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With this activity students will use planetary maps to compare the environmental conditions of Pluto and its moon Charon to those on Earth. They will understand the conditions needed for life to exist, and be able to explain why it cannot exist on Pluto or Charon.
What is this activity about? Astrogeology . It is about the geography / geology of planets , and about how to read and make maps (cartographic representation). At elementary school level, the concept of “geography” (that can be a part of the more general “Science” curriculum) covers basic concepts of several fields in Earth and Atmospheric Sciences, for example geology, geomorphology, cartography, meteorology and climatology. We follow this concept.
What is this activity NOT about? This activity is not a planetary science image interpretation practice. This is also not an introduction to the structure of the Solar System or Astronomy. Astronomy is a completely different discipline from planetary science. The subject of Planetology is planetary bodies, and an important part of it is called astrogeology , which studies the surface geology of planets and moons. This activity is an astrogeologic and planetary cartographic activity. Astronomy is about for example stars, galaxies, and the celestial motions of planets.
Cartographic problems: The map shows Pluto and Charon in Lambert Projection (a separate hemispheric view of each body). The Southern Hemispheres of both bodies are shown in darkness, as they were in darkness when the New Horizons probe flew by, so could not be imaged very well. The other sides of Pluto and Charon were not imaged as the probe only flew past one side of the binary system.
Astrobiology: About “alien” creatures: On the map, every geologic feature shown is real and placed at their true position, however the living creatures are completely fictional which also requires the teacher’s explanation so that the students will not think that people or “aliens” live on planets and moons. It should be clarified that no life or sign of past life has ever been identified on any planet or moon other than on Earth. This might be a good opportunity to talk about the billions of exoplanets that exist in the universe that, unlike most extra-terrestrial Solar System planets and moons, include millions of planets and moons where conditions are much more favourable for life than extra-terrestrial worlds within our Solar System. An exciting new part of planetary science is exoplanetology, which deals with planets outside our Solar System. Many of those exoplanets and exomoons are completely different from those in our Solar System. The very basis of space missions is to search for life. On Mars, scientists are looking for places where life could have developed in the past or may have survived in geologic refuges (caves, in the subsurface, within rocks, water-containing layers etc.). This is why NASA was looking for signs of water. Now that water (ice) containing sites and geologic units have been identified, they are searching for signs of past or present life. Europa may have a subsurface ocean that is exposed to space in new fractures. Scientist today are looking for life forms that are based on the same materials as terrestrial life, i.e. carbon-based life that relies on water, so they are looking for places where water can exist in liquid form. Other forms of life may exist, however as we do not know about them or how to identify them, the main focus is searching for identifiable carbon-based life.
About space programs: In addition to search for life, or bodies and regions that are habitable for terrestrial-like life, space programs are also motivated by the competition between countries. Space exploration also helps understand the geological processes on our planet and Earth’s past and future. For example, the intense greenhouse effect on Venus can help predict similar processes in Earth’s future or impact craters show how the Earth looked like 4 billion years ago. One of the most unexpected results of the Apollo program that sent humans on to the Moon was the so-called “overview effect”: this was the first – and so far, last – time when human eyes saw our planet as a fragile “blue marble” against the black space that changed our perception of our world and our place in the universe.
About space research: Individual scientists can do research on a single landform for years, trying to explain how and when it formed. Others map specific regions in detail and classify the features seen on the maps. After a scientist publishes the results of the research, it becomes a little brick in the large building of planetary science and other scientists can use these results to improve their surface evolution models or can use these results in their own research. Most of the content shown on these maps were obtained in the last decades, in some cases, only in recent years. The formation of some landforms is still not fully understood.
Body type: Planet or moon. Planets orbit the Sun, moons orbit a planet. One side of a moon generally always faces its planet (tidally locked).Body composition: Rocky bodies are made of silicate rocks (example Earth). Icy bodies are made of a rock and H2O ice mixture but their surfaces are usually mostly ice (example: Europa). On these worlds mountains and plains are made of rock-hard ice. Icy bodies occur only in the colder Outer Solar System. Atmosphere: Atmospheres only occur if the gravity (and size) of the body is sufficient to hold gas molecules. It is easier to hold a gas molecule if it is colder. Liquid: Liquids may be water in the inner Solar System or methane-ethane-nitrogen in the Outer Solar System. Liquids only occur where there is an atmosphere that produces air pressure. If air pressure is too low, liquid molecules evaporate/sublimate. If temperature is too low, liquids freeze. If temperature is too high, liquids evaporate. Water may exist underground. Weather: Diurnal temperature range (changes in temperature due to day and night) and forms of precipitation. Endogenic features: Features produced by forces in the interior of the planet. Volcanism requires molten interior. Heat is provided from planetary formation (impact / accretion heat) or the irreversible decay of radioactive elements. Small bodies cool quicker than large bodies, so volcanism is found only on larger planets. An exception is if the interior is continuously heated. This happens inside moons on elliptic orbits where tidal forces produce interior heat (e.g. Io). Tectonic features are caused by stresses in the brittle crust. Tectonic forces produce fractures during earthquakes. This requires movements within the planet, also driven by internal heat. Volcanoes grow upward by adding more lava but may collapse and produce crater-like caldera. Exogenic features: Features produced by processes on the surface or atmosphere. Includes aeolian (wind), fluvial (river), lacustrine (lake), oceanic features and their deposits. Cosmogenic features: Features produced by impacting bodies (smaller craters and larger impact basins). Younger craters have radial rays (produced by ejected materials) Common features: The most common features are craters. Most craters were formed soon after the Solar System formed and still had many small bodies in space. Craters are rare on surfaces that have been resurfaced recently, because resurfacing removes or buries craters. Resurfacing processes include volcanic plains, fluvial erosion and sedimentation, and subduction by plate tectonics. Rare/Special Features: Features not found in many other places, they may be caused by very specific atmospheric/climate conditions or a remnant of an unusual event in the bodies past. Life limiting parameter: Life should be able to grow and reproduce. Life may be limited by below freezing or above boiling temperatures, lack of atmosphere, lack of water or lack of magnetosphere (magnetospheres protect bodies from dangerous radiation in solar winds). Nomenclature (Naming): Placenames can be proposed by the scientists who study a region or feature and it is approved by the working group of the International Astronomical Union’s specialized to planetary placenames. Each feature type and each body has a particular theme (for example, gods of fire for Io) and the generic terms (like Mountain) are in Latin language to ensure language-neutrality. This also follows the geographic traditions of the 1600s when the first maps of the Moons were created in Europe with Latin names.Age: Age of the surface. Many craters on the surface indicates an old surface age (4 billion years old), fewer craters indicates a younger surface age (0-3 billion years old). In the early solar system (c. 4 billion years ago) there were many small objects that could impact on the bodies causing craters. Later on, there were far fewer objects as they had impacted onto the planets or been moved away by their gravitational fields.
Shapes of geologic features:Circular: usually an impact crater, occasionally a volcanic calderaLinear (straight): negative elevation = tectonic fracture, positive elevation = dune, ridge or mountainSinuous: river or lava channelLobate: water rich impact crater, ejecta (debris thrown out by an impact or volcano), glacier, landslideRadial: impact crater rayConcentric: impact crater ring
Earth for comparison: (MAP: use http://countrymovers.elte.hu/countrymovers.html for Earth map or Google map).
Body type: planetBody composition: rockyAtmosphere: just rightLiquid: waterEndogenic features: volcanoes, faults. Plate tectonics is unique to Earth.Exogenic features: rivers, lakes, dunes, floodplains, deltas, glaciers. Glacial features on Earth are not permanent, most of the time there is no ice cap on Earth.Cosmogenic features: 100+ impact craters, many buried or eroded due to erosion, or destroyed by plate tectonics (subduction), or impacted into water without permanent crater. Common features: oceans, mountains, plains, rivers Rare features: glaciers Life limiting parameter: where it is too dry (no liquid water - deserts), too cold (no liquid water – Antarctica) Age: mostly very young, some as old as 1 billion years.
L'insegnante dispone di una mappa di Plutone e Caronte stampata in modo da essere leggibile ed accessibile agli studenti, oppure proiettata alla massima risoluzione.
Da qui si può scegliere uno o più dei seguenti sottoargomenti progettati per un’attività in classe con o senza opuscolo, o su può seguire le indicazioni dell’opuscolo così com'è.
Leggere la Pagina 1 dell'opuscolo con gli studenti, chiedendo loro di sottolineare le parole che non capiscono, così che gliele si possano spiegare.
Mostrare la mappa agli studenti e chiedere loro perché la rappresentazione del corpo è circolare (il pianeta è un corpo sferico). Spiegare che il sistema solare è stato visitato da una sonda (New Horizons) solo una volta, e che si può vedere solo un lato di ogni corpo, e inoltre gli Emisferi Sud erano in ombra.
Activity 1: - Draw the Equator (a horizontal line in the middle of the two circles), - Mark the poles - Write the name of the body as a map title.
Confrontare la rappresentazione cartografica con una vera fotografia (vedere figura 1 sull'opuscolo). Notare le differenze tra le due immagini. E' stata usata la generalizzazione cartografica (semplificazione) e si pone particolare enfasi sugli importanti, anche se non visibilmente prominenti, rilievi. Per i pianeti con atmosfera opaca, la superficie non è visibile dalla foto. I colori della mappa potrebbero essere diversi da quelli reali. Quali elementi non sono sulla foto, ma sono presenti sulla mappa? Perchè sono necessari tali elementi? (NB: gli alieni NON SONO REALI)
Chiedere alla classe quali informazioni geologiche (riguardo la morfologia) possono vedere sulla mappa. Nominare almeno uno dei tipi di formazione geologica (Vedere Attività 2 sull'opuscolo per una lista). Identificare/trovare le formazioni endogene che sono state prodotte dal magma che si trova sotto la superficie (formazioni vulcaniche: vulcani, flussi di lava. formazioni tettoniche: crepe, fratture). Identificare/trovare le formazioni esogene prodotte da processi che operano sulla superficie in un pianeta con atmosfera (vento: dune, deserti. acqua: agenti atmosferici, oceani, laghi, sedimenti). Identificare/trovare formazioni cosmogeniche prodotte da processi di impatto (crateri o bacini di impatto creati da asteroidi o comete provenienti dallo spazio).
Identify/find endogenic landforms that were produced by magma from below the surface (volcanic landforms: volcanoes, lava flows, tectonic landforms: cracks, fractures). Identify /find exogenic landforms that were produced by processes that operate on the surface in a planet with atmosphere (wind: dunes, deserts, water: weathering, rivers, oceans, lakes, sediments). Identify /find cosmogenic landforms that were produced by impact processes (impact craters or impact basins made by asteroids or comets coming from outer space).
Activity 2 - Graphic map. Using the map, draw a generalized (simplified) sketch map, showing the outlines of only the largest and most important features (draw several types of features, e.g., cracks and craters). You can use colors and/or lines. Try to include the following featurs:
Pluto (left circle) - Glacial: "Heart" shaped frozen nitrogen ice plains (Sputnik Planitia) with cellular terrain and ice mountain peaks - Southern dark-red coated regions - impact craters - tectonic cracks
Charon (right circle) - Tectonic – Equatorial deep chasms - Cosmogenic – North Polar red spot (red material coming from Pluto) - Impact: Few rayed craters, non rayed craters everywhere
Ask students where would they land / build a settlement(s) for more exploration? Which region (or feature) is worth more exploration? Why? What do you want to investigate? What instruments/tools/methods would you use for the investigation? What would you bring with you for this research?
Activity 3 - Your landing site. Where would you land? Which place you find the most exciting for exploration? Find YOUR landing site. Mark it with a symbol. Name your landing site (s). Write down the names next to the symbol.
Ask students to read one name from the map aloud. Ask what they understand from them, i.e. what the names tell them. The names are in Latin as the planets are not part of any country and Latin is considered a neutral international language. Ask students if they like this “neutral” (Latin) naming or name in English (or your language) would be better. You may explain the meaning of the names on the map. You can find the English equivalents in this site: http://planetarynames.wr.usgs.gov/DescriptorTerms
Activity 4 - Names. After the graphic part is finished, create the nomenclature: write the names of the features you have drawn next to the feature itself. Write three names (you can add more later) onto the map. You can use different colors or letters for each feature type (e.g, capital letters for continents, red color for the lava channel etc. -- be consistent).
Attività 5 : Previsioni meteo per domani, basate sulle informazioni climatiche sull'opuscolo. Scegliere almeno tre posti e mostrare i dati meteo. Mostrare le temperature massima e minima nella vostra unità di misura (C o F). Considerare il fatto che più si va verso i poli, più è freddo. Accanto ai numeri, mostrare il clima con un simbolo grafico disegnato da voi: soleggiato, nuvoloso, piovoso, nebbioso o altri fenomeni meteorologici interessanti che trovate sull'opuscolo. Trovare i dati sulle temperature massime e minime sul banco di controllo della mappa e informazioni ulteriori.
Chiedere agli studenti di che tipo di protezioni avrebbero bisogno se esplorassero la superficie fuori dal veicolo, basandosi sui valori precedentemente discussi. Ad esempio, potrebbero aver bisogno di bombole di ossigeno, una tuta che mantenga la temperatura e la pressione ottimale, etc.
Attività 6 : Disegnare una bandiera (per Plutone, Caronte o per entrambi), e disegnarla sulla mappa, basandosi sulle caratteristiche del corpo (clima, colore, geologia, ecc).
Activity 5 - Weather forecast for "tomorrow", based on the Weather information in the handout. Choose at least three places, and show weather data: display the min/max temperature in your unit (C or F) with LARGE numbers. Consider that on towards the poles it is colder. Next to the numbers, show the weather with a graphic symbol you design: clear (sunny), cloudy, rainy, foggy or any interesting, special weather phenomenon you learn from the handout. Find min/max temperature data on the map's control desk and additional information on the handout.
Didascalie
Activity 6 - (Design a flag (either for Pluto, Charon, or for both as one), and draw it on the map, based on the characteristics of the body (weather, color, geology etc).
Compito per casa: chiedere agli studenti di comporre o disegnare storie usando i paesaggi della mappa come ambientazione, e le creature come personaggi. Possibile trama: come ha fatto la superficie a diventare così com’è adesso? (con una storia, non scientificamente). Potreste anche illustrare la storia.
Activity 7 – Draw a legend where YOUR symbols are explained on the map. You may group them by process (e.g., exogenic (atmospheric, aeolian), endogenic (volcanic, tectonic) and impact processes). Write down the title “LEGEND” and explain your symbols and indicate which feature it corresponds to.
Homework: Ask students to compose or draw stories using the map’s landscapes as background for the story, and their creatures as the characters of the story. A possible storyline: how the surface became like what it is now? (as told with a story, not scientifically). You can also Illustrate the story.
For evaluation, fill out the Worksheet.Sample questions for evaluation:
