Download The Stars

SCI 2201: Concepts in Science
Discussion Topic: The Stars Trefil and Hazen The Sciences Chapter 14
Big Idea: The Sun and other stars use nuclear fusion reactions to convert mass into energy.
Eventually, when a star’s nuclear fuel is depleted, it must burn out.
Central Question: What are the characteristics and developmental processes of the stars?
This discussion should help you to:
1. distinguish between a star and a planet.
2. define the term “light-year,” and indicate its importance in the astronomical
distance scale.
3. compare and contrast the function and design of different telescopes (refracting,
reflecting, radio).
4. describe the process by which the sun generates energy.
5. describe the internal structure of the sun.
6. define the solar wind, and indicate its effects on the planets.
7. describe three major types of stars (main sequence, supergiants, white dwarfs) in a
stellar cycle.
8. interpret a Hertzsprung-Russell Diagram
9. distinguish between nova, supernova, neutron star and black hole.
Science Literacy Benchmarks (AAAS, 1993, 4.A: The Physical Setting)
By the end of the 2nd grade, students should know that
 There are more stars in the sky than anyone can easily count, but they are not scattered
evenly, and they are not all the same in brightness or color.
By the end of the 5th grade, students should know that
 The patterns of stars in the sky stay the same, although they appear to move across the
sky nightly, and different stars can be seen in different seasons.
 Telescopes magnify the appearance of some distant objects in the sky, including the
moon and the planets. The number of stars that can be seen through telescopes is
dramatically greater than can be seen by the unaided eye.
 Planets change their positions against the background of stars.
 Stars are like the sun, some being smaller and some larger, but so far away that they look
like points of light.
By the end of the 5th grade, students should know that
 The sun is a medium-sized star located near the edge of a disk-shaped galaxy of stars,
part of which can be seen as a glowing band of light that spans the sky on a very clear
night. The universe contains many billions of galaxies, and each galaxy contains many
billions of stars. To the naked eye, even the closest of these galaxies is no more than a
dim, fuzzy spot.
 The sun is many thousands of times closer to the earth than any other star. Light from the
sun takes a few minutes to reach the earth, but light from the next nearest star takes a few
years to arrive. The trip to that star would take the fastest rocket thousands of years.
Some distant galaxies are so far away that their light takes several billion years to reach
the earth. People on earth, therefore, see them as they were that long ago in the past.