Home » Posts tagged 'Teaching' (Page 10)
Tag Archives: Teaching
How can students gain self-esteem? Myths and facts
What is self-esteem? The degree to which the qualities and characteristics contained in one’s self-concept are perceived to be positive. It reflects a person’s physical self-image, view of his or her accomplishments and capabilities, and values and perceived success in living up to them, as well as the ways in which others view and respond to that person.
The more positive the cumulative perception of these qualities and characteristics, the higher one’s self-esteem. A reasonably high degree of self-esteem is considered an important ingredient of mental health, whereas low self-esteem and feelings of worthlessness are common
– American Psychological Association Dictionary of Pyschology
Created by FireflySixtySeven, CC BY-SA 4.0, Wikimedia
Should families and schools raise a student’s self-esteem, and if so, how? Here it becomes essential to differential myths from facts
Exploding the Self-Esteem myth
“Boosting people’s sense of self-worth has become a national preoccupation. Yet surprisingly, research shows that such efforts are of little value in fostering academic progress or preventing undesirable behavior
A 1999 study by Donelson R. Forsyth and Natalie A. Kerr of Virginia Commonwealth University suggests that attempts to boost self-esteem among struggling students may backfire.
College students getting grades of D or F in a psychology course were divided into two groups, arranged initially to have the same grade-point average. Each week students in the first group received an e-mail message designed to boost their self-esteem [see example at left]. Those in the second group received a message intended to instill a sense of personal responsibility for their academic performance (right).
By the end of the course, the average grade in the first group dropped below 50 percent—a failing grade. The average for students in the second group was 62 percent—a D minus, which is poor but still passing. “
Quote and table from Exploding the Self-Esteem Myth, Roy F. Baumeister et al.
By Roy F. Baumeister, Jennifer D. Campbell, Joachim I. Krueger and Kathleen D. Vohs, Scientific American, January, 2005, Vol 292, Issue 1
Self Esteem Doesn’t Make Better People Of Us
Self-esteem is bad for you (and even worse for your kids).
Michael J. Formica, Psychology Today, May 17, 2008
The American philosopher and psychologist William James first coined the term self-esteem in his seminal work The Principles of Psychology. He suggested that self-esteem can be objectively measured through a simple ratio of goals and aims to attainment. What he was talking about is what we refer to today as an evidence-based measure.
Since it was first introduced in 1890, the notion of self-esteem has morphed into something entirely different than was originally intended. Our modern interpretation is no longer an objective and measurable equation of “do good/feel good”. It has, in fact, come to mean something quite the opposite. We have lost sight of the “do good” piece and now, apparently much to our detriment, focus solely on the “feel-good” piece.
…. An exhaustive 2005 study published in Scientific American by psychologist, Florida State University professor and PT Interactions Blogger Roy Baumeister demonstrated that less than 200 of the more than 15,000 articles published on self-esteem between 1970 and 2000 met any sort of standard for academic or scientific rigor.
Baumeister’s Scientific American article, in addition to both challenging and largely discrediting the existing research on self-esteem, also demonstrated that artificially boosting self-esteem actually lowers performance.
Further, high self-esteem was found to have no positive correlation with a person’s ability to have successful relationships. Quite to the contrary, Baumeister writes, “Those who think highly of themselves are more likely than others to respond to problems by severing relations and seeking other partners.”
Baumeister and his team also found that, again contrary to previous belief, low self-esteem does not cause teens to engage in earlier sexual activity. In fact, those with high self-esteem were found to be less inhibited and more likely to be sexually active.
In another contrary finding, there was no correlation of aggression and violence with low self-esteem, also a commonly held belief. In point of fact, perpetrators of aggressive and violent acts typically hold a more favorable, and possibly even inflated, view of themselves.
Self-Esteem Is Overrated
Sandra Upson, Scientific American, September 1, 2013
Scientificamerican.com Self-esteem-overrated
Self-Esteem Can Be an Ego Trap.
If your self-worth depends on success, you may be in for a fall. To feel good about yourself, think less about you and more about others
By Jennifer Crocker, Jessica J. Carnevale, Scientific American 2013
Scientific American – Self-esteem-overrated
Narcissism and Self-Esteem Are Very Different
They have very different developmental pathways and outcomes. By Scott Barry Kaufman, October 29, 2017, Scientific American
Scientific American – Narcissism-and-self-esteem-are-very-different
Why Do People Mistake Narcissism for High Self-Esteem?
Why people form such positive first impressions of narcissists. By Scott Barry Kaufman, December 3, 2018, Scientific American
Scientific American – Why-do-people-mistake-narcissism-for-high-self-esteem
How the Self-Esteem Craze Took Over America And why the hype was irresistible
By Jesse Singal, 5/2017, The Cut
Self-esteem-grit-do-they-really-help
Does High Self-Esteem Cause Better Performance, Interpersonal Success, Happiness, or Healthier Lifestyles?
By Baumeister RF, Campbell JD, Krueger JI, Vohs KD.
Psychological science in the public interest : a journal of the American Psychological Society, 2003 May;4(1):1-44.
https://www.ncbi.nlm.nih.gov/pubmed/26151640
Journals.sagepub.com – Copy of article
Related topics
Maslow’s hierarchy of needs – claims and reality
Building a RC car: Elective
In this elective our students will build a remote control car from a lego-like construction set, addressing the learning standards listed below.
Goals: Fun, and developing fine motor skills; Reading and precisely following. step-by-step instructions. Discerning exact sequence of cause-and-effect for simple machines.
Here one of our students is engaged in the build.
Learning Standards
Massachusetts Science and Technology/Engineering Curriculum Framework
Using simple machines in engineering
HS-ETS4-5(MA). Explain how a machine converts energy, through mechanical means, to do work. Collect and analyze data to determine the efficiency of simple and complex machines.
7.MS-ETS3-4(MA). Show how the components of a structural system work together to serve a structural function. Provide examples of physical structures and relate their design to their intended use.
Appendix VIII Value of Crosscutting Concepts and Nature of Science in Curricula
Cause and Effect: Mechanism and Explanation. Events have causes, sometimes simple, sometimes multifaceted. A major activity of science and engineering is investigating and explaining causal relationships and the mechanisms by which they are mediated. Such mechanisms can then be tested across given contexts and used to predict and explain events in new contexts or design solutions.
College Board Standards for College Success: Science
Standard PS.1 Interactions, Forces and Motion
Changes in the natural and designed world are caused by interactions. Interactions of an object with other objects can be described by forces that can cause a change in motion of one or both interacting objects. Students understand that the term “interaction” is used to describe causality in science: Two objects interact when they act on or influence each other to cause some effect.
Massachusetts Digital Literacy and Computer Science (DLCS) Curriculum Framework
6-8.CS.a.4 Identify and describe the use of sensors, actuators, and control systems in an embodied system (e.g., a robot, an e-textile, installation art, smart room).
Should schools have Blizzard Bags during snow days?
The idea behind “blizzard bags” and similar programs is to provide an alternative to making up school days missed due to weather disruptions or other unplanned school closures. The MTA Board has some serious concerns about blizzard bags.
Image from wwjnewsradio.radio.com
Share your thoughts on ‘blizzard bags’, MTA
In February, we asked MTA members for their thoughts on what the Department of Elementary and Secondary Education refers to as “alternative structured learning day programs” — otherwise known as “blizzard bags.” Your input will help guide our activism on this matter.
We asked, you answered: Your ‘blizzard bag’ responses. MTA
The “Blizzard Bags” program that allowed Massachusetts students to do class work at home during a winter storm and not have to make up the day in the summer comes to an end with this academic year.
The Massachusetts Department of Elementary and Secondary Education announced in June that it was discontinuing the Alternative Structured Learning Day Program, commonly known as “Blizzard Bags,” in fall 2020. It based its decision on a review of the “development and implementation of these programs.”
Some parents argued that “Blizzard Bags” could not take the place of a full day of school with face-to-face instruction or adequately address the needs of students on Individualized Education Programs.
Also, the Massachusetts Teachers Association voiced “serious concerns” about “Blizzard Bags” as a means of making up for a lost day of classroom instruction.
In the fall of 2018, the state Department of Elementary and Secondary Education established a working group to review the policy. Representatives from the Massachusetts Teachers Association participated, along with representatives of administrators from 10 Massachusetts school districts.
“The decision to discontinue the use of Alternative Structured Learning Day Programs is based upon a variety of factors, including concerns about equitable access for all students,” Jeffrey C. Riley, commissioner of Elementary and Secondary Education, stated on the state DESE website on June 27. “In addition to making every attempt to reschedule school days lost due to inclement weather, leaders should consider holding the first day of school prior to Labor Day. Other possibilities include scheduling a one-week vacation in March instead of week-long vacations in February and April.”
‘Blizzard Bags’ to be dropped by Massachusetts schools after this winter. MassLive.com
But here’s a question that almost no one seemed to even ask: Do snow days actually affect a student’s learning? This study claims that they don’t:
“Snow days don’t subtract from learning”
School administrators may want to be even more aggressive in calling for weather-related closures. A new study conducted by Harvard Kennedy School Assistant Professor Joshua Goodman finds that snow days do not impact student learning. In fact, he finds, keeping schools open during a storm is more detrimental to learning than a closure.
The findings are “consistent with a model in which the central challenge of teaching is coordination of students,” Goodman writes. “With slack time in the schedule, the time lost to closure can be regained. Student absences, however, force teachers to expend time getting students on the same page as their classmates.”
Goodman, a former school teacher, began his study at the behest of the Massachusetts Department of Education, which wanted to know more about the impact of snow days on student achievement. He examined reams of data in grades three through 10 from 2003 to 2010. One conclusion — that snow days are less detrimental to student performance than other absences — can be explained by the fact that school districts typically plan for weather-related disruptions and tack on extra days in the schedule to compensate. They do not, however, typically schedule make-up days for other student absences.
The lesson for administrators might be considered somewhat counterintuitive. “They need to consider the downside when deciding not to declare a snow day during a storm — the fact that many kids will miss school regardless, either because of transportation issues or parental discretion. And because those absences typically aren’t made up in the school calendar, those kids can fall behind.”
Goodman, an assistant professor of public policy, teaches empirical methods and the economics of education. His research interests include labor and public economics, with a particular focus on education policy.
Snow days don’t subtract from learning. The Harvard Gazette
Flaking Out: Snowfall, Disruptions of Instructional Time, and Student Achievement, by Joshua Goodman, Harvard Kennedy School of Government, April 30, 2012
Flaking Out: Snowfall, Disruptions of Instructional Time, and Student Achievement
Why learn math?
Why learn math? When are going to use this in real life?
When students ask “when will we ever need this in real life?” they often aren’t actually being curious about their future. They are actually just unhappy with being assigned work in the present. But some students truly do want to learn the answers to this question – and teachers, one would hope – should know answers as well. And there are several answers to this question, not just one.
I. First we should recognize that this is an unfair question. Douglas Corey, at Brigham Young University, writes:
In truth, the when-will-I-use-this question is unfair for the teacher. She doesn’t know when you will (or even might) use it (except on the exam and in the next course in the sequence). She might explain how other people have used it, but, as we saw above, that response is not convincing. The difficulty in answering this question lies with an implicit assumption hidden beneath the question. The student has an idea of the kinds of situations that she will encounter in her life, and when the response from the teacher doesn’t apply to any of these situations, the mathematics seems useless. But it is fraudulent to assume that we know at a moment of reflection the kinds of situations in which we might use something. Why? Because we typically don’t know what we don’t know.
– When Will I Ever Use This? An Essay for Students Who Have Ever Asked This Question in Math Class
II. Does a football team go onto the field and lift weights? Of course the team doesn’t do that. However if they didn’t practice lifting weights then they certainly wouldn’t have a chance to win.
III. We’re actually not learning hard math that mathematicians study in university. For every subject that you think you are studying – algebra, trigonometry, calculus, etc. – you’re really just learning the introduction to these subjects! Yes, even after a year in high school calculus all you have done is scratch the surface of that field of math.
So why learn any of these math topics at all in grades K-12? Because children don’t know what they are going to be 10 or 20 years from now. So consider: If we don’t teach students how to be fluent and literate in English, then how can they read and learn anything? How can they communicate using the written word? They literally would be unable to even consider a career, right?
Now realize that the same is true for math. If we don’t teach students how to be fluent and literate in mathematics and logical thinking, then how could they ever even have a chance to consider a career in medicine, engineering, coding, chemistry, artificial intelligence, astronomy, physics, or math? No one ever would even be able to consider such a career.
IV. Here I’m excerpting some thoughts from Al Sweigart.
A math teacher is giving a lesson on logarithms or the quadratic equation or whatever and is asked by a student, “When will I ever need to know this?”
“Most likely never,” replied the teacher without hesitation. “Most jobs and even a lot of professions won’t require you to know any math beyond basic arithmetic or a little algebra.”
“But,” the teacher continued, “let me ask you this. Why do people go to the gym and lift weights? Do they all plan on becoming Olympic weight lifters, or professional body builders? Do they think they’ll one day find an old lady trapped under a 200 pound bar bell and say, ‘This is what I’ve been training for.’”
“No, they lift weights because it makes them stronger. Learning math is important because because it makes you smarter. It forces your brain to think in a way that normally it wouldn’t think: a way that requires precision, discipline, and abstract thought. It’s more than rote memorization, or making beautiful things, or figuring out someone’s expectations and how to appease them.”
“Doing your math homework is practice for the kind of disciplined thinking where there are objective right and wrong answers. And math is ubiquitous: it comes up in a lot of other subjects and is universal across cultures. And all this is practice for thinking in a new way. And being able to think in new ways, more than anything, is what will prepare you for an unpredictable, even dangerous, future.”
IV. We learn mathematics without realizing its ramifications and applications
This attitude comes partly from ignorance and partly from our faulty education system. We learn mathematics without realizing its ramifications and applications. You have been led to believe that it is useless but it is not. Look around the world in which you live. Almost everything that you experience and enjoy is possible because of mathematics.
You drive a car. A car company uses CAD software which lets it design and model components with absurd ease. Do you know how a CAD software works? It uses rigorous mathematics from geometry to matrices.
That’s one part of it. The calculation part. To display a model on your computer screen is yet another story. Processes are set, algorithms are developed and executed. But merely developing an algorithm is not sufficient. You have to optimize it. To develop and optimize an algorithm you need mathematics. Somebody has to develop the optimization algorithm. Know that the optimization algorithm is an algorithm to optimize a different algorithm. To develop such feat you would probably need to master functions, graphs and calculus. To perform stress analysis on such a component you would need yet another algorithms. To develop them you would probably need to study finite element analysis and matrices. This is true for any industry and not just for car industry.
Consider a security firm. It need to be able to identify a person’s face. They need a face recognition algorithm. Now some geeks have developed many such algorithms. Some of them are simple and less accurate while some are highly accurate but difficult to employ.
Development of each such algorithm requires extensive knowledge of matrices, probabilities, and other 100 things but do you know what is beautiful? The security firm may audit itself and using yet another mathematical process, assess exactly what type of algorithm it would need. Mathematics. Again. This is true for any forensic analysis. Fingerprint matching, face matching, pattern recognition and what not. Many private and public security firms, law enforcement agencies and spy agencies are using and developing such specialized tools thanks to mathematics.
Let’s come to gaming. You will be thrilled to know that while playing combat games, you are actually fighting with an algorithm which can ‘learn’ you. Genetic algorithm, neural networks and such things. Google it. Imagine yourself at a scene in a game. You can’t see what’s behind you in a scene, but as you look at it, the scene develops. There are special compression algorithms who use the information of the scene in compressed format when nobody is looking at it. I guess I don’t have to repeat now but still, I will. Mathematics.
Investment funds, hedge funds and other financial institutions predict the market and make decisions using mathematical software. Again, it require, number crunching, statistics, pattern recognition (which itself requires a lot of mathematics), optimization, functions and graphs and calculus (for effective predictions). Insurance companies need to use probabilistic models of customers to come up with new policies. They invest money in stock market. Now again read this paragraph just put insurance companies in place of investment funds.
Kedar Marathe, Tata Technologies, answering on Quora.
_____________________________________
V. Kalid Azad, of BetterExplained, writes in How to Develop a Mindset for Math
Math uses made-up rules to create models and relationships. When learning, I ask:
-
What relationship does this model represent?
-
What real-world items share this relationship?
-
Does that relationship make sense to me?
They’re simple questions, but they help me understand new topics. If you liked my math posts, this article covers my approach to this oft-maligned subject. Many people have left insightful comments about their struggles with math and resources that helped them.
Math Education
Textbooks rarely focus on understanding; it’s mostly solving problems with “plug and chug” formulas. It saddens me that beautiful ideas get such a rote treatment:
-
The Pythagorean Theorem is not just about triangles. It is about the relationship between similar shapes, the distance between any set of numbers, and much more.
-
e is not just a number. It is about the fundamental relationships between all growth rates.
-
The natural log is not just an inverse function. It is about the amount of time things need to grow.
Elegant, “a ha!” insights should be our focus, but we leave that for students to randomly stumble upon themselves. I hit an “a ha” moment after a hellish cram session in college; since then, I’ve wanted to find and share those epiphanies to spare others the same pain.
But it works both ways — I want you to share insights with me, too. There’s more understanding, less pain, and everyone wins.
Math Evolves Over Time
I consider math as a way of thinking, and it’s important to see how that thinking developed rather than only showing the result. Let’s try an example.
Imagine you’re a caveman doing math. One of the first problems will be how to count things. Several systems have developed over time:
fro Kalid Azad, BetterExplained
No system is right, and each has advantages:
-
Unary system: Draw lines in the sand — as simple as it gets. Great for keeping score in games; you can add to a number without erasing and rewriting.
-
Roman Numerals: More advanced unary, with shortcuts for large numbers.
-
Decimals: Huge realization that numbers can use a “positional” system with place and zero.
-
Binary: Simplest positional system (two digits, on vs off) so it’s great for mechanical devices.
-
Scientific Notation: Extremely compact, can easily gauge a number’s size and precision (1E3 vs 1.000E3).
Think we’re done? No way. In 1000 years we’ll have a system that makes decimal numbers look as quaint as Roman Numerals (“By George, how did they manage with such clumsy tools?”).
Negative Numbers Aren’t That Real
Let’s think about numbers a bit more. The example above shows our number system is one of many ways to solve the “counting” problem.
The Romans would consider zero and fractions strange, but it doesn’t mean “nothingness” and “part to whole” aren’t useful concepts. But see how each system incorporated new ideas.
Fractions (1/3), decimals (.234), and complex numbers (3 + 4i) are ways to express new relationships. They may not make sense right now, just like zero didn’t “make sense” to the Romans. We need new real-world relationships (like debt) for them to click.
Even then, negative numbers may not exist in the way we think, as you convince me here:
You: Negative numbers are a great idea, but don’t inherently exist. It’s a label we apply to a concept.
Me: Sure they do.
You: Ok, show me -3 cows.
Me: Well, um… assume you’re a farmer, and you lost 3 cows.
You: Ok, you have zero cows.
Me: No, I mean, you gave 3 cows to a friend.
You: Ok, he has 3 cows and you have zero.
Me: No, I mean, he’s going to give them back someday. He owes you.
You: Ah. So the actual number I have (-3 or 0) depends on whether I think he’ll pay me back. I didn’t realize my opinion changed how counting worked. In my world, I had zero the whole time.
Me: Sigh. It’s not like that. When he gives you the cows back, you go from -3 to 3.
You: Ok, so he returns 3 cows and we jump 6, from -3 to 3? Any other new arithmetic I should be aware of? What does sqrt(-17) cows look like?
Me: Get out.
Negative numbers can express a relationship:
-
Positive numbers represent a surplus of cows
-
Zero represents no cows
-
Negative numbers represent a deficit of cows that are assumed to be paid back
But the negative number “isn’t really there” — there’s only the relationship they represent (a surplus/deficit of cows). We’ve created a “negative number” model to help with bookkeeping, even though you can’t hold -3 cows in your hand. (I purposefully used a different interpretation of what “negative” means: it’s a different counting system, just like Roman numerals and decimals are different counting systems.)
By the way, negative numbers weren’t accepted by many people, including Western mathematicians, until the 1700s. The idea of a negative was considered “absurd”. Negative numbers do seem strange unless you can see how they represent complex real-world relationships, like debt.
Why All The Philosophy?
I realized that my **mindset is key to learning. **It helped me arrive at deep insights, specifically:
-
Factual knowledge is not understanding. Knowing “hammers drive nails” is not the same as the insight that any hard object (a rock, a wrench) can drive a nail.
-
Keep an open mind. Develop your intuition by allowing yourself to be a beginner again.
A university professor went to visit a famous Zen master. While the master quietly served tea, the professor talked about Zen. The master poured the visitor’s cup to the brim, and then kept pouring. The professor watched the overflowing cup until he could no longer restrain himself. “It’s overfull! No more will go in!” the professor blurted. “You are like this cup,” the master replied, “How can I show you Zen unless you first empty your cup.”
-
Be creative. Look for strange relationships. Use diagrams. Use humor. Use analogies. Use mnemonics. Use anything that makes the ideas more vivid. Analogies aren’t perfect but help when struggling with the general idea.
-
Realize you can learn. We expect kids to learn algebra, trigonometry and calculus that would astound the ancient Greeks. And we should: we’re capable of learning so much, if explained correctly. Don’t stop until it makes sense, or that mathematical gap will haunt you. Mental toughness is critical — we often give up too easily.
So What’s The Point?
I want to share what I’ve discovered, hoping it helps you learn math:
-
Math creates models that have certain relationships
-
We try to find real-world phenomena that have the same relationship
-
Our models are always improving. A new model may come along that better explains that relationship (roman numerals to decimal system).
Sure, some models appear to have no use: “What good are imaginary numbers?”, many students ask. It’s a valid question, with an intuitive answer.
The use of imaginary numbers is limited by our imagination and understanding — just like negative numbers are “useless” unless you have the idea of debt, imaginary numbers can be confusing because we don’t truly understand the relationship they represent.
Math provides models; understand their relationships and apply them to real-world objects.
Developing intuition makes learning fun — even accounting isn’t bad when you understand the problems it solves. I want to cover complex numbers, calculus and other elusive topics by focusing on relationships, not proofs and mechanics.
But this is my experience — how do you learn best?
This section by Kalid Azad was made under a Creative Commons Attribution-NonCommercial-ShareAlike license.
.
Teaching science with augmented reality
Using virtual reality in the classroom
We learn through lectures and reading. We especially learn through illustrations, photographs, diagrams, and animations. But a limitation is that so many of these images are flat, two-dimensional. Not surprisingly, many folks have trouble visualizing what a system is really like, if they only have two dimensional pictures.
An obvious practical solution is to make a lesson hands-on: Students can take a field trip to see gears and machines in a power plant; see ancient ruins on site; travel to a valley and fly over a vast ecosystem to see different parts of the environment. But there’s only so much that a school can do in practice: we can’t purchase every manipulative and lab, or travel to see every place that we talk about.
Yet with today’s technology we can actually model machines, cells, valleys and volcanoes, ecosystems, distance cities, and archaeological sites, in three dimensions – and then bring all of this into the classroom. We bring these models in to a virtual space that students can explore.
And that’s what we are already doing in our classrooms! First, let’s learn a few terms: XR, AR, and VR.
XR- Extended Reality
the emerging umbrella term for all immersive computer virtual experience technologies. These technologies AR, VR, and MR.
Augmented Reality (AR)
When virtual information and objects are overlaid on the real world. This experience enhances the real world with digital details such as images, text, and animation. This means users are not isolated from the real world and can still interact and see what’s going on in front of them.
CRISPR enzyme floating in three dimensions.
Photo by RK (c) 2019
Virtual Reality (VR)
Users are fully immersed in a simulated digital environment. Individuals must put on a VR headset or head-mounted display to get a 360 -degree view of an artificial world. This fools their brain into believing they are walking on the moon, swimming under the ocean or stepped into whatever new world the VR developers created.
A team of researchers at ESA’s mission control centre in Darmstadt, Germany, are investigating new concepts for controlling rovers on a planet and satellites in orbit. Image from the ESA, esa.int/ESA_Multimedia/Images/2017/07/Reality_check
Mixed reality (MR), aka Hybrid Reality
Digital and real-world objects co-exist and can interact with one another in real-time. This experience requires an MR headset… Microsoft’s HoloLens is a great example that, e.g., allows you to place digital objects into the room you are standing in and give you the ability to spin it around or interact with the digital object in any way possible.
Image from Microsoft
Excerpts of these definitions from Bernard Marr, What Is Extended Reality Technology? A Simple Explanation For Anyone, Forbes, 8/12/2019
Augmented reality in Ecology & Environmental Science
When students actively participate in augmented reality learning, the class is effectively a lab, as opposed to being a lecture. Here we are studying ecosystems with an app from the World Wildlife Foundation, WWF Rivers.
Photo by RK (c) 2019
This student has their head in the clouds 😉
Photo by RK (c) 2019
Here we are using the Google Expeditions app, on a Pixel 3A smartphone. The plug-in is “Earth Geology” by Vida systems. For more details see Google Expeditions – Education in VR.
AR in Earth Science
As we walk around the room, we see the Earth and all of it’s layers in a realistic 3D view. Here we stood above the arctic circle, and took screenshots as we moved down latitude, until we were above the antarctic.
Photo by RK (c) 2019
Photo by RK (c) 2019
AR in Physics & Engineering
A simple machine is a mechanical device that changes the direction or magnitude of a force. They are the simplest mechanisms that use mechanical advantage to multiply force.
Here we are examining gears, including bicycle gears.
Photo by RDK (c) 2019
Related Special Education topics
If you can’t visually imagine things, how can you learn?
If someone can’t visually imagine things, how can you learn? We know some people can’t conjure up mental images. But we’re only beginning to understand the impact this “aphantasia” might have on their education.
A discussion of an inability to form mental images , congenital aphantasia. This is believed to affect 2% of the population.
by Mo Costandi, Jun 2016, The Guardian, UK
Learning Standards
What kind of learning standards will students address when using augmented reality science lessons?
NGSS Cross-Cutting Concepts
6. Structure and Function – The way an object is shaped or structured determines many of its properties and functions: Complex and microscopic structures and systems can be visualized, modeled, and used to describe how their function depends on the shapes, composition, and relationships among its parts; therefore, complex natural and designed structures/systems can be analyzed to determine how they function
Massachusetts Digital Literacy and Computer Science (DLCS) Curriculum Framework
Modeling and Simulation [6-8.CT.e] – 3. Select and use computer simulations, individually and collaboratively, to gather, view, analyze, and report results for content-related problems (e.g., migration, trade, cellular function).
Digital Tools [9-12.DTC.a] – 2. Select digital tools or resources based on their efficiency and effectiveness to use for a project or assignment and justify the selection.
American Association of School Librarians: Standards Framework for Learners
1. Inquire: Build new knowledge by inquiring, thinking critically, identifying problems, and developing strategies for solving problems
Advanced Placement Computer Science Principles
AP-CSP Curriculum Guides
LO 3.1.3 Explain the insight and knowledge gained from digitally processed data by using appropriate visualizations, notations, and precise language.
EK 3.1.3A Visualization tools and software can communicate information about data.
EK 3.1.3E Interactivity with data is an aspect of communicating.
NGSS leaves out critical guidance on importance of teaching about vectors
As we all know the NGSS are more about skills than content. Confusingly, though, they ended up also listing core content topics as well – yet they left out kinematics and vectors, the basic tools needed for physics in the first place.
The NGSS also dropped the ball by often ignoring the relationship of math to physics. They should have noted which math skills are needed to master each particular area.
Hypothetically, they could have had offered options: For each subject, note the math skills that would be needed to do problem solving in this area, for
* a standard (“college prep”) level high school class
* a lower level high school class, perhaps along the lines of what we call “Conceptual Physics” (still has math, but less.)
* the highest level of high school class, the AP Physics level. And the AP study guides already offer what kinds of math one needs to do problem solving in each area.
Yes, the NGSS does have a wonderful introduction to this idea, (quoted below) – but when we look at the actual NGSS standards they don’t mention these skills.
In some school districts this has caused confusion, and even led to some administrators demanding that physics be taught without these essential techniques (i.e. kinematic equations, conceptual understanding of 2D motion, kinematic analysis of 2D motion, vectors, etc.)
To help back up teachers in the field I put together these standards for vectors, from both science and mathematics standards.
– Robert Kaiser
Learning Standards
Massachusetts Science Curriculum Framework (pre 2016 standards)
1. Motion and Forces: Central Concept: Newton’s laws of motion and gravitation describe and predict the motion of most objects.
1.1 Compare and contrast vector quantities (e.g., displacement, velocity, acceleration force, linear momentum) and scalar quantities (e.g., distance, speed, energy, mass, work).
NGSS
Science and Engineering Practices: Using Mathematics and Computational Thinking
Mathematical and computational thinking in 9–12 builds on K–8 experiences and progresses to using algebraic thinking and analysis, a range of linear and nonlinear functions including trigonometric functions, exponentials and logarithms, and computational tools for statistical analysis to analyze, represent, and model data. Simple computational simulations are created and used based on mathematical models of basic assumptions.
- Apply techniques of algebra and functions to represent and solve scientific and engineering problems.
Although there are differences in how mathematics and computational thinking are applied in science and in engineering, mathematics often brings these two fields together by enabling engineers to apply the mathematical form of scientific theories and by enabling scientists to use powerful information technologies designed by engineers. Both kinds of professionals can thereby accomplish investigations and analyses and build complex models, which might otherwise be out of the question. (NRC Framework, 2012, p. 65)
Students are expected to use mathematics to represent physical variables and their relationships, and to make quantitative predictions. Other applications of mathematics in science and engineering include logic, geometry, and at the highest levels, calculus…. Mathematics is a tool that is key to understanding science. As such, classroom instruction must include critical skills of mathematics. The NGSS displays many of those skills through the performance expectations, but classroom instruction should enhance all of science through the use of quality mathematical and computational thinking.
Common Core Standards for Mathematics (CCSM)
High School: Number and Quantity » Vector & Matrix Quantities. Represent and model with vector quantities.
Represent and model with vector quantities.
CCSS.MATH.CONTENT.HSN.VM.A.1
(+) Recognize vector quantities as having both magnitude and direction. Represent vector quantities by directed line segments, and use appropriate symbols for vectors and their magnitudes (e.g., v, |v|, ||v||, v).
(+) Recognize vector quantities as having both magnitude and direction. Represent vector quantities by directed line segments, and use appropriate symbols for vectors and their magnitudes (e.g., v, |v|, ||v||, v).
CCSS.MATH.CONTENT.HSN.VM.A.2
(+) Find the components of a vector by subtracting the coordinates of an initial point from the coordinates of a terminal point.
(+) Find the components of a vector by subtracting the coordinates of an initial point from the coordinates of a terminal point.
CCSS.MATH.CONTENT.HSN.VM.A.3
(+) Solve problems involving velocity and other quantities that can be represented by vectors.
(+) Solve problems involving velocity and other quantities that can be represented by vectors.
Perform operations on vectors.
CCSS.MATH.CONTENT.HSN.VM.B.4
(+) Add and subtract vectors.
(+) Add and subtract vectors.
CCSS.MATH.CONTENT.HSN.VM.B.4.A
Add vectors end-to-end, component-wise, and by the parallelogram rule. Understand that the magnitude of a sum of two vectors is typically not the sum of the magnitudes.
Add vectors end-to-end, component-wise, and by the parallelogram rule. Understand that the magnitude of a sum of two vectors is typically not the sum of the magnitudes.
CCSS.MATH.CONTENT.HSN.VM.B.4.B
Given two vectors in magnitude and direction form, determine the magnitude and direction of their sum.
Given two vectors in magnitude and direction form, determine the magnitude and direction of their sum.
CCSS.MATH.CONTENT.HSN.VM.B.4.C
Understand vector subtraction v – w as v + (-w), where –w is the additive inverse of w, with the same magnitude as w and pointing in the opposite direction. Represent vector subtraction graphically by connecting the tips in the appropriate order, and perform vector subtraction component-wise.
Understand vector subtraction v – w as v + (-w), where –w is the additive inverse of w, with the same magnitude as w and pointing in the opposite direction. Represent vector subtraction graphically by connecting the tips in the appropriate order, and perform vector subtraction component-wise.
CCSS.MATH.CONTENT.HSN.VM.B.5
(+) Multiply a vector by a scalar.
(+) Multiply a vector by a scalar.
CCSS.MATH.CONTENT.HSN.VM.B.5.A
Represent scalar multiplication graphically by scaling vectors and possibly reversing their direction; perform scalar multiplication component-wise, e.g., as c(vx, vy) = (cvx, cvy).
Represent scalar multiplication graphically by scaling vectors and possibly reversing their direction; perform scalar multiplication component-wise, e.g., as c(vx, vy) = (cvx, cvy).
CCSS.MATH.CONTENT.HSN.VM.B.5.B
Compute the magnitude of a scalar multiple cv using ||cv|| = |c|v. Compute the direction of cv knowing that when |c|v ≠ 0, the direction of cv is either along v (for c > 0) or against v (for c < 0).
Compute the magnitude of a scalar multiple cv using ||cv|| = |c|v. Compute the direction of cv knowing that when |c|v ≠ 0, the direction of cv is either along v (for c > 0) or against v (for c < 0).
American Association for the Advancement of Science
Operating with Symbols and Equations
- Become fluent in generating equivalent expressions for simple algebraic expressions and in solving linear equations and inequalities.
- Develop fluency operating on polynomials, vectors, and matrices using by-hand operations for the simple cases and using technology for more complex cases.
AAAS Benchmarks (American Association for the Advancement of Science)
9B9-12#2: Symbolic statements can be manipulated by rules of mathematical logic to produce other statements of the same relationship, which may show some interesting aspect more clearly. Symbolic statements can be combined to look for values of variables that will satisfy all of them at the same time.
9B9-12#5: When a relationship is represented in symbols, numbers can be substituted for all but one of the symbols and the possible value of the remaining symbol computed. Sometimes the relationship may be satisfied by one value, sometimes more than one, and sometimes maybe not at all.
12B9-12#2: Find answers to problems by substituting numerical values in simple algebraic formulas and judge whether the answer is reasonable by reviewing the process and checking against typical values.
12B9-12#3: Make up and write out simple algorithms for solving problems that take several steps.
#vectors #teaching #standards #kinematics #physics #kaiserscience #pedagogy #education #NGSS #Benchmarks #scalors #highschool
Tidal power
Content objective:
What are we learning? Why are we learning this?
content, procedures, skills
Vocabulary objective
Tier II: High frequency words used across content areas. Key to understanding directions, understanding relationships, and for making inferences.
Tier III: Low frequency, domain specific terms
Building on what we already know
What vocabulary & concepts were learned in earlier grades?
Make connections to prior lessons.
Ocean tides are caused by tidal forces.
What are “tides”?
Types of tidal power
Tidal barrages may be the most efficient way to capture energy from the tides.
Here, a dam utilizes the potential energy generated by the change in height between high and low tides.
In this example, the motion of the water spins a propeller.
image from technologystudent.com/images5/tidal1.gif
The spinning propeller spins an axle, which transmits the motion up to the generator.
Inside the generator, this motion is used to rotate wires inside a magnet (or vice-versa)
The wire feels the magnetic field changing;
this produces an electrical current inside the wires.
Thus we have converted the energy of moving water into electrical energy.
Tidal fences
Turbines that operate like giant turnstiles.
The spinning turnstiles spins an axle, which transmits the motion up to the generator.
Inside the generator, this motion is used to rotate wires inside a magnet (or vice-versa) as shown above.
Tidal turbines
Similar to wind turbines but these are underwater.
The mechanical energy of tidal currents is used to turn turbines.
These are connected to a generator that produces electricity
Other possible designs
Many other designs are possible, for instance:
Fluid Pumping Apparatuses Powered By Waves Or Flowing Currents
Great animations
Many types of tidal energy convertors (European Marine Energy Centre)
Advantages of tidal power
Environmentally friendly
Relatively small amount of space
Ocean currents generate relatively more energy than air currents. Why? Because ocean water is 832 times more dense than air. It therefore applies greater force on the turbines.
Disadvantages of tidal power
High construction costs
The amount of energy produced is not constant per hour, or even per week.
It requires a suitable site, where tidal streams are consistently strong.
The equipment must be capable of withstanding strong tides and storms.
It can be expensive to maintain and repair.
Related topics
Why Is There a Tidal Bulge Opposite the Moon?
NGSS Three dimensional learning
NGSS has three distinct components: 1. Disciplinary Core Ideas, 2. Cross Cutting Concepts, and 3. Science & Engineering Practices.
NGSS Three Dimensional Learning
Teaching Channel NGSS 3 dimensional teaching
KnowAtom’s blog – Explore the 3 Dimensions
A Way to Think About Three-Dimensional Learning and NGSS
From Carolina Biologica Supply Company,, by Dee Dee Whitaker
The National Research Council (NRC) went to science and engineering practitioners and gathered information on how they “do” science and engineering. That information was organized and the resulting framework is the Next Generation Science Standards.
- What scientists do is Dimension 1: Practices
- Concepts applied to all domains of science is Dimension 2: Crosscutting Concepts
- Big, important concepts for students to master is Dimension 3: Disciplinary Core Ideas
Each dimension is further refined into specific behaviors, concepts, and ideas. Below is a list of the three dimensions with an accompanying explanation and a brief rationale for each.
| Phenomenon
Naturally occurring events. Use phenomena to generate interest and elicit questions. |
||
| Scientific and Engineering Practices
Practices: behaviors that scientists engage
|
Disciplinary Core Ideas
The broad, key ideas within a scientific discipline make up the core ideas. The core ideas are distributed among 4 domains:
|
Crosscutting Concepts
Applicable to all science disciplines, crosscutting concepts link the disciplines together.
|
| Artifacts
Tangible evidence of demonstrated student learning. Artifacts need to be durable. A report, poster, project, and an audio recording of a presentation can all serve as artifacts. |
||
Resources from New York City
New Visions for public schools – High School Science
New Visions for public schools – High School Biology – Designed to NGSS
.
Science teaching methods
“Pedagogy is the study of teaching methods, including the aims of education and the ways in which such goals may be achieved. The field relies heavily on educational psychology, which encompasses scientific theories of learning, and to some extent on the philosophy of education, which considers the aims and value of education from a philosophical perspective.”
~ Encyclopædia Britannica
What type of teaching works with NGSS?
No one model of pedagogy is best for every topic or every teacher. Different teachers are enthusiastic about different approaches. Experienced science teachers change the mode of instruction to match the phenomenon which they are presenting.
Philip Bell and Andrew Shouse write
People often assume that a particular instructional model is best for engaging students in the NGSS practices. In fact, there are multiple models that can be used effectively.
NGSS and the underlying NRC Framework do not say anywhere that there is only one instructional approach for engaging students in the practices. But specific curricula, instructional resources, and PD can reinforce this view by focusing on only one model at a time. There are actually multiple instructional models that can be productively used to implement the learning goals of NGSS.
Explore the practice-focused instructional models listed in the table and select one(s) that fit your situation and personal preferences.
Selecting an instructional model that fits a particular classroom should be based on local circumstances. This can involve supporting instruction that fits a teacher’s personal history, goals, or commitments. Or it can be based on what instructional model is in use in the local curriculum. The district’s or school’s instructional strategy or a professional learning community may also shape teachers’ orientation to an instructional model.
From Are there multiple instructional models that fit with the science and engineering practices in NGSS?, STEM Teaching Tools
Image by Gerd Altmann, Pixabay, Free for commercial use
Flipped classroom
The flipped classroom intentionally shifts instruction to a learner-centered model. Students take responsibility to learn the content at home, usually through video lessons prepared by the teacher or third parties, and readings from textbooks. In-class lessons include activity learning, homework problems, using manipulatives, doing labs, presentations, project-based learning, skill development, etc.
An early example of this was called Peer Instruction by Harvard Professor Eric Mazur, in the early 1990s.
Just-in-Time Teaching
There is no hard line between approaches Just-In-Time teaching may be considered halfway between traditional teaching methods and the flipped classroom.
JiTT relies on pre-class assignments completed by students before class meetings. These assignments are usually completed online. The pre-class assignments cover the material that will be introduced in the subsequent class, and should be answered based on students’ reading or other preparation. The idea is to create incentive for students to complete the assigned reading before class. At college level, teachers make the pre-class assignment due at least 1 hour before class. This allows the faculty member to review the students’ answers before class.
Apps/interactive simulations
Science apps are sometimes called Physlets, Chemlets, etc. In the past many ran on Flash or JAVA. Today they are increasingly being written to run on any browser with HTML5 standards.
Apps help make the visual and conceptual models of expert scientists accessible to students.
Example: PhET Interactive Simulations
Classroom response systems (“clickers”)
A classroom response system (sometimes called a personal response system, student response system, or audience response system) is a set of hardware and software that facilitates teaching activities such as the following.
-
A teacher poses a multiple-choice question via an overhead or computer projector.
-
Each student submits an answer to the question using a clicker.
-
Software collects the answers and produces a bar chart showing how many students chose each of the answer choices.
-
The teacher makes “on the fly” choices in response to the bar chart.
Ranking Task Exercises
Conceptual physics exercises that challenges readers to make comparative judgments about a set of variations on a particular physical situation. Exercises encourage readers to formulate their own ideas about the behavior of a physical system, correct any misconceptions they may have, and build a better conceptual foundation of physics.
Interactive Lecture Demonstrations
See Interactive Lecture Demonstrations, Active Learning in Introductory Physics, by David Sokoloff and Ronald Thornton.
Start with a scripted activity in a traditional lecture format. Because the activity causes students to confront their prior understanding of a core concept, students are ready to learn in a follow-up lecture.
Interactive Lecture Demonstrations use three steps in which students:
Predict the outcome of the demonstration. Individually, and then with a partner, students explain to each other which of a set of possible outcomes is most likely to occur.
Experience the demonstration. Working in small groups, students conduct an experiment, take a survey, or work with data to determine whether their initial beliefs were confirmed (or not).
Reflect on the outcome. Students think about why they held their initial belief and in what ways the demonstration confirmed or contradicted this belief. After comparing these thoughts with other students, students individually prepare a written product on what was learned.
https://serc.carleton.edu/introgeo/demonstrations/index.html
GIFs as step-by-step animations
Textbooks and lectures use static diagrams. For many students it is hard to visualize the scientific process being taught. GIFs help students visualize a complex process.
GIFs add to our toolbook. For instance, one can model an electric series circuit with two resistors in many ways. We can model this circuit with math, with a circuit diagram, or with a GIF. With the GIF we can see how the battery adds potential energy to the electrons in a circuit, while the electrons lose this potential energy as they go through any circuit element with resistance.
https://www.stem.org.uk/news-and-views/opinions/using-gifs-classroom
http://blog.cdnsciencepub.com/science-communicators-get-your-gif-on/
http://blogs.nottingham.ac.uk/makingsciencepublic/2014/01/24/how-to-do-things-with-gifs/
Cooperative group problem solving
Cooperative Group Problem-solving – Students work in groups using structured problem-solving strategy. In this way they can solve complex, context-rich problems which could be difficult for them to solve individually.
Students in introductory physics courses typically begin to solve a problem by plunging into the algebraic and numerical solution — they search for and manipulate equations, plugging numbers into the equations until they find a combination that yields an answer (e.g. the plug-and-chug strategy).
They seldom use their conceptual knowledge of physics to qualitatively analyze the problem situation, nor do they systematically plan a solution before they begin numerical and algebraic manipulations of equations. When they arrive at an answer, they are usually satisfied — they rarely check to see if the answer makes sense.
To help students integrate the conceptual and procedural aspects of problem solving so they could become better problem solvers, we introduced a structured, five-step problem solving strategy.
5E Model (a modelling method)
The 5E model is a constructivist science learning method created in the late 1980s by the Biological Sciences Curriculum Study (BSCS Science Learning) team. The method usually has 5 steps –
Engage, student’s interest is captured,
Explore, student constructs knowledge through facilitated questioning and observation
Explain, students are asked to explain what they have discovered. Instructor leads discussion of topic to refine the students’ understanding.
Extend (Elaborate), students asked to apply what they have learned to different situations,
Evaluate.
Tutorials in Introductory Physics
Guided-inquiry worksheets for small groups in recitation section of intro calculus-based physics. Instructors engage groups in Socratic dialogue.
RealTime Physics
A series of introductory laboratory modules that use computer data acquisition tools to help students develop physics concepts and acquire lab skills.
Modeling Instruction
Instruction organized around active student construction of conceptual and mathematical models in an interactive learning community. Students engage with simple scenarios to build, test and apply the handful of scientific models that represent the content core of physics.
Force Concept Inventory
“The FCI is a test of conceputal understanding of Newtonian mechanics, developed from the late 1980s. It consists of 30 MCQ questions with 5 answer choices for each question and tests student understanding of conceptual understanding of velocity, acceleration and force. Many distracters in the test items embody commonsense beliefs about the nature of force and its effect on motion. ”
Developed by Hestenes, Halloun, Wells, and Swackhamer (1985.) Sample question:
Problem with relying solely on modeling methods
The major issues with relying solely on modeling methods, such as 5E, is that if we really followed this methodology for all topics then it would take many years to get a student through one year of a high school science class.
After all, it took some of the world’s smartest people 2,000 years of intellectual exploration to notice and understand the scientific phenomenon that make up just a one year high school science course.
There is no hope of having most high school students do all the steps in 5E for more than a small percent of physics, chemistry, or biology phenomenon in just one year.
When in science teacher discussion communities I haven’t found many people who advocated for year-long modeling as the sole or primary way to teach. The push for these methods seems to come from massive, for-profit, textbook publishing companies. They sell various 5E and NGSS labeled curricula. Older teachers have noticed that these companies always dump their own curricula and replace it with a new one every 15 years or so.
To be clear – I am not critiquing anyone who uses modeling teaching. I just am saying that there is not enough time for students to discover every phenomenon. We also need some traditional instruction: assigning reading and lecturing.
Different types of learners?
Daniel T. Willingham writes:
Question: What does cognitive science tell us about the existence of visual, auditory, and kinesthetic learners and the best way to teach them?
The idea that people may differ in their ability to learn new material depending on its modality—that is, whether the child hears it, sees it, or touches it—has been tested for over 100 years. And the idea that these differences might prove useful in the classroom has been around for at least 40 years.
What cognitive science has taught us is that children do differ in their abilities with different modalities, but teaching the child in his best modality doesn’t affect his educational achievement. What does matter is whether the child is taught in the content’s best modality.
See more at Do Visual, Auditory, and Kinesthetic Learners Need Visual, Auditory, and Kinesthetic Instruction?
External resources
www.physport.org Teaching Methods
How to teach AP Physics
ASU Modeling Instruction modeling.asu.edu/R&E/Research.html
SETI notes
The search for extraterrestrial intelligence (SETI) is a collective term for any scientific searches for intelligent extraterrestrial life.
It is done by monitoring radio signals for signs of transmissions from civilizations on other planets.
Topics
The history of SETI
Where could other forms of life exist in our solar system?
Where could other forms of life exist in our galaxy?
How likely is it that life would exist? The Drake Equation
What exactly is our galaxy?
How could we detect sings of intelligent life from outside of our solar system?
scanning radio waves
Why don’t any Earthly organisms detect radio waves?
so what are radio waves, and how do we detect them?
The Water hole: What radio frequencies should we listen to?
Misconceptions about listening with radio telescopes
How can we differentiate between natural or artificial (intelligent) signals?
scanning infrared for signs of Dyson spheres or other megastructures
so what is IR, and how do we detect it?
Where might we find life?
Goldilocks Zone/Circumstellar habitable zone – single star systems
Habitable zones for binary star systems
Atmosphere of brown dwarf stars
surface of neutron stars (very speculative)
Could we realistically ever travel to other star systems? physics of interstellar travel
Where would other forms of intelligent life exist?
There may be other forms of life even here in our own solar system, but almost certainly that would be only primitive, single celled organisms.
That being said, the number of worlds in our own solar system where life may exist, even right now, is larger than more people think. For a variety of reasons, scientists believe that there is a possibility of life existing on
Europa, a moon of Jupiter
https://europa.nasa.gov/why-europa/ingredients-for-life/
NASA Europa Clipper expedition
Europa: A World of Ice, With Potential for Life. NASA
NASA Europa in depth
Enceladus, a moon of Saturn
https://solarsystem.nasa.gov/missions/cassini/science/enceladus/
https://solarsystem.nasa.gov/resources/17649/ingredients-for-life-at-enceladus/
https://solarsystem.nasa.gov/moons/saturn-moons/enceladus/in-depth/
Mars
https://mars.nasa.gov/news/8863/searching-for-life-in-nasas-perseverance-mars-samples/
https://en.wikipedia.org/wiki/Life_on_Mars
https://www.nature.com/immersive/d41586-021-00321-7/index.html
https://mars.nasa.gov/science/goals/
https://www.smithsonianmag.com/science-nature/life-on-mars-78138144/
NASA Viking mission: Evidence of Life on Mars in the 1970s
Jupiter – ideas about how life could exist in its upper cloud layers.
Carl Sagan, Cosmos. Possibility of life on Jupiter. Video
Particles, environments, and possible ecologies in the Jovian atmosphere.. Carl Sagan
https://www.centauri-dreams.org/2009/02/25/edwin-salpeter-and-the-gasbags-of-jupiter/
What exactly is our solar system? See our resource the Solar system.
When we talk about SETI, we’re not looking for life in general, but we’re looking for very complex forms of life that have evolved intelligence and the ability to communicate with the electromagnetic spectrum.
Such life could exist on other planets, or large moons, around other stars in our galaxy, the Milky Way.
At this point we should take a look at what we mean by “galaxy”.
Here is a view of our galaxy as seen from Earth, New Hampshire.
This is what our galaxy would look like if we were above the galactic center, looking down at it.
There are approximately 100 billion stars in our galaxy, with perhaps one trillion planets and large moons, each of which has existed for billions of years. Many scientists believe it likely that life has evolved on many of these worlds.
For a variety of reasons, we have reason to believe that many of these worlds would in many ways be Earth-like, some of them larger than Earth. These are often called super earths.
Dimitar D. Sasselov and Diana Valencia, Planets We Could call home, Scientific American, 303, 38 – 45 (2010)
Current – and even any other potentially feasible – technology is unable to let us detect SETI signals from life on planets in other galaxies. If we were to consider other galaxies, the odds of intelligent life existing somewhere out there is considered near certain.
Observations with the Hubble Space Telescope reveal that there are about two trillion galaxies in the observable universe – each of these galaxies likely having billions of planets and large moons.
This photo shows the Sombrero galaxy, m104. The other points of light around it are not stars, but entire galaxies!
A Hubble Space Telescope image of the Sombrero galaxy, M104 (credit: NASA)
At this point we should stop and clarify precisely what we mean by the word “universe.” – The universe
What are radio waves?
Radio waves are just a part of the EM (electromagnetic) spectrum.
That sounds dandy, except, what exactly is the “electromagnetic spectrum”?
All parts of the EM spectrum – radio, visible light, etc. – are oscillating electric and magnetic fields.
For details see Light is an electromagnetic field.
How are radio waves different from other parts of the EM spectrum?
They’re made of the same thing, behaving in exactly the same way.
The only difference is that radio waves are hundreds of meters to thousands of meters long.
Other parts of the EM spectrum have longer or shorter waves.
What creates radio waves?
With a radio receiver we can hear radio waves coming from all around us. They are naturally produced, and comes from all over the Earth, and outer space.
Radio waves are naturally created by:
* Wind whipping over a surface, creating static electricity
(Here’s a more mundane example of static electricity.)
* Lightning
* atoms trapped in the magnetic fields around the Earth, and around all other planets as well.
* The Sun (it puts out all frequencies of EM radiation!)
* All stars
* Ionized interstellar gas surrounding bright, hot stars
HST (Hubbble Space Telescope) Image: Gaseous Pillars In M16-Eagle Nebula Pillars Of Creation In A Star- Forming Region
* Supernovas
* There are also more complex radio waves that are naturally generated. See Natural and man-made terrestrial electromagnetic noise
By the late 1800’s humans had learned not only how to receive radio waves, but how to generate them.
Today we artificially create radio waves for all sorts of purposes, including
-
Traditional, over-the-air, radio stations (AM and FM radio)
-
Traditional, old-fashioned, TV (television)
-
Wi-Fi
-
Bluetooth
-
Cellphone communication (cell towers and the phones)
Cornell.edu: Observational-astronomy. SETI and extraterrestrial life
Kaiserscience – All about the electromagnetic spectrum
What is a radio telescope?
The technology of how we detect radio waves.
http://abyss.uoregon.edu/~js/glossary/radio_telescope.html
Image from website of James Schombert, Dept of Physics, Univ. Oregon
How does an antenna pick up radio waves?
“If we place a conducting material on the path of such a wave, the passing wave will create an oscillating electric field inside the material; and that field will accelerate charges back and forth through the conductor.”
https://en.wikipedia.org/wiki/Antenna_(radio)
http://spiff.rit.edu/classes/ast613/lectures/radio_ii/radio_ii.html
The history of SETI
This section has been adapted from “Search for extraterrestrial intelligence.” Wikipedia, The Free Encyclopedia. 4 Mar. 2019
There have been many earlier searches for extraterrestrial intelligence within the Solar System. In 1896, Nikola Tesla suggested that an extreme version of his wireless electrical transmission system could be used to contact beings on Mars. He conducted an experiment at his Colorado Springs experimental station.
In the early 1900s, Guglielmo Marconi, Lord Kelvin and David Peck Todd also stated their belief that radio could be used to contact Martians, with Marconi stating that his stations had also picked up potential Martian signals.
On August 21–23, 1924, Mars entered an opposition closer to Earth than at any time in the century before or the next 80 years. In the United States, a “National Radio Silence Day” was promoted during a 36-hour period from August 21–23, with all radios quiet for five minutes on the hour, every hour.
At the United States Naval Observatory, scientists used a radio receiver, miles above the ground in a dirigible, to listen for any potential radio messages from Mars.
A 1959 paper by Philip Morrison and Giuseppe Cocconi first pointed out the possibility of searching the microwave spectrum, and proposed frequencies and a set of initial targets.
In 1960, Cornell University astronomer Frank Drake performed the first modern SETI experiment, named “Project Ozma”, after the Queen of Oz in L. Frank Baum’s fantasy books. Drake used a radio telescope at Green Bank, West Virginia, to examine the stars Tau Ceti and Epsilon Eridani.
Soviet scientists took a strong interest in SETI during the 1960s and performed a number of searches. Soviet astronomer Iosif Shklovsky wrote the pioneering book in the field, Universe, Life, Intelligence (1962), which was expanded upon by American astronomer Carl Sagan as the best-selling book Intelligent Life in the Universe (1966).
In the March 1955 issue of Scientific American, John D. Kraus described an idea to scan the cosmos for natural radio signals using a radio telescope. Ohio State University soon created a SETI program.
In 1971, NASA funded a SETI study that involved Drake, Bernard M. Oliver of Hewlett-Packard Corporation, and others. The resulting report proposed the construction of an Earth-based radio telescope array with 1,500 dishes known as “Project Cyclops”. It was not built, but the report formed the basis of much SETI work that followed.
Why don’t any organisms detect radio waves?
Much life on earth can see in visible light. Some organisms can see IR (infrared) or UV (ultraviolet) light – but as far as we know none can see the radio part of the EM spectrum. Why not?
See Why don’t any organisms detect radio waves?
How difficult will this be?
It is very difficult to pick up Earth’s radio waves from another solar system. As such, we can imagine that it would very difficult to pick up radio waves here, from some other solar system.
That’s why we aren’t really looking for random radio waves that happen to escape out into space. Rather, the current projects are looking for much more powerful signals, that we hope would be sent out on purpose.
https://io9.gizmodo.com/are-we-screwing-ourselves-by-transmitting-radio-signals-493800730
“That’s a rather extraordinary claim, so I spoke to SETI expert and scifi novelist David Brin about it — and he’s not convinced detection is this easy. He told me that, even if an ETI had a one square kilometer array, they would have to point it a at Earth for the duration of an entire year. “
Because it would take that long,” he told io9. “But why stare if you don’t already have a reason to suspect?”
Like SETI Institute’s Seth Shostak, Brin believes that Earth is not detectable beyond five light years. “With one exception: Narrow-focused, coherent (laser-like) planetary radars that are aimed to briefly scan the surfaces of asteroids and moons,” he says, “
And not to be confused with military radars that disperse.””
How can we differentiate between natural or artificial (intelligent) signals?
Consider listening to the sound of radio static. Compare that to the sound of a song, or a person giving a speech. Both are sounds – how are they similar? How are they different?
Come up with ideas on how we could differentiate between natural or artificial (intelligent) signals.
“Humanity has received some odd signals in the past. We’ve also sent out some signals ourselves. How could we determine that a signal we’d received was artificial in origin? Or of course inversely, how could an extraterrestrial civilization determine a signal we had sent out was was artificial?”
Listening for Extraterrestrial Blah Blah: At the cosmic dinner party, intelligence is the loudest thing in the room. By Laurance R. Doyle, Illustrations by Tianhua Mao
Listening for Extraterrestrial Blah Blah
The Water hole: What radio frequencies should we listen to?
Tba
Hailing Frequencies Open, Captain! What is the “water hole”?
Misconceptions about listening with radio telescopes
Radio signals diminish in strength very rapidly with distance – they decrease according to the inverse square law. What does that mean?
Consider cooking oil that is sprayed. The cooking spray hits a piece of toast and deposits an even layer of butter, 1 mm thick.
Hewitt textbook
When the butter gets twice as far, it becomes only 1/4 as this.
If it travels 3 times as far, it will spread out to cover 3 x 3, or 9, pieces of toast.
So now the butter will only be 1/9th as thick. (1/9 is the inverse square of 3)
This pattern is called an inverse-square law.
The same is true for a can of spray paint: as the paint travels further, it covers a wider area, so the paint per area is inversely less thick.
Hewitt Conceptual Physics worksheets
The same pattern of spreading out and weakening, the inverse square laws, is true for radio waves.
Animations of the inverse-square law – animated clip: Inverse-square law for light
Okay – so by the time that radio signals reach even the next solar system they would be unbelievably weak. The radio signals would be even millions of times weaker by the time they travelled across even 1% of the galaxy.
Our radio telescopes could never pick up such radio signals.
So if that’s the case, what then are SETI researchers listening for?We are looking for a civilization that wants to be known, one that has deliberately built a high power radio beacon, aimed in one direction at a time.
A tightly beamed signal would be millions of times stronger – if by chance we happen to be in its path.
Do SETI researchers believe that someone out there is deliberately sending a signal to us here on Earth specifically? No. However, we know that there are billions of stars, and tens of billions of planets. Many of these planets might support life.
Therefore, at any given time there could be many thousands of other worlds with intelligent life. The hope is that some of them would want to communicate, sending a tight, beamed radio signal out into space. If so, then one day we might intercept such a communication.
Article: Is there anybody out there? Jason Davis, October 25, 2017, The Planetary Society Planetary.org – Is there anybody out there?
Goldilocks Zone/Circumstellar habitable zone
This section from evolution.berkeley.edu, A Place for Life: A special astronomy exhibit of Understanding Evolution
From the known properties of stars and of the chemistry of water, astronomers can define “habitable zones” around stars where liquid water (and hence life) could exist on the surface of planets.
Too close to the star, and water will boil; too far, and it will freeze. This so-called Goldilocks zone, where the temperature is just right, depends on both the distance from the star and the characteristics of the star itself.
The habitable zone around luminous giant stars is further from the star than the habitable zone around faint dwarfs.
Of course, as noted previously, life may also exist outside these zones, for example in subsurface oceans on icy moons heated from the moon’s interior.
We know that there are around 200 billion stars in our Galaxy. Recent research has revealed that most of them have planets, and that tens of billions of these planets are likely similar in size to Earth, made of rock, and orbit in their stars’ habitable zones.
The question that remains to be answered is what fraction of those potentially habitable worlds host life.
https://www.e-education.psu.edu/astro801/content/l12_p4.html
from the NASA Kepler Mission
https://en.wikipedia.org/wiki/Circumstellar_habitable_zone
https://www.nasa.gov/content/kepler-multimedia
Habitable Zones of Different Stars. NASA/Kepler Mission/Dana Berry.
https://www.nasa.gov/ames/kepler/habitable-zones-of-different-stars
Habitable zones for binary star systems
What about planets in a solar system with two stars?
Most stars in the Galaxy have at least one stellar companion—binary or multiple star systems. Stars like our Sun with no stellar companion are in the minority.
It would probably be difficult for there to be stable, only slightly elliptical planet orbits in a binary or multiple star system.
Complex life (multi-cellular) will need to have a stable temperature regime to form so the planet orbit cannot be too eccentric.
Simple life like bacteria might be able to withstand large temperature changes on a planet with a significantly elliptical orbit but complex life is the much more interesting case.
Suitable binary stars would be those systems where either:
(a) the binary stars orbit very close to each other with the planet(s) orbiting both of them at a large distance (called a “circumbinary planet”)
or (b) the binary stars orbit very far from each other so the planet(s) could reside in stable orbits near each of the stars—the one star’s gravity acting on a planet would be much stronger than that of the other star.
Image by Nick Strobel
image from https://www.astronomynotes.com/lifezone/s2.htm
A cool article on this subject: I Built a Stable Planetary System with 416 Planets in the Habitable Zone
Strong magnetic fields may be necessary
Earth has a strong magnetic field.
It turns out that this might be necessary on a planet if complex life is to evolve.
v
Why does Earth have such a strong magnetic field? Earth’s core is still hot and molten. Metal still moves inside it, and moving metal has moving free electrons.
Electrons moving around – by definition – are an electrical current. And it turns out that electrical currents create their own magnetic field!
Image from S-cool revision. GCSE » Physics » Magnetism and Electromagnetism
Inside the earth
This field protects the Earth’s atmosphere from some of the Sun’s radiation.
Without such a field most of a planet’s atmosphere is likely to be blown away into space, as happened to Mars.
Mars now has very little atmosphere, and its surface is constantly irradiated by solar radiation.
What else may be necessary for life to evolve?
How do tectonic plates make Earth hospitable to life?
The Drake Equation
An equation named after Frank Drake, who first summarized the things we need to know to answer the question, “how many possible extraterrestrial civilizations are out there?”
The equation breaks this complex question into small parts. The Drake Equation
Matthew Bobrowsky says “I introduce the Drake Equation not to actually estimate the number of technological civilizations in the Galaxy, but to provide an indication of the kinds of things to consider when deciding about the likelihood of finding life on another world.”
“It’s also interesting to note that the most uncertain factor in the Drake equation is the average lifetime of a technological civilization. We have no idea how long we (humans) will last, but I have an interesting discussion with students about the various ways — both natural (e.g., an asteroid impact) and by our own hands (e.g., global nuclear war) that our species could become extinct at any time.”
Astrobiology: Life elsewhere in the universe
Here we will link to lessons about the realistic possibility of life existing elsewhere in our galaxy, The idea is far more mainstream than most people realize.
Why would anyone think that it is likely that life would also evolve elsewhere in the universe?
(A) Why not? We have no data to assume otherwise.
(B) We do have enormous amounts of data available on what life on Earth is made of, and how it evolved over time. We have enormous amounts of data available on biochemistry and organic chemistry. enormous amounts of data available on how stars work and how planetary systems form.
The most common chemical elements in life are the most common elements in the universe
Discussions on how atoms naturally form molecules, including precursors to the organic molecules here on Earth
Evidence that this same chemistry happens elsewhere in the galaxy
Class discussion: What conditions would life need to evolve on another world?
What conditions would life need to evolve into advanced forms of life?
Even if advanced forms of life evolve, would they necessarily be able to develop technology?
Example: Dolphins and whales on earth have near human-like intelligence, awareness, and emotions, but they don’t have hands. They can’t manipulate their environment; can’t mine minerals or metals, and this can’t develop technology.
needs for energy – what possible energy sources?
needs for a solvent – water seems to be the only likely solvent, although we can investigate other options
protection from radiation (from stars, supernovas, et.)
how long would it take for life to evolve? How long are the lives of stars?
Given this, what kinds of stars could we expect to possibly have intelligent life?
(likely not around O-type stars, they burn out too quickly)
What kind of biochemistry would exist?
-
probably carbon based
-
we can investigate other possibilities
What kind of conditions could life thrive under? Consider conditions necessary for human life in specific, then animal life in general. Then compare to range of conditions that archaea can survive in.
Potential habitats for life
Terrestrial planets
Super Earths
Worlds like Europa, Enceladus
Atmosphere of brown dwarf stars
Alien life could thrive in the clouds of failed stars: cold brown dwarf stars
Cold brown dwarf star no hotter than a summer’s day
Atmospheric Habitable Zones in Y Dwarf Atmospheres, Jack S. Yates, Paul I. Palmer, Beth Biller, Charles S. Cockell , The Astrophysical Journal
Megastructures (Dyson swarms, etc.)
Evidence for ET intelligent life
None currently exists
UFO fads in the late 1800s, 1950s, and today. Extremely low quality photographs, evidence is considered at best very poor.
The WOW signal and other somewhat more realistic events that could be interpreted as evidence
Possible significant downside to contacting ET intelligence
TBA
Could we realistically ever travel to other star systems?
Here we learn about the potentially realistic physics of interstellar travel
Learning Standards
Common Core, English Language Arts Standards » Science & Technical Subjects
CCSS.ELA-LITERACY.RST.9-10.1 – Cite specific textual evidence to support analysis of science and technical texts, attending to the precise details of explanations or descriptions.
CCSS.ELA-LITERACY.RST.9-10.2 – Determine the central ideas or conclusions of a text; trace the text’s explanation or depiction of a complex process, phenomenon, or concept; provide an accurate summary of the text.
CCSS.ELA-LITERACY.RST.9-10.4 – Determine the meaning of symbols, key terms, and other domain-specific words and phrases as they are used in a specific scientific or technical context.
CCSS.ELA-LITERACY.RST.9-10.5 – Analyze the structure of the relationships among concepts in a text, including relationships among key terms (e.g., force, friction, reaction force, energy).
CCSS.ELA-LITERACY.RST.9-10.6 – Analyze the author’s purpose in providing an explanation, describing a procedure, or discussing an experiment in a text, defining the question the author seeks to address.
2016 Massachusetts Science and Technology/Engineering Curriculum Framework
HS-PS2-5. Provide evidence that an electric current can produce a magnetic field and that a changing magnetic field can produce an electric current.
6.MS-PS4-1. Use diagrams of a simple wave to explain that (a) a wave has a repeating pattern with a specific amplitude, frequency, and wavelength, and (b) the amplitude of a wave is related to the energy of the wave.
HS-PS4-1. Use mathematical representations to support a claim regarding relationships among the frequency, wavelength, and speed of waves traveling within various media. Recognize that electromagnetic waves can travel through empty space (without a medium) as compared to mechanical waves that require a medium.
HS-PS4-5. Communicate technical information about how some technological devices use the principles of wave behavior and wave interactions with matter to transmit and capture information and energy.
Next Generation Science Standards: Science & Engineering Practices
● Ask questions that arise from careful observation of phenomena, or unexpected results, to clarify and/or seek additional information.
● Ask questions that arise from examining models or a theory, to clarify and/or seek additional information and relationships.
● Ask questions to determine relationships, including quantitative relationships, between independent and dependent variables.
● Evaluate a question to determine if it is testable and relevant.
● Ask and/or evaluate questions that challenge the premise(s) of an argument, the interpretation of a data set, or the suitability of the design
Common Core Math Standards (Inverse-square law)
CCSS.Math.Content.7.RP.A.2a ( Grade 7 ): Decide whether two quantities are in a proportional relationship, e.g., by testing for equivalent ratios in a table or graphing on a coordinate plane and observing whether the graph is a straight line through the origin.
CCSS.Math.Content.7.RP.A.2c ( Grade 7 ): Represent proportional relationships by equations.
KaiserScience 