STARS AND GALAXIES
UNIT GOALS: After completing this unit, the students will:
GRADE LEVEL: (9-12)
- understand what stars and galaxies are
- how gravity holds them together
- how stars and galaxies move and change with time
- gain some appreciation for the enormous size of both space and time that these objects occupy.
MINIMUM TIME REQUIRED FOR THE UNIT: 10 instructional days (50 minute periods)
CONCEPTS LEARNED ACROSS ALL UNIT MODULES:
STANDARDS ADDRESSED BY UNIT MODULES:
- Distance, scales and ratios
- Star brightness, lifetime and color
- Star mass and life stages
- Galaxy classification
- Energy source of galaxies
- Galactic evolution
AAAS Project 2061 Benchmarks:
- The stars differ from each other in size, temperature, and age, but they appear to be made up of the same elements that are found on the earth and to behave according to the same physical principles. Unlike the sun, most stars are in systems of two or more stars orbiting around one another. (4A, Grades 9-12)
- On the basis of scientific evidence, the universe is estimated to be over ten billion years old. The current theory is that its entire contents expanded explosively from a hot, dense, chaotic mass. Stars condensed by gravity out of clouds of molecules of the lightest elements until nuclear fusion of the light elements into heavier ones began to occur. Fusion released great amounts of energy over millions of years. Eventually, some stars exploded, producing clouds of heavy elements from which other stars and planets could later condense. The process of star formation and destruction continues. (4A, Grades 9-12)
- Increasingly sophisticated technology is used to learn about the universe. Visual, radio, and x-ray telescopes collect information from across the entire spectrum of electromagnetic waves; computers handle an avalanche of data and increasingly complicated computations to interpret them; space probes send back data and materials from the remote parts of the solar system; and accelerators give subatomic particles energies that simulate conditions in the stars and in the early history of the universe before stars formed. (4A, Grades 9-12)
- Mathematical models and computer simulations are used in studying evidence from many sources in order to form a scientific account of the universe. (4A, Grades 9-12)
National Science Education Standards (Content Standard A, Grades 9-12)
- The origin of the universe remains one of the greatest questions in science.
- Billions of galaxies, each of which is a gravitationally bound cluster of billions of stars, now form most of the visible mass in the universe.
- Stars produce energy from nuclear reactions, primarily the fusion of hydrogen to form helium. These and other processes in stars have led to the formation of all the other elements.
Maryland State Department of Education High School Science Core Learning Goals
TECHNOLOGY NEEDED IN UNIT MODULES:
- The student will use a variety of resources to identify techniques used to investigate Earth and the Universe.
- The student will explain the role of natural forces in the formation of galaxies.
- The student will know how to use measurements of different orders of magnitude to construct an earth science model.
TECHNOLOGY-ENHANCED INSTRUCTIONAL STRATEGIES EMPLOYED:
- Internet access for individuals or small groups, Microsoft PowerPoint, GalaxSee software.
TITLE OF EACH MODULE:
UNIT CULMINATING ACTIVITY:
- Image presentation
- Parallel-Problem Solving
- Computer Simulation
- Web-based Research