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Earth in Space Unit Overview

Unit Summary

 

This unit focuses on the composition of the universe and its scale of space and time, the principles on which the universe seems to operate, and how our modern view of the universe has emerged over time.

 

The unit begins with an exploration into the size and scale of the universe starting with our solar system and the Earth-Sun-Moon system.  This is followed by investigations on the forces that govern the movement of objects on Earth and in space and how our understanding of these forces came to be. You then explore the composition of solar system objects, the life and death of stars and how we understand these phenomena. Finding out the conditions that make Earth a habitable planet is explored next along with the technology we use to investigate the universe and the limits to our current understanding.

 

Big Ideas

 

Astronomy

 

  • Earth exists in the solar system, in the Milky Way galaxy, and in the universe, which contains many billions of galaxies.
  • The relative position and movements of Earth, the moon, and sun account for day and night, lunar and solar eclipses, the observed moon phases, tides, and seasons.                 
  • Some stars explode, producing clouds containing heavy elements from which other stars and planets orbiting them could later condense. The process of star formation and destruction continues. 4A/H2ef
  • Eight planets of very different size, composition, and surface features move around the sun in nearly circular orbits. Some planets have a variety of moons and even flat rings of rock and ice particles orbiting around them.
  • Some of these planets and moons show evidence of geologic activity. The earth is orbited by one moon, many artificial satellites, and debris. 4A/M3
  • The moon's orbit around the earth once in about 28 days changes what part of the moon is lighted by the sun and how much of that part can be seen from the earth- the phases of the moon. 4B/M5
  • Earth is the only body in the solar system that appears able to support life.
  • The other planets have compositions and conditions very different from the earth's. 4B/M2cd
  • The sun is a medium-sized star located near the edge of a disc-shaped galaxy of stars, part of which can be seen as a glowing band of light that spans the sky on a very clear night. 4A/M1a
  • The universe contains many billions of galaxies, and each galaxy contains many billions of stars. To the naked eye, even the closest of these galaxies is no more than a dim, fuzzy spot. 4A/M1bc
  • The sun is many thousands of times closer to the earth than any other star.
  • Light from the sun takes a few minutes to reach the earth, but light from the next nearest star takes a few years to arrive. The trip to that star would take the fastest rocket thousands of years. 4A/M2abc
  • Some distant galaxies are so far away that their light takes several billion years to reach the earth. People on earth, therefore, see them as they were that long ago in the past. 4A/M2de
  • Telescopes reveal that there are many more stars in the night sky than are evident to the unaided eye, the surface of the moon has many craters and mountains, the sun has dark spots, and Jupiter and some other planets have their own moons. 10A/M2

 

Energy

 

  • There are a great variety of electromagnetic waves: radio waves, microwaves, infrared waves, visible light, ultraviolet rays, X-rays, and gamma rays. These wavelengths vary from radio waves, the longest, to gamma rays, the shortest. 4F/M8** (BSL)
  • Whenever energy appears in one place, it must have disappeared from another. Whenever energy is lost from somewhere, it must have gone somewhere else. Sometimes when energy appears to be lost, it actually has been transferred to a system that is so large that the effect of the transferred energy is imperceptible. 4E/M1*
  • Energy can be transferred from one system to another (or from a system to its environment) in different ways: 1) thermally, when a warmer object is in contact with a cooler one; 2) mechanically, when two objects push or pull on each other over a distance; 3) electrically, when an electrical source such as a battery or generator is connected in a complete circuit to an electrical device; or 4) by electromagnetic waves. 4E/M2*
  • Thermal energy is transferred through a material by the collisions of atoms within the material. Over time, the thermal energy tends to spread out through a material and from one material to another if they are in contact. Thermal energy can also be transferred by means of currents in air, water, or other fluids. In addition, some thermal energy in all materials is transformed into light energy and radiated into the environment by electromagnetic waves; that light energy can be transformed back into thermal energy when the electromagnetic waves strike another material. As a result, a material tends to cool down unless some other form of energy is converted to thermal energy in the material. 4E/M3*
  • Energy appears in different forms and can be transformed within a system. Motion energy is associated with the speed of an object. Thermal energy is associated with the temperature of an object. Gravitational energy is associated with the height of an object above a reference point. Elastic energy is associated with the stretching or compressing of an elastic object. Chemical energy is associated with the composition of a substance. Electrical energy is associated with an electric current in a circuit. Light energy is associated with the frequency of electromagnetic waves. 4E/M4*
  • Light and other electromagnetic waves can warm objects. How much an object's temperature increases depends on how intense the light striking its surface is, how long the light shines on the object, and how much of the light is absorbed. 4E/M6**

 

 

Force and Motion

 

  • All matter has gravity and inertia.
  • Gravity and inertia play a major role in the formation and motion of celestial objects.
  • An object’s inertia causes it to continue moving the way it is moving unless it is acted upon by a force to change its motion. (CT)
  • The motion of an object can be described by its position, direction of motion and speed. (CT)
  • The change in motion (direction or speed) of an object is proportional to the applied force and inversely proportional to the mass. 4F/H1*
  • Whenever one thing exerts a force on another, an equal amount of force is exerted back on it. 4F/H4
  • Objects moving in circles must experience force acting toward the center.
  • Energy exists in different forms, and cannot be created or destroyed.
  • In most familiar situations, frictional forces complicate the description of motion, although the basic principles still apply. 4F/H7** (SFAA)
  • If a force acts towards a single center, the object's path may curve into an orbit around the center. 4F/M3b

 

 

Matter

 

  • All things are made of matter, having mass and volume
  • About 100 different elements have been identified, from which all matter (living and nonliving things on Earth) is made.
  • The physical and chemical properties of matter are determined by its composition.
  • Matter and energy cannot be created or destroyed, but they can change from one form to another.
  • Substances can be pure or mixtures
  • The atoms of any element are like other atoms of the same element, but are different from the atoms of other elements. 4D/M1b*

 

 

Engineering

 

  • The Engineering Design Process is an effective tool for solving a variety of engineering problems
  • A system is a group of interacting, interrelated, or interdependent elements forming a complex whole
  • The form of a structure (or its parts) is determined by its function and may be affected by the environment. (For example, the design and materials used in houses throughout the world differs based on the climate & environment.)
  • Materials have different characteristics or properties (e.g., shape, flexibility, texture, color, texture, hardness, color)
  • Objects may be made of different materials depending on the object’s use and the properties required (e.g., strength, hardness, flexibility, etc.)
  • Strength and stability can be enhanced depending on the way a material is used (e.g., the use of triangles in bridges and skyscrapers)
  • Many variables (materials, forces, earth composition, structural design) determine the stability of a structure.

 

 

 

 

Content Learning Expectations 

 

Astronomy

 

  • Use Earth's daily rotation to explain that the sun, moon, and stars all appear to rise and set. 
  • Recognize that gravity keeps the moon in orbit around Earth and Earth in orbit around the sun.
  • Use a celestial model to illustrate and explain how the relative position and size of the sun, Earth, and moon result in the phases of the moon and eclipses (lunar and solar) as observed from the Earth.
  • Compare and contrast properties and conditions of objects in the solar system (i.e., sun, planets, and moons) to those on Earth (i.e., gravitational force, distance from the sun, speed, movement, size, temperature, and atmospheric conditions).
  • Explain how Earth's tilt and its revolution around the sun result in an uneven heating of the earth, which in turn causes the seasons.
  • Use informational texts to illustrate that the stars visible in the night sky are a small part of the Milky Way Galaxy, one of many billions of galaxies in the Universe.
  • Recognize that all objects have a gravitational pull and the magnitude of the force between objects is dependent upon their mass and their distance apart.
  • Differentiate observations determined by Earth’s rotation (e.g., day and night) and observations determined by Earth’s orbit (e.g., changes in observed star patterns).
  • Attribute global temperature patterns to the sun’s observed path and the length of day.

 

 

Energy

 

  • Differentiate between stored energy and energy of motion. Identify situations where energy of motion is transformed into stored energy and vice versa (MA)
  • Collect and analyze data that shows that adding or taking away heat energy from a system can result in a temperature change (MA)
  • Explain the effect of heat on particle motion through a description of what happens to particles during a change in phase (MA)
  • Present examples of how heat transfers in predictable ways, moving from warmer objects to cooler ones (MA)
  • Identify the basic types of energy (light, sound, thermal, elastic, chemical, electrical, magnetic, gravitational, and kinetic) and relate each to their observable properties (brightness, loudness, temperature, wavelength and relative strength) (MA)
  • Develop a model demonstrating how energy can be transferred from one object or system to another (or from a system to its environment) in different ways (MA)
  • Explain how heat energy is transferred by convection, conduction and radiation (MA)
  • Recognize that magnetic and electrical forces between two objects at a distance can transfer energy between the interacting objects (MA)

 

 

Force and Motion

 

  • Illustrate how a static object (e.g., table) can exert a force on another object (MA)
  • Measure the mass of an object. Recognize that mass is the amount of matter in an object. Differentiate mass from weight (MA)
  • Predict motion of an object acted upon by multiple push/pull forces
  • Explain and give examples of how the motion of an object can be described by its position, direction of motion, and speed (MA)
  • Describe and diagram the qualitative relationships among force, mass and changes in motion.
  • Draw a force diagram with co-linear forces to determine the net force acting on an object (MA)
  • Explain how a net force resulting from more than one force acting on an object along a straight line may cause a change in the object’s linear momentum (speed or direction). (MA)
  • Create and interpret speed vs. time and position vs. time graphs (MA)
  • Investigate and describe the effects of friction on the motion of objects (MA)
  • Calculate the average speed of a moving object and illustrate the motion of objects in graphs of distance over time.
  • Describe the forces acting on an object moving in a circular path.
  • Use examples of energy transformations from one form to another to explain that energy cannot be created or destroyed

 

 

Matter

  • Recognize that all chemical changes involve changes in energy (MA)
  • Explain that bonds are forces similar to the force exerted between two magnets, but that there is nothing between particles (MA)
  • Observe and record evidence to show that a chemical change is often accompanied by observable phenomena such as precipitation, gas evolution, change  in temperature or change in color 
  • Use a particulate model of matter to explain that density is the amount of matter (mass) in a given volume. Measure the mass and volume of an object and calculate its density. (MA)
  • Give examples to show how the physical characteristics of elements and types of reactions they undergo were used to create the Periodic Table
  • Use the Periodic Table as a tool to predict, compare and contrast compounds and elements

 

Engineering (Bottle Rockets)

  • Complete the engineering design cycle when given specific criteria, materials and constraints
  • Use the design process to evaluate the effect of variables such as fin mass, angle, size, curvature, material, number of fins, area, shape, recovery systems, etc. in solving their problem ie.  launching a rocket.
  • Identify evidence of lift, drag, thrust forces interacting in the system
  • Identify action-reaction forces.
  • Explain how pressure influences rocket performance.
  • Explain the effect of mass (inertia) on the ability of an object to be accelerated.
  • Act as productive, collaborative team members.
  • Make accurate measurements, observations and record data on a data sheet

 

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