Skepticism in the classroom

Yesterday, I posted a quote from David Suzuki on my facebook group about science education failing to incorporate skepticism. This was shared widely and approvingly reposed by several highly followed pages.

If you are a science educator yourself, you probably responded to this quote by saying something like "that is easy for you to say. I have tried to teach critical thinking and it is very hard to find material that I could actually use in my classroom."

I take this complaint very seriously. It is difficult to find good critical thinking materials that are both interesting and can actually be applied in the real world. Another reasonable requirement is that these resources need to be very affordable or free. This is because, at least in the United States, good educators get paid just as poorly as bad educators. Even if they are phenomenal science teachers, they simply do not have the extra money available to buy a bunch of stuff. Fortunately for us, many skeptical educators have already anticipated your concerns and have gone through the trouble of creating free skeptical resources for the classroom. These booklets and videos investigate fascinating topics and are tailored for children and young adults who need a dose of critical thinking added to their school curriculum and can can be downloaded with the click of a button.

The first resource that you should check out is a series of short pamphlets/books created by the James Randi Education Foundation. All three of these guides are custom made with certain age groups in mind (one is for elementary, one for late middle school, and one for high school) and are about non-threatening topics like dowsing, ESP, and faeries (Sir Arthur Conan Doyle, the writer of Sherlock Holmes believed in them). The JREF has provided both student and teacher editions so that you have all the material you need to lead a class discussion.  

If this sounds interesting, please click here and download them.

 

The second resource that I recommend is Brian Dunning's movie, Here be Dragons. This movie is designed to be watched in one class period (it is 45 minutes) and covers very interesting material like conspiracy theories and homeopathy. Mr. Dunning does an excellent job of outlining logical fallacies and exposing many of the bunk that hucksters without being threatening. He also explains how certain features of science work, why people believe in weird things, and even provides an excellent reading list at the end for students who want to know more. 

 

If Mr. Dunning's movie sounds appealing, you can get it here for free. 

 

Third, I want you to check out this workshop on instituting skepticism in the classroom. It was conducted at TAM 9 (The Amazing Meeting, which is a skeptical conference held by the JREF each year) and was later posted on the web. It includes lots of goodies including advice for teachers and several activities that can easily be incorporated into a lesson plan. In one of the most interesting of these activities, your students will get to see how astrology fools our brains. This is a valuable because realizing you can be easily fooled is the first step to becoming a skeptic. 

 

If you want to see these resourced, they have been made available here. 

 

Finally, I want you to check out these lessons created by the Leonore Annenburg Institute for Civics. While the institute's name may not sound skeptical, their lessons are some of the best available. They teach everything from how to examine popular claims to how our biases lead is to distorted conclusions. Given the nature of their material, they could just as easily be included into a civics or history class.

 

If this sounds appealing to you, click here to get these lessons.  

Hopefully these free resources serve you well in your classroom. In my opinion, they are all excellent and (if I had one) I put my seal of approval on them. If you are teaching your child critical thinking at home and feel left out, keep paying attention to my blog because I will be posting a list of affordable children's books that teach skepticism very soon. In the meantime, I recommend you incorporating these lessons at home.

 

Why Pluto is not a planet

While I was taking my first college level astronomy course, a rare event occurred. The International Astronomy Union voted to demote Pluto from planethood and assigned it the title of dwarf planet. My professor, being the excellent educator that she is, decided to use this demotion as an opportunity to educate the class. For the following two weeks, we were required to research why this demotion took place and then debate the cogency of the decision (if you teach astronomy, I suggest you do the same). Given that my class overwhelmingly consisted of Americans that grew up in the 1990's, almost no one saw the IAU's decision as a wise move. Our debate consisted of angry statements like: "This isn't right, everyone knows there are nine planets." "Tombaugh (Pluto's discoverer) was an American and so is Pluto."

If you were also seething mad at the IAU's decision to demote Pluto, I want you to think about a couple of things to calm your nerves. First, you need to understand that Pluto is still orbiting the Sun. NASA did not nuke it out the sky or send a giant boot to kick it out of the solar system. It is still made out of ice and rock and has a disproportionately large moon named Charon. The spacecraft New Horizons is also still due to to explore and photograph it in 2015. None of this has changed. All that has changed is Pluto is now grouped with a set of icy objects that are much more similar to it than any of the classical planets. That is it.

Second, you need to understand that this is not the first time that an object has been demoted from planethood. At the dawn of the 19th century, an Italian priest and astronomer named Giuseppe Piazzi (1746-1826) discovered a planet between Jupiter and Saturn. This object, which is named Ceres, was considered a planet for 50 years. It was eventually demoted, however, when it was discovered that Ceres was one body in a vast field of objects. These objects, now know as asteroids, were not known about before because of telescope limitations. Once the existence of countless asteroids were discovered, Ceres was demoted to being an asteroid and grouped in with them. Pluto's demotion, as we will discuss in a second, is strikingly similar to Ceres'.

Now that we understand that Pluto is still part of our Solar System and that Planetary regrouping has happened before, we can consider the reasons why I took the position in my class that Pluto is not a planet. The crux of my case focused around the history of the definition of planet. While it may sound odd, there was no formal definition of planet before the IAU's 2006 decision. Before we get to their definition, however, it will help us if we consider how the term planet has been informally used throughout the ages.

The shifting planets

In the ancient and medieval world, the word "planet" simply referred to those bodies in the sky that moved (the word itself comes from aster planetes, which is Greek for wandering star). Since the Greeks were predominantly geocentrists, they believed that there were seven planets (Mercury, Venus, Mars, Jupiter, Saturn, the Moon, and the Sun). This number was modified after geocentrism came under heavy attack by Copernicus, Kepler, and Galileo at the end of the Middle Ages. These men argued that the Earth was a planet and the Sun and Moon were not. By the time that Newton laid down his ideas on mechanics (the mid-late 17th century), the solar system was accepted to be six planets (Mercury, Venus, Earth, Mars, Jupiter, Saturn) orbiting the Sun.

The solar system started to change again when, in 1781, William Herschel discovered the first planet not known to the ancients: Uranus (pronounced your-in-is). The orbit of Uranus, however, caused astronomers many headaches. Unlike the other known planets, it did not conform to the path predicted by Newton's mechanics. To explain this anomaly, astronomers predicted that there was another planet even further out who was tugging on Uranus. Scientists finally found the culprit in 1846 when Neptune was discovered. While this solved much of the problems about Uranus' orbit, it unfortunately opened up another mystery. Much like Uranus, Neptune's orbit deviated from what it was expected to be via Newtonian mechanics. To explain this discrepancy, an even further out planet was postulated.

This planet was discovered in 1930 by the American Clyde Tombaugh. When Mr. Tombaugh discovered Pluto, it was believed to be much large than it actually is (the size of Earth)  It is also worth noting that, like Ceres, none of the objects surrounding Pluto were known at the time of its discovery. 

The case against Pluto

Now that we understand that the solar system has shifted around when new evidence emerges, my case focuses on Pluto's characteristics and the new formal definition of "planet." As I mentioned a second ago, Pluto is now known to be part of a collection of objects called TNO's (trans-Neptunian Objects). These objects are made of rock and ice and reside in a big belt past Neptune. It is helpful to think of them as a much bigger, further out asteroid belt.

the dots are the TNO's

This factor is important for two reasons: (1) like Ceres, Pluto has much more in common with these non-planetary objects than it does with any of the classical planets and (2) the IAU's drafted definition of "planet" includes a requirement that Pluto is unable to meet because of its TNO neighbors. Since we have explored what it historically meant to be a planet, we are now ready to ponder this definition:

The definition that the IAU drafted has three parts:

1. A planet must orbit its star.
2. A planet must be massive enough to be round.
3. A planet must clear its neighborhood.

Number (3) is the requirement that Pluto fails. But what does it mean to "clear its neighborhood?" This simply means that the object must contain the majority of the mass in its orbital path. For example, Earth is by far the most massive object in its path around the Sun. Pluto, on the other hand, has a minority of the mass in its orbital path. This is because of the large amount of icy and rocky debris around it due to its TNO neighbors. Since all of the 8 classical planets clear their neighborhood and Pluto does not, it is disqualified from being a planet.

There are also three more factors that weigh significantly against Pluto.

1. Pluto is not even a unique for a TNO. We now know that there are several other sizable objects in this area. The most notable is Eris, which is actually 1/5 more massive than Pluto. 
2. Pluto's orbit is tiled 17 degrees.  This cannot be said about the classical planets who orbit elliptically on a relatively flat plane.
3. Unlike any of the classical planets, Pluto and its moon both orbit a common center of gravity. This makes them a binary system. 

Simply put, Pluto just does not have that much in common with the eight planets. It also has a lot in common with the other "dwarf planets." To me, this along with the new evidence about the existence of TNO's (especially the larger Eris) means that the the IAU was correct in their decision to demote Pluto. This new label is also pedagogically sensible and makes it much easier to teach planetary science to children. Like introducing the label of "asteroid" and "comet", introducing "dwarf planet" prevented us from having too many small planets and it cleaned up our textbooks. 

If you have any doubt about my argument, I have a thought experiment for you. Imagine that Pluto was discovered today at the same time as all of the rest of the TNO's. Also imagine if, unlike Tombaugh, you knew its correct size. Would you consider it and its many friends as planets? I do not think so. 

In closing, I have one final remark. Many people love to anthropomorphize Pluto and pretend that its feelings were hurt when it was demoted. If you must make Pluto feel, I advise a small change. Instead of imagining it sad, I think you should imagine it as being much happier with its new set of friends than being the "odd man out" and a planet. This is because Pluto is now among its own kind.

Ten scientists to talk about during Black History Month

Dr. Shirley Ann Jackson

One of my passions in life is the dissemination of the history of science to the general public. Because of this, I am appalled by how educators typically underplay American American scientists, explorers, and inventors during Black History Month. Instead of the many great men and women who have helped revolutionize the world and our understanding of it, educators tend to focus on athletes and artists.  Don't get me wrong. I think Jackie Robinson was an exceptional baseball player and a key figure in the fight against segregation and Louis Armstrong was a musical genius of the highest caliber. Children, however, need to be aware that their cultural heritage is much richer than sports and music.. 

If you are an educator and you are not an expert on the history of science, do not worry. I have compiled a list for you of 10 African American scientists, inventors, and explorers that you can easily add to your curriculum. The reason why I chose just 10 is because (as I have found out through trial and error) young people generally do not have a large enough attention span to handle any more information than this. I also want to issue a challenge to you: please do not just teach about the contributions of American Americans during the month of February. Black history is American History and needs to be taught and celebrated as part of your normal curriculum.  

1. Dr. Shirley Ann Jackson (b. 1946) is a nuclear physicist and the 18th president of Rensselaer Polytechnic Institute. She attained her doctorate from MIT (where she was the first black woman to do so) and has served on many advisory boards including President Clinton's Nuclear Regulatory Commission and President Obama's Council of Advisors on Science and Technology. Her research interests focus on fundamental particles, especially neutrinos.
2. Dr. Daniel Hale Williams (1858-1931) was a surgeon and cardiologist. He was the second person to repair the torn pericardium of a knife wound and the first American to perform a successful open-heart surgery. He also founded Providential Hospital (which was the first desegregated hospital in the United States) and was the first black charter member of the American College of Surgeons.
3. Mr. Matthew Henson (1866-1955) was a famous explorer and associate of Robert Peary. While he was an exceptional seaman, Mr. Henson is mostly noted for his expedition to the North Pole in 1909. On this voyage, he became the first person to reach the geographic North Pole. Later in his life, Mr. Henson was awarded a silver medal and recognized by presidents Truman and Eisenhower for his incredible achievement.     
4. Dr. Percy Lavon Julian (1899-1975) was a chemist who focused on the chemical synthesis of medicine from plants. He is most notable for his synthesizing of physostigmine and his pioneering work in the industrial large scale synthesizing of hormones, steroids, testosterone, and progesterone. His work would laid the foundation for the production of cortisone and birth control pills. 
5. Dr. J. Ernest Wilkins Jr.(1923-2011) was a nuclear physicist and mathematician. He is remembered in part because he started the University of Chicago at the ago of 13 and achieved a doctorate by the age of 19. After this, he worked on the Manhattan Project under the tutelage of Enrico Fermi. Throughout his life, he made many contributions to calculus, engineering and nuclear physics, he served as president of the American Nuclear Society, and was the second African American to be elected to the National Academy of Engineering. .
6. Dr. Mae Jemison (b. 1956) is a physician and retired astronaut. Despite her excellent record as as a medical doctor, Dr. Jemison's greatest accomplishment is being the first black woman to travel into space. She accomplished this feat on September 12, 1992 when she went into orbit abroad the Space Shuttle Endeavour. Although she is now retired from NASA, she logged 190 1/2 hours in space. She has also appeared on Star Trek: Next Generation. 
7. Dr. Patricia Bath (b. 1942) is an inventor and ophthalmologist. She was the first woman to serve on the staff of the Jules Stein Eye Institute or to head a post-graduate program in ophthalmology at the UCLA Medical Center. She was also the first black person to serve as a resident in ophthalmology at New York University. Dr. Bath also holds several medical patents, including one for a Laserphaco Probe (which is used to treat cataracts). She also founded the American Institute for the Prevention of Blindness.
8. Dr. Samuel Kountz (1930-1981) was a transplant surgeon. He was a pioneer in the field of kidney transplants and performed the first successful kidney transplant between two people who were not identical twins. He was also part of a team that developed a prototype for the Belzer kidney perfusion machine. At the time of his death, Dr. Kountz had performed 500 kidney transplants (which was, at the time, more than anyone in the world).  
9. Dr. Ida Stephens Owens  (b. 1940) is a biochemist, geneticist, and physiologist. A member of the National Institutes of Health, Dr. Owens researches the genetics of detoxification enzymes. Her research has helped scientists gain a much better understanding of  how the human body defends itself against poison. She is currently a member of multiple research bodies, including the Section of Genetic Disorders of Drug Metabolism and the National Institute of Child Health and Human Development.
10. Dr. David Blackwell (1919-2010) was a statistician, the first African American inducted into the National Academy of the Sciences, and the first black tenured professor at UC Berkeley. He is most known in mathematics for proposing the Blackwell channel and co-discovering the Rao-Blackwell theorem. Dr. Blackwell also made many contributions to game theory and authored one of the first textbooks on Bayesian statistics in the late 1960's.

Young minds polluted at a museum

This clip is from a Nightline special that addressed faith in America. If you have never seen it before, I want you to pay attention to the way that the Young Earth Creationists use of the concept of worldview to argue that evolution stems from philosophical assumptions. It is also worth mentioning that the museum's curator, Kirk Johnson, now has a very high profile job at the American Museum for Natural History.