December 8-14, 2011, Current Events Lesson Plan
Current Event:
A black hole recently found by scientists is so monstrous that it dwarfs any black hole found before. Located about 335 million light-years from Earth, the black hole has at least 20 billion times as much mass as the sun. It is also 2,000 times as massive as the black hole that resides in the center of our galaxy, the Milky Way Galaxy. The previous record-holder among black holes is 6.7 billion times as massive as the sun.
Objective:
A black hole is a region of space whose gravitation is so strong that nothing can escape from it–not even light. The Behind the Headlines news story and related World Book articles will help to explain the characteristics of a black hole and how scientists measure their size.
Vocabulary Terms:
Discussion Topics:
1. The larger of the two black holes scientists recently found is located about 335 million light-years from Earth. A light-year is a unit used by astronomers to measure the great distances between objects in the universe. It is the distance that light travels in a vacuum in one year. Play a “higher or lower” guessing game with your students to first teach them how many miles or kilometers are equal to one light-year, and then how many light-years away the newly discovered black hole is. Ask students one by one to guess the distance and respond by saying “higher” or “lower” until one student guesses the correct answer.
Speed of light =
- One light-year = 5.88 trillion miles/9.46 trillion kilometers
- The newly discovered black hole = 335 million light-years from Earth
2. Scientists estimated that the larger of the newly discovered black holes has at least 20 billion times as much mass as the sun. The previous record-holder among black holes is 6.7 billion times as massive as the sun. Discuss the concepts of mass and matter and how they relate to each other. Explain to students that weight is a measure of the gravitational pull on an object. Objects with greater mass have a greater gravitational pull. In commercial and everyday use, weight is understood to mean mass. Ask students to find the mass of several objects by weighing them and then report their findings.
3. Black holes are invisible because they trap even light. Ask your students to hypothesize how one could find, let alone measure, an invisible object in space? Then explain to them that scientists first thought black holes could exist based on equations in the theory of general relativity developed by German-born physicist Albert Einstein. One way astronomers discover black holes is by detecting the X rays and radio waves given off when gas and other matter are pulled into a black hole. Another way is by observing the movement of stars around a suspected black hole. Astronomers at the University of California, Berkeley, measured the mass of the black holes by clocking the speeds at which stars orbit (revolve around) them. The faster the stars orbit, the greater the mass of a black hole required to keep the stars from being flung into space.
4. Use World Book’s timeline feature to view the highlights of science from as far back as the 400′s B.C. Or, ask your students to create their own astronomy-related timelines.