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NGSS Three dimensional learning

NGSS has three distinct components: 1. Disciplinary Core Ideas, 2. Cross Cutting Concepts, and 3. Science & Engineering Practices.


North Country 3D Science Cafe

NGSS Three Dimensional Learning

Teaching Channel NGSS 3 dimensional teaching

Three Dimensions of the Framework for K-12 Science Education Being Used to Develop the Next Generation Science Standards (NGSS)

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.


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:

  • Physical science
  • Life science
  • Earth and space science
  • Engineering, technology, and applications of science
Crosscutting Concepts

Applicable to all science disciplines, crosscutting concepts link the disciplines together.

  • Patterns
  • Cause and effect
  • Scale, proportion, and quantity
  • Systems and system models
  • Energy and matter: Flows, cycles, and conservation
  • Structure and function
  • Stability and change

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.





What is a “moon”?

Lunar libration with phase 2

Lunar libration with phase

Earth has a moon, Luna, but most of the other planets in our solar system also have moons.


(adapted from Wikipedia)

Interestingly, the Moon was called a “planet” until Copernicus’ publication of De revolutionibus orbium coelestium in 1543.

Until the discovery of the Galilean satellites around Jupiter, in 1610, there was no opportunity for referring to such objects as a class. Galileo chose to refer to his discoveries as Planetæ (“planets”.) It was only later discoverers who chose other terms to distinguish them from the objects they orbited.

The first to use of the term satellite to describe orbiting bodies was the German astronomer Johannes Kepler in his pamphlet Narratio de Observatis a se quatuor Iouis satellitibus erronibus (“Narration About Four Satellites of Jupiter Observed”) in 1610. Kepler derived the term from the Latin word satelles, meaning “guard”, or “companion”, because the satellites accompanied their primary planet in their journey through the heavens.

The term satellite became the normal one for referring to an object orbiting a planet, as it avoided the ambiguity of the word “moon”. In 1957, however, the launching of the artificial object Sputnik created a need for new terminology. The terms man-made satellite and artificial moon were very quickly abandoned in favor of the simpler satellite, and as a consequence, the term has become linked primarily with artificial objects flown in space – including, sometimes, even those not in orbit around a planet.

Because of this shift in meaning, the term “moon,” which had continued to be used in a generic sense in works of popular science and in fiction, has regained respectability and is now used interchangeably with natural satellite, even in scientific articles.

To avoid ambiguity, the convention is to capitalize the word Moon when referring to Earth’s natural satellite, but not when referring to other natural satellites.

Many authors define “satellite” or “natural satellite” as orbiting some planet or minor planet, synonymous with “moon” – by such a definition all natural satellites are moons, but Earth and other planets are not satellites.


Mars and its moons, 3D visualization



Pull out from Jupiter Showing Moon Orbits, showing 63 moons


Jupiter And The Galilean moons



Saturn and its major moons



Uranus and its major moons



Neptune and its major moon Triton


Neptune and its rings


Pluto and its moon Charon



Astronomical engineering: a strategy for modifying planetary orbits

How’s this for an idea for a science-fiction story?

The sun has unexpectedly started to swell into a red giant – which would engulf and destroy the Earth. So, “to save humanity, the world’s governments have banded together and constructed thousands of rocket engines across the Earth’s surface. Once installed, they propel the planet out of its solar system and onto a 2,500 year journey to resettle in Alpha Centauri.” (Grant Watson.)

The Wandering Earth (Chinese: 流浪地球) is a 2019 Chinese science fiction film directed by Frant Gwo, loosely based on the novella of the same name by author Liu Cixin. Here’s an image of one of the many “Earth Engines.”

The Wandering Earth Movie (Engine)

Our question – Could this be done in real life?

What science in the film did they get right or wrong?

Helium flash

thrusting the Earth out of orbit with rockets

How much mass would we need to do this?

Even if you could build engines large enough, mining the Earth (as these engines do in the film) causes a problem. There would barely be any Earth left by the point you mined enough dirt to thrust the planet to Proxima Centauri, 4.2 light-years away. “It would take about 95 percent of the mass of Earth to do this,” Elliott estimates.

Stopping the rotation of the Earth?

Gravitational slingshot around Jupiter

Surviving the radiation around Jupiter

Could ‘The Wandering Earth’ Actually Happen? Here’s What a NASA Engineer Says

Wandering Earth: Rocket scientist explains how we could move our planet. ARS Technia

Other options

Move human civilization to Mars, which become habitable

In principle, how could we actually move the Earth?

Astronomical engineering: a strategy for modifying planetary orbits
D. G. Korycansky, Gregory Laughlin, Fred C. Adams (7 Feb 2001)

The Sun’s gradual brightening will seriously compromise the Earth’s biosphere within ~ 1E9 years. If Earth’s orbit migrates outward, however, the biosphere could remain intact over the entire main-sequence lifetime of the Sun.

In this paper, we explore the feasibility of engineering such a migration over a long time period. The basic mechanism uses gravitational assists to (in effect) transfer orbital energy from Jupiter to the Earth, and thereby enlarges the orbital radius of Earth.

This transfer is accomplished by a suitable intermediate body, either a Kuiper Belt object or a main belt asteroid. The object first encounters Earth during an inward pass on its initial highly elliptical orbit of large (~ 300 AU) semimajor axis. The encounter transfers energy from the object to the Earth in standard gravity-assist fashion by passing close to the leading limb of the planet. The resulting outbound trajectory of the object must cross the orbit of Jupiter; with proper timing, the outbound object encounters Jupiter and picks up the energy it lost to Earth.

With small corrections to the trajectory, or additional planetary encounters (e.g., with Saturn), the object can repeat this process over many encounters. To maintain its present flux of solar energy, the Earth must experience roughly one encounter every 6000 years (for an object mass of 1E22 g). We develop the details of this scheme and discuss its ramifications.


As for the Moon, reasoning by analogy with cases of stellar binaries and third-body encounters suggests that the Moon will tend to become unbound by encounters in which O passes inside the Moon’s orbit. (As well, there is the non-zero probability of collisions between O and the Moon, which must be avoided.) Again, detailed quantitative work needs to be done, but it seems that the Moon will be lost from Earth orbit during this process. On the other hand, a subset of encounters could be targeted to “herd” the Moon along with the Earth should that prove necessary.

It has been suggested (cf. Ward and Brownlee, 2000) that the presence of the Moon maintains the Earth’s obliquity in a relatively narrow band about its present value and is thus necessary to preserve the Earth’s habitability. Given that the Moon’s mass is 1/81 that of the Earth, a similarly small increment of the number of encounters should be sufficient to keep it in the Earth’s environment.

The fate of Mars in this scenario remains unresolved. By the time this migration question becomes urgent, Mars (and perhaps other bodies in the solar system) may have been altered for habitability, or at least become valuable as natural resources. Certainly, the dynamical consequences of significantly re-arranging the Solar System must be evaluated. For example, recent work by Innanen et al. (1998) has shown that if the Earth were removed from the Solar System, then Venus and Mercury would be destabilized within a relatively short time. In addition, the Earth will traverse various secular and mean-motion resonances with the other planets as it moves gradually outward. A larger flux of encounters might be needed to escort the Earth rapidly

Journal reference: Astrophys.Space Sci.275:349-366,2001
Astronomical Engineering: A Strategy For Modifying Planetary Orbits, Springer Link
Cite as: arXiv:astro-ph/0102126
(or arXiv:astro-ph/0102126v1 for this version)

The water cycle and atmospheric rivers

From NOAA, National Oceanic and Atmospheric Administration

The water cycle is often taught as a simple circular cycle of evaporation, condensation, and precipitation.

Although this can be a useful model, the reality is much more complicated. The paths and influences of water through Earth’s ecosystems are extremely complex and not completely understood.


Image from NOAA, National Oceanic and Atmospheric Administration

Liquid water evaporates into water vapor, condenses to form clouds, and precipitates back to earth in the form of rain and snow.

Water in different phases moves through the atmosphere (transportation).

Liquid water flows across land (runoff), into the ground (infiltration and percolation), and through the ground (groundwater).

Groundwater moves into plants (plant uptake) and evaporates from plants into the atmosphere (transpiration).

Solid ice and snow can turn directly into gas (sublimation).

The opposite can also take place when water vapor becomes solid (deposition).

Atmospheric river

from the NOAA website

Atmospheric rivers are relatively long, narrow regions in the atmosphere – like rivers in the sky – that transport most of the water vapor outside of the tropics.

Atmospheric River GIF

These columns of vapor move with the weather, carrying an amount of water vapor roughly equivalent to the average flow of water at the mouth of the Mississippi River. When the atmospheric rivers make landfall, they often release this water vapor in the form of rain or snow.

North America from space

Although atmospheric rivers come in many shapes and sizes, those that contain the largest amounts of water vapor and the strongest winds can create extreme rainfall and floods, often by stalling over watersheds vulnerable to flooding.

These events can disrupt travel, induce mudslides and cause catastrophic damage to life and property.

A well-known example is the “Pineapple Express,” a strong atmospheric river that is capable of bringing moisture from the tropics near Hawaii over to the U.S. West Coast.

Not all atmospheric rivers cause damage; most are weak systems that often provide beneficial rain or snow that is crucial to the water supply. Atmospheric rivers are a key feature in the global water cycle and are closely tied to both water supply and flood risks — particularly in the western United States.




Difference between weather and climate

From The National Center for Atmospheric Research and UCAR Office of Programs


Weather radar

What is the difference between weather and climate? Weather is what the forecasters on the TV news predict each day. They tell people about the temperature, cloudiness, humidity, and whether a storm is likely in the next few days.

Weather is the mix of events that happens each day in our atmosphere. Weather is not the same everywhere. It may be hot and sunny in one part of the world, but freezing and snowy in another.

Climate is the average weather in a place over many years.

While the weather can change in just a few hours, climate takes hundreds, even thousands of years to change.

Explanation by Neil deGrasse Tyson

From Neil deGrasse Tyson ShowsWeather Is Not Climate With One Very Simple Demonstration, The Huffington Post, Sarah Barness


“Weather is what the atmosphere does in the short-term, hour-to-hour, day-to-day,” the “Cosmos” host explains in the clip above. “Weather is chaotic, which means that even a microscopic disturbance can lead to large scale changes. That’s why those 10-day weather forecasts are useless … Climate is the long-term average of the weather over a number of years. It’s shaped by global forces that alter the energy balance in the atmosphere, such as changes in the sun, tilt of the Earth’s axis, the amount of sunlight the Earth reflects back into space and the concentration of greenhouse gasses in the air.”

Weather Versus Climate Change | Cosmos: A Spacetime Odyssey (YouTube)

[In this video] Tyson compares weather to the irregular, sporadic pattern of his dog. Though it’s difficult to predict where the dog is going, we can know the range of his meandering because he’s on a leash. Conversely, Tyson’s straight path is like the climate, which is broadly predictable by observing long-term changes in global forces. Both man and dog have their own patterns, but both are going in the same direction.



How reliable are genetic ancestry tests?

How reliable are genetic ancestry tests/genealogical DNA testing?

Ancestry report 23andme family

Sample report from 23AndMe


What is the technology?


Why would people want to do this?

Learn about family history

Learn about susceptibility to diseases (Parkinson’s, Cancer)

Predicting Side Effects of Pharmaceuticals

Are we really of only the heritage that we think we are from?

If you’re black, DNA ancestry results can reveal an awkward truth, Splinter News, 2016

What companies are offering these tests?

  • 23andMe, personal genomics and biotechnology company, Mountain View, CA

  • Affymetrix

  • AncestryDNA

  • Family Tree DNA

  • MyHeritageDNA

Ethical issues


genetic counseling

Example: Tay Sachs

Five Things to Know about Direct-to-Consumer Genetic Tests. Johns Hopkins Medicine.

Alzheimer’s Society’s view on genetic testing

How reliable is the interpretation of the data?

Intro tba

How DNA Testing Botched My Family’s Heritage, and Probably Yours, Too, Gizmodo, 2018

How Accurate Are Online DNA Tests? Scientific American

Genetic tests are everywhere, but how reliable are they? Boston Globe

Pulling Back the Curtain on DNA Ancestry Tests. Tufts University

What genetic tests from 23andMe, Veritas and Genos really told me about my health. Science News

What I actually learned about my family after trying 5 DNA ancestry tests. Results Vary Wildly. Science News

Articles from scientific journals

False-positive results released by direct-to-consumer genetic tests highlight the importance of clinical confirmation testing for appropriate patient care. Nature, 2018

How is genetic testing evaluated? A systematic review of the literature. European Journal of Human Genetics, 2018

Why is the interpretation of the data often wrong?

The accuracy of the interpretations will get better over time. But for now they are not great. Why not?

Kristen V. Brown writes:

Four tests, four very different answers about where my DNA comes from—including some results that contradicted family history I felt confident was fact. What gives?

There are a few different factors at play here. Genetics is inherently a comparative science: Data about your genes is determined by comparing them to the genes of other people.

As Adam Rutherford, a British geneticist and author of the excellent book “A Brief History of Everyone Who Ever Lived,” explained to me, we’ve got a fundamental misunderstanding of what an ancestry DNA test even does.

“They’re not telling you where your DNA comes from in the past,” he told me, “They’re telling you where on Earth your DNA is from today.”

Ancestry, for example, had determined that my Aunt Cat was 30 percent Italian by comparing her genes to other people in its database of more than six million people, and finding presumably that her genes had a lot of things in common with the present-day people of Italy.

Heritage DNA tests are more accurate for some groups of people than others, depending how many people with similar DNA to yours have already taken their test. Ancestry and 23andMe have actually both published papers about how their statistical modeling works.

As Ancestry puts it: “When considering AncestryDNA estimates of genetic ethnicity it is important to remember that our estimates are, in fact, estimates. The estimates are variable and depend on the method applied, the reference panel used, and the other customer samples included during estimation.”

That the data sets are primarily made up of paying customers also skews demographics. If there’s only a small number of Middle Eastern DNA samples that your DNA has been matched against, it’s less likely you’ll get a strong Middle Eastern match.

from gizmodo How-dna-testing-botched-my-familys-heritage-and-probably yours, 2018

Further reading

Understanding genetic testing: U.S. National Library of Medicine


Learning Standards

HS-LS1-1. Construct a model of transcription and translation to explain the roles of DNA and RNA that code for proteins that regulate and carry out essential functions of life.

HS-LS3-1. Develop and use a model to show how DNA in the form of chromosomes is passed from parents to offspring through the processes of meiosis and fertilization in sexual reproduction.

HS-LS3-2. Make and defend a claim based on evidence that genetic variations (alleles) may result from (a) new genetic combinations via the processes of crossing over and random segregation of chromosomes during meiosis, (b) mutations that occur during replication, and/or (c) mutations caused by environmental factors. Recognize that mutations that occur in gametes can be passed to offspring.

HS-LS3-3. Apply concepts of probability to represent possible genotype and phenotype combinations in offspring caused by different types of Mendelian inheritance patterns.

HS-LS3-4(MA). Use scientific information to illustrate that many traits of individuals, and the presence of specific alleles in a population, are due to interactions of genetic factors
and environmental factors.


Black holes: Videos

A CURIOUS WORLD: BLACK HOLES: What are black holes made of and how do they work?


NOVA search


Rebuilding the Interstellar Black Hole


Black holes are not as black as we once thought. They are theorized to die a slow death by evaporation, emitting energy known as Hawking radiation.


What’s inside a black hole?


Four types of black holes


PBS NOVA: Black Hole Apocalypse. Season 45, Episode 1

“Black holes are the most enigmatic and exotic objects in the universe. They’re also the most powerful, with gravity so strong it can actually trap light. And they’re destructive. Anything that falls into them vanishes…gone forever. But now, astrophysicists are realizing that black holes may be essential to understanding how our universe unfolded.”




Black hole eating a star GIF