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.Research Case StudiesBelow are some case studies of scientists who made significant sci-entific breakthroughs. You will see how scientific research leads to more scientific research, and that theories must be tested and modi-fied in order to better understand our universe.

Case Study 1:Many theories have tried to explain the formation of lightning, but the predictions of these theories have failed to account for the data. C. T. R. Wilson theorized in 1925 that lightning formed when cos-mic rays from the sun collided with air molecules to form unstable molecules, which, in turn, produced electrons. However, the amount of electrons predicted by this model failed to produce the electrical energy needed to create lightning.

Alexander V. Gurevich theorized in 1961 that lightning formed when electrons escaped from an incredibly strong electrical field. However, the strength of the electrical field necessary to create this effect is many times stronger than what is observed in thunderclouds. In 1992, Gurevich teamed up with two Americans, Gennady M. Mi-likh and Robert Roussel-Dupré, to propose a new theory called the Relativistic Runaway Electron Avalanche (RREA) model. This model suggests that runaway free electrons bump into air molecules, which produce more runaway free electrons, in an avalanche-like fashion. Gurevich, Milikh, and Roussel-Dupré proposed that this model fits the data because the avalanche starts with only a few electrons, which can be created from cosmic rays within a reasonable electrical field, like the ones observed in thunderclouds. These electrons have the potential to produce voltages strong enough to travel through the air, much like the sparks that you observe when you shuffle your feet across a carpet and reach for a doorknob.

But how do you experiment with lightning? In Florida, where lightning strikes are a very common occurrence, a laboratory called the International Center for Lightning Research and Testing (ICLRT) has been set up. It contains equipment to trigger lightning in thunderstorms by firing rockets into naturally occurring thun-derclouds. Sensitive, protected instruments on the ground measure any emissions from the lightning bolts or thunderclouds overhead. The RREA model predicts that runaway electrons will turn neutral air molecules into charged molecules called ions, also producing x-rays and gamma rays as a byproduct. If the RREA model is cor-rect, then x-rays and gamma rays should be observed near lightning bolts. Scientific American’s article, “A Bolt out of the Blue” (May 2005), documents Joseph Dwyer’s experimentation with lightning at ICLRT and his findings of strong x-rays and gamma rays emit-ted from thunderclouds that can be sensed from the ground. Despite these findings, the process of lightning formation still leaves many unanswered questions.

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Case Study 2:On July 4, 2005, NASA’s Deep Impact mission accomplished its pur-pose: its impactor collided with Comet Tempel 1, creating a crater 6 km in diameter and releasing tons of cometary debris into space. Mi-chael A’Hearn, the principal investigator of the mission, and his team designed this mission to find out about the components of the early solar system, from which comets are thought to be a relic. The composition of the comet revealed by the impact could give clues to the formation of our solar system and the beginning of life on Earth. Evolutionists believe that a comet might have brought the necessary building blocks for life to Earth. Earth-based telescopes, the Hubble Space Telescope, and the Deep Impact flyby spacecraft all captured stunning images of the impact of the probe and the comet.

Astronomers had long regarded the dirty snowball model of a comet to be the prevailing thought about the composition of comets. This model states that comets are simply dust and rock held together with ice. Comet Tempel 1 proved to have a very different composi-tion than scientists predicted. They found that it consisted of very fine dust particles and much less water than had been anticipated. Hot bursts of water vapor and carbon dioxide were emitted first from the collision. Scientists are still analyzing images and measurements taken from the impact.

Case Study 3:One of the pioneering fields of science is known as nanotechnology—science on the scale of one billionth of a meter. Carbon atoms, which are used extensively in nanotechnology, can be linked to form many different substances, like graphite, coal, diamond, and a soccerball-shaped molecule called buckminsterfullerene. In 1991, Sumio Iijima discovered nanotubes, which form by linking carbon atoms or other atoms to form tubes only a few nanometers in diameter, or 0.00002 times the thickness of a human hair. But these tubes behave very dif-ferently based on their size and shape. Models predicted how water would behave inside a nanotube, but in a paper published in July 2004, Alexander Kolesnikov and his research group found that water in a nanotube will not freeze, even at temperatures of 8 K (–445 °F)! This water behaved differently from bulk liquid water and solid water (ice); it tended to flow more freely than expected. While some water molecules link to form a tube of ice just inside the nanotube wall, other water molecules continue to flow. The team has com-mitted to refine the model of nanotube water behavior and to try to empirically determine its properties. Paradoxically, other research-ers found that the tubular ice just inside the wall of the nanotubes will remain in its solid phase up to room temperature, even at subat-mospheric pressures.

Michael A’Hearn is professor of astronomy at the University of Maryland and is the principal investigator of the Deep Impact mission as well as NASA’s planetary data system of small bodies in our solar system. In fact, he has an asteroid named after him.

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Case Study 4:A group working in the Lao People’s Democratic Republic on a biodi-versity project in the Khammouan province discovered an interest-ing rodent that locals referred to as the kha-nyou in the village food market. The group sent skeletal specimens to the National Museum of History in London. The rat-like rodent, commonly called a rat-squirrel, was discovered to be a new mammal and has been named Laonastes aenigmamus. DNA tests are currently being performed on samples from the new mammal to determine how it will fit into the Linnaean classification system. The discoverers proposed that it represented a brand new family, Laonastidae. This new finding was published in the scientific journal, Systematics and Biodiversity, in December 2004. After the publication of this finding, phylogenists disputed the creation of a new family and proposed instead that it is part of the existing family Diatomyidae. This is a family known only from the fossil record, making this newly discovered rodent part of a Lazarus taxon, one that has come back from the dead!

Case Study Review Questions 1. Look at the case studies. Did any of them follow the scientific

method? If so, which ones? How can a scientific study be valid if it does not follow the scientific method?

2. Name a few of the qualities that the case studies have in common. What can you deduce about the scientific process from these qualities?

3. Read case study 1 again. What was the scientific problem? How was the problem resolved?

4. Look at case study 2. How do you think Dr. A’Hearn’s worldview directed his scientific research, and how could it influence his interpretation of the data that he gathered?

5. Although it is not explicitly mentioned in case study 3, why is the use of models in nanotechnology essential?

6. What does case study 4 imply about the scientific process? 7. What does the controversy surrounding the family designation

of Laonastes aenigmamus tell you about the nature of organism classification?

3 Foundations of Chemistry

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.Research Case StudiesBelow are some case studies of scientists who made significant sci-entific breakthroughs. You will see how scientific research leads to more scientific research, and that theories must be tested and modi-fied in order to better understand our universe.

Case Study 1:Many theories have tried to explain the formation of lightning, but the predictions of these theories have failed to account for the data. C. T. R. Wilson theorized in 1925 that lightning formed when cos-mic rays from the sun collided with air molecules to form unstable molecules, which, in turn, produced electrons. However, the amount of electrons predicted by this model failed to produce the electrical energy needed to create lightning.

Alexander V. Gurevich theorized in 1961 that lightning formed when electrons escaped from an incredibly strong electrical field. However, the strength of the electrical field necessary to create this effect is many times stronger than what is observed in thunderclouds. In 1992, Gurevich teamed up with two Americans, Gennady M. Mi-likh and Robert Roussel-Dupré, to propose a new theory called the Relativistic Runaway Electron Avalanche (RREA) model. This model suggests that runaway free electrons bump into air molecules, which produce more runaway free electrons, in an avalanche-like fashion. Gurevich, Milikh, and Roussel-Dupré proposed that this model fits the data because the avalanche starts with only a few electrons, which can be created from cosmic rays within a reasonable electrical field, like the ones observed in thunderclouds. These electrons have the potential to produce voltages strong enough to travel through the air, much like the sparks that you observe when you shuffle your feet across a carpet and reach for a doorknob.

But how do you experiment with lightning? In Florida, where lightning strikes are a very common occurrence, a laboratory called the International Center for Lightning Research and Testing (ICLRT) has been set up. It contains equipment to trigger lightning in thunderstorms by firing rockets into naturally occurring thun-derclouds. Sensitive, protected instruments on the ground measure any emissions from the lightning bolts or thunderclouds overhead. The RREA model predicts that runaway electrons will turn neutral air molecules into charged molecules called ions, also producing x-rays and gamma rays as a byproduct. If the RREA model is cor-rect, then x-rays and gamma rays should be observed near lightning bolts. Scientific American’s article, “A Bolt out of the Blue” (May 2005), documents Joseph Dwyer’s experimentation with lightning at ICLRT and his findings of strong x-rays and gamma rays emit-ted from thunderclouds that can be sensed from the ground. Despite these findings, the process of lightning formation still leaves many unanswered questions.

1 Foundations of Chemistry

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Case Study 2:On July 4, 2005, NASA’s Deep Impact mission accomplished its pur-pose: its impactor collided with Comet Tempel 1, creating a crater 6 km in diameter and releasing tons of cometary debris into space. Mi-chael A’Hearn, the principal investigator of the mission, and his team designed this mission to find out about the components of the early solar system, from which comets are thought to be a relic. The composition of the comet revealed by the impact could give clues to the formation of our solar system and the beginning of life on Earth. Evolutionists believe that a comet might have brought the necessary building blocks for life to Earth. Earth-based telescopes, the Hubble Space Telescope, and the Deep Impact flyby spacecraft all captured stunning images of the impact of the probe and the comet.

Astronomers had long regarded the dirty snowball model of a comet to be the prevailing thought about the composition of comets. This model states that comets are simply dust and rock held together with ice. Comet Tempel 1 proved to have a very different composi-tion than scientists predicted. They found that it consisted of very fine dust particles and much less water than had been anticipated. Hot bursts of water vapor and carbon dioxide were emitted first from the collision. Scientists are still analyzing images and measurements taken from the impact.

Case Study 3:One of the pioneering fields of science is known as nanotechnology—science on the scale of one billionth of a meter. Carbon atoms, which are used extensively in nanotechnology, can be linked to form many different substances, like graphite, coal, diamond, and a soccerball-shaped molecule called buckminsterfullerene. In 1991, Sumio Iijima discovered nanotubes, which form by linking carbon atoms or other atoms to form tubes only a few nanometers in diameter, or 0.00002 times the thickness of a human hair. But these tubes behave very dif-ferently based on their size and shape. Models predicted how water would behave inside a nanotube, but in a paper published in July 2004, Alexander Kolesnikov and his research group found that water in a nanotube will not freeze, even at temperatures of 8 K (–445 °F)! This water behaved differently from bulk liquid water and solid water (ice); it tended to flow more freely than expected. While some water molecules link to form a tube of ice just inside the nanotube wall, other water molecules continue to flow. The team has com-mitted to refine the model of nanotube water behavior and to try to empirically determine its properties. Paradoxically, other research-ers found that the tubular ice just inside the wall of the nanotubes will remain in its solid phase up to room temperature, even at subat-mospheric pressures.

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Michael A’Hearn is professor of astronomy at the University of Maryland and is the principal investigator of the Deep Impact mission as well as NASA’s planetary data system of small bodies in our solar system. In fact, he has an asteroid named after him.

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Case Study 4:A group working in the Lao People’s Democratic Republic on a biodi-versity project in the Khammouan province discovered an interest-ing rodent that locals referred to as the kha-nyou in the village food market. The group sent skeletal specimens to the National Museum of History in London. The rat-like rodent, commonly called a rat-squirrel, was discovered to be a new mammal and has been named Laonastes aenigmamus. DNA tests are currently being performed on samples from the new mammal to determine how it will fit into the Linnaean classification system. The discoverers proposed that it represented a brand new family, Laonastidae. This new finding was published in the scientific journal, Systematics and Biodiversity, in December 2004. After the publication of this finding, phylogenists disputed the creation of a new family and proposed instead that it is part of the existing family Diatomyidae. This is a family known only from the fossil record, making this newly discovered rodent part of a Lazarus taxon, one that has come back from the dead!

Case Study Review Questions 1. Look at the case studies. Did any of them follow the scientific

method? If so, which ones? How can a scientific study be valid if it does not follow the scientific method?

The first two case studies on lightning and the Deep Impact mission followed the scientific method. Both of the other case studies involved truly scientific endeavors even though they did not follow the scientific method. They engaged in the scientific process and made scientific breakthroughs.

2. Name a few of the qualities that the case studies have in common. What can you deduce about the scientific process from these qualities?

Scientific finds often stimulate more scientific research because current models are shown to be inadequate, and more observation is required to refine the model to explain the aberrant data. The nature of the scientific process is one of constant refinement in our understanding of concepts that we consider fundamental, like the law of gravity and the laws of motion.

3. Read case study 1 again. What was the scientific problem? How was the problem resolved?

The purpose of Joseph Dwyer’s work was to confirm or disprove the RREA model of lightning formation. The problem was resolved by his conducting a controlled experiment.

4. Look at case study 2. How do you think Dr. A’Hearn’s worldview directed his scientific research, and how could it influence his interpretation of the data that he gathered?

Dr. A’Hearn obviously holds to the big bang model of the universe, and this presupposition affected how he viewed the origin and composition of comets. Creationists believe it is probable that comets and planets and stars all have the same age since they were all created on Day 4 of the Creation week. Acceptance of

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the big bang model is a presupposition that may affect how he interprets the data because he is assuming that the composition of comets may give a clue to the composition of the early earth and the processes that formed the planets.

5. Although it is not explicitly mentioned in case study 3, why is the use of models in nanotechnology essential?

Nanotechnology involves investigation that lies beyond humans’ ability to directly observe, even with sophisticated instrumenta-tion. (§1.11)

6. What does case study 4 imply about the scientific process? Sometimes scientific breakthroughs are simply serendipitous, a

matter of chance. The biodiversity team in Laos simply stumbled across a new finding.

7. What does the controversy surrounding the family designation of Laonastes aenigmamus tell you about the nature of organism classification?

Like most of science, it is in a constant state of change. Choices in classification (systematics) are based on which characteristics or measurements you deem significant. Artificial classification schemes based on genetic data often look very different from traditional natural schemes based on morphology.

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