1.1b classification of galaxies
- 1. Classification of GalaxiesChapter 16.1b
- 2. ACHIEVEActivity – Direct InstructionConversation – Voice Level 2. Limit to topic.Help – Raise hand until recognized. Integrity – If you go behind in note taking, raise your hand and ask for a “repeat or slow down.”Effort – Sit up eyes on screen, handout, or your notes. Write notes about material presented.Value – Presentation will help you more fully understand Galaxy Classificaton.Efficiency – Glue handouts and notes in notebook for easy access.
- 3. ExpectationWrite down things on your notebook starting from the next available space.Poster will be turned in today.
- 4. Classification of GalaxiesIrregular GalaxiesElliptical GalaxiesSpiral Galaxies
- 5. Irregular GalaxiesIrregular galaxies have no regular or symmetrical structure. They have regions of elemental hydrogen gas, and many young stars. They have large amounts of dusts from which stars are born.
- 10. Spiral GalaxiesSpiral galaxies have three main components: a central bulge, disk, and halo
- 11. Spiral GalaxiesThe bulge is a spherical structure found in the center of the galaxy. This feature mostly contains older stars.
- 12. Spiral GalaxiesThe disk is made up of dust, gas, and younger stars. The disk forms arm structures. Our Sun is located in an arm of our galaxy, the Milky Way.
- 13. Spiral GalaxiesThe halo of a galaxy is a loose, spherical structure located around the bulge and some of the disk. The halo contains old clusters of stars, known as globular clusters.
- 14. Spiral GalaxiesGlobular clusters are spherical concentrations of stars typically 100 light years across and containing thousands of stars. Globular clusters 10 billion years oldformed when the galaxy was still forming.
- 15. Spiral Galaxies
- 16. Spiral Galaxies
- 17. Spiral Galaxies
- 18. Spiral Galaxies
- 19. Elliptical GalaxiesElliptical galaxies are shaped like an elongated sphere.The light is smoothThe surface brightness decreases as you go farther out from the center.Elliptical galaxies have no particular axis of rotation.