 In the past, early humans believed in mythology to try to explain what they observed.  What is mythology?  What were some occurrences people may have been afraid?

 Ancient civilizations believed their gods controlled the weather.  Early civilizations recorded what they observed: ◦ Recorded calendars which described natural reoccurring phenomena.  Egyptians ◦ Nile river flooded crops every year ◦ Shorty before the flood, the brightest star Sirius appeared at dawn in the east. ◦ The Egyptian calendar was created.  Instruments were created to help aid in answers.

 Meteorology – The study of weather.  The history of meteorology illustrates how the understanding of weather has developed over time.

 Rain gauge – probably first weather instrument used to measure the amount of rainfall. (321 B.C. – 296 B.C.)  Barometer – used to measure air pressure.  Thermometer – used to measure temperature.

 Hygrometer – used to measure water vapor in the air.  Anemometer – used to measure wind speed.

 Benjamin Franklin was the first American to suggest that weather could be predicted through observation.  Joseph Henry was able to draw maps which included weather data.

 National Oceanic Atmospheric Administration (NOAA) ◦ The National Oceanic and Atmospheric Administration (NOAA) is a federal agency focused on the condition of the oceans and the atmosphere.  Orbiting satellites  Weather balloons  Radio, television, media

 Technology is continuously being enhanced everyday.

 A scientific theory is an explanation or model backed up by results obtained from many tests or experiments.  Many scientist work together to develop a theory.  Most logical explanation of why things work.  A theory can be revised with new information. ◦ Example: Comets – Dr. Fred L. Whipple hypothesized that a comet was similar to a dirty snowball. The n nucleus of the comet contains most of its mass.

 A scientific law is a statement about what usually happens in nature and that seems to be true all of the time. ◦ Ex. Newton’s first law of motion  An object in motion will stay in motion unless an unbalanced force acts on it. An object at rest will stay at rest unless an unbalanced force acts on it.  Laws can be used to predict what will happen in a given situation, however they don’t explain why.  Laws may also be revi.sed if new observations show them to be incorrect

 Science does not always provide an answer to your question.  In science you need variables which need to be observed, measured and tested.  Problems with belief systems and ethics cannot be answered using these methods. ◦ Ethics deals with the moral values about what is good and what is bad.

 How can we be ethical in science?

 When performing an experiment it is important never to be bias.  Bias is a personal opinion which can effect your observations and outcome.  Turn to page 21 in your textbook.

 It is important to keep detailed records of your experiment.  Your conclusion should be based on precise measurements and test.