Chapter 1 The Nature Of Science Section 1 Science All Around Mysteries and Problems Scientists are much like detectives trying to solve a mystery. 1996- While looking through historical data, scientists found record of a tsunami that smashed the coast of the Island Honshu (The largest island of Japan). Problem: What caused the huge ocean waves? The Search for Answers Scientists suspected that it was an earthquake along the coast of North America. On the west coast there is a
subduction zone that runs from British Columbia Canada to northern California. It s called Cascadia. Subduction zone- where one section of Earth s crust (plate) slips underneath another section of crust. Gathering Evidence There did seem to be evidence off the coasts of Washington and Oregon where much of the coast had sunk killing thousands of trees. It would be hard to prove though that it happened at the same time. A Possible Solution One scientist who studied tree rings thought he knew how it could be dated. He made an educated guess called a hypothesis that tree rings in the drowned trees could be used to date the earthquake.
After two groups of scientists analyzed the trees, they found that something killed or damaged the trees between August 1699 and before spring of 1700. Importance of Solving the Mystery In addition to solving the mystery of what caused the tsunami, the tree rings also provided a warning for people living in the Pacific Northwest. There have been very large earthquakes there and it s only a matter of time before it happens again. Scientific Methods Scientific methods- problem solving procedures Includes: Identifying the problem gathering information
developing a hypothesis testing hypotheses analyzing results drawing conclusions Science Science means- having knowledge Science- is the process of observing, studying and thinking about things in your world to gain knowledge. Earth Science- is the study of Earth and space. Some topics include- rocks, minerals, soil, volcanoes, earthquakes, maps, fossils, mountains, climates, weather, ocean water, and objects in space Working in the Lab Experiments- must be carefully designed.
Validity- shows whether something is right or wrong Variables and Constants Variable- different factors in an experiment that can change Independent variable- variable that the scientist changes Constant- variable that does not change Dependant variable- variable being measured Control- standard to which results can be compared Repeating experiments- the more times you repeat and experiment the more reliable or valid your results will be.
Testing- Can begin when experiment procedures have been decided. You should observe while experimenting and carefully record data. After all data has been collected you should draw conclusions and analyze results. Also make sure to record any unexpected results. Technology- use of scientific discoveries for practical purposes. See pg 13 Using Technology Not all technology is complex. Technology is as simple as a ruler, a key, or a bandage. Transferable technology- technology from one situation can be applied to different situations. Example- material for spacecrafts are now
used in vehicles on Earth. Radar for military is now used for weather. 1.2 Scientific Enterprise A Work in Progress People have always been fearful or curious about things they don t understand. Some people relied on mythology to explain what they observed. The thought that mythological gods created storms, caused volcanoes to erupt etc. Recording Observations Some early civilizations recorded what they saw. The developed calendars around certain events. Example- Farmers in the Nile area knew it flooded every year right when the brightest
star Sirius appeared at dawn. Crops had to be planted at a certain time to avoid it. From this they developed a calendar with 365 days on it. The History of Meteorology Meteorology- study of weather Weather Instruments Earliest- measured amount of rain on a ruler from India 321-296 BC 1600 s- Italian scientists developed a more extensive measure including: barometer- measures air pressure thermometer- measures temperatures hygrometer- measures amount of water vapor in the air
anemometer- measures wind speed With these instruments weather stations were set up all over Italy. Weather Prediction in the United States Benjamin Franklin- 1 st American to say weather could be predicted. He said storms generally move from west to east and that storms could be monitored and those in the path of the storm could be notified. This began being practiced in 1837 when the telegraph machine was invented. By 1849- volunteers sent weather by telegraph to the Smithsonian Institution. In 1850 Joseph Henry, secretary of the Smithsonian made a huge weather map which displayed weather, and a forecast was sent out to the Washington Evening Post to be published.
National Weather Service Late 1800 s- United States Weather Bureau had more than 350 observing sites 1923- forecasts were carried by 140 radio stations. 1970- USWB was changed to the National Oceanic and Atmospheric Administration (NOAA) Today- we use satellites, weather balloons, and radars. Over 600,000 reports are sent in. Continuing Research Scientific Knowledge changes as scientists develop better instruments and testing procedures. As it changes scientists have a better understanding of nature.
Scientific Theories Scientific theory- explanation or model backed by results obtained by tests or experiments. 1949- American Astronomer Fred Whipple said a comet was a nucleus of dust and ice and as it got close to the sun, the ice and was vaporized and it made a tail. This hypothesis was published in 1950 in Astrophysical Journal. Hypothesis Supported Before it became a theory, Whipple s hypothesis was tested many times. A group from the University of Arizona studied Haley s Comet in Arizona and Chile, South America. They also used data collected from spacecrafts. Eventually Whipple s hypothesis became a theory.
Scientific Law Scientific law- a rule that describes the behavior of something in nature. Usually it describes what will happen given a certain situation, but doesn t explain why. Example- Newton s 1 st law of motion, an object in motion or at rest tends to stay in motion or at rest until it s acted upon by an outside force. Newton s 2 nd Law- when a force is acted upon an object, that object will change speed, direction or both. Newton s 3 rd Law- for every action there is an equal and opposite reaction. Limits of Science Science can t explain everything because it
is limited to what it can observe, measure and test. Some things cannot be tested because it could be harmful. Ethics- deals with moral values and what is good or bad. Example- can t test on humans if it will harm them. Doing Science Right The correct way to do science is to perform experiments in a way that honestly tests hypotheses and draws conclusions in an unbiased way. Being Objective Tests in science must be done objectively, or without bias. Bias- personal opinion
1940 s Trofim Lysenko- thought that trees of the same kind would not compete against each other, just other species for nutrients and water. Thought was based on how the Soviet Union was run at the time. Many of the trees died. Being Ethical and Open People who perform science in an ethical, unbiased way use only data and observation to draw conclusions. They also report this information in a detailed manner so it can repeated. Fraud- dishonest acts or statements to show false results