clouds = formation of galaxies
• collisions between galaxies
Two assumptions:
1. Filled with hydrogen and helium
2. Some areas were slightly denser than others
EARLY UNIVERSE THEORIES
Two factors:
• Angular momentum (degree of spin)
• Cooling
III. DISTRIBUTION OF GALAXIES
INTERGALACTIC MEDIUM
Space between galaxies and clusters of galaxies
THE DOPPLER EFFECT
Messier 32: a dwarf elliptical (E2) satellite galaxy of the Andromeda Galaxy
Messier 87: giant elliptical (E1) at the Virgo Cluster's core. It has grown very large by ``eating'' other galaxies.
NGC 2997: a large face-on spiral galaxy (Sc)
Messier 81: a large spiral galaxy (Sb).
The Triangulum Galaxy (=M 33): a small spiral galaxy (Scd) in the Local Group
NGC 1365: a barred spiral galaxy (SBbc)
NGC 3351 (=M 95): a barred spiral galaxy (SBb).
Messier 82: a starburst galaxy
V. PARTS OF A GALAXY