Solar System

Solar System 17: Choosing a Mission

In this culminating activity, students are tasked with determining which space mission to Titan should be funded as a future NASA endeavor. Students weigh the trade-offs between the new technology that might result from the mission and the amount of potential data and information that can be collected. This activity helps students understand how space missions are chosen and what type of information is still being learned about our Solar System. Presented with three proposed missions, students must recommend one. To aid their decision-making, students discuss the feasibility of each mission and what it could accomplish. Student groups make a decision based on information in the mission proposals and content from the previous activities. As a culmination of their work on the issue, each student then writes a letter citing the evidence that forms the basis of their recommendation.

Solar System 16: Modeling Gravity

This activity has students use a computer simulation to observe how gravity is responsible for the motion of objects within our Solar System. By modifying the distance between objects and the mass of objects, students are able to observe how these variables affect the orbital periods of planets in our Solar System. Extending this concept, students are able to calculate the mass of the Sun. They complete a short reading relating their model to the motion of stars and solar systems within a galaxy, featuring the pioneering work of astronomer Vera Rubin. Students conclude the activity by developing and using a model to describe the role of gravity in the motion of space objects within solar systems and galaxies.

Solar System 15: Gravitational Force

Students read about gravity’s role in our Solar System, in terms of both what we currently observe about the objects orbiting our Sun, and how our Solar System formed. They are introduced to the concept that the objects in our Solar System orbit the Sun due to the gravitational interaction between each object and the Sun. The reading about gravity summarizes for students the relationship between mass, distance, and gravitational force. Students also read about gravity’s role in the orbits of space objects. Students read about how gravity was responsible for the formation of our Solar System and Galaxy.

Solar System 14: Gravitational Force

Students are introduced to the concept of gravity. To understand what gravity is, students are given data sets relating gravitational force to the mass of two objects and the distance between two objects. Students look for patterns in the data. Students are introduced to some characteristics of gravity as they explore the relationship of gravitational pull to distance and mass. They graph the gravitational force between Saturn and some objects in its orbiting rings. Students compare the gravitational force of smaller- and larger-mass objects orbiting at the same distance from the planet, and of objects of equal mass orbiting at different distances from the planet.

Solar System 13: Identifying Planets

In this activity, students are given data corresponding to scaled properties of different planets in the Solar System. They are given four descriptions of different planets based on actual space missions. They use these descriptions and their analysis of the planetary data to identify which planets in our Solar System the spacecraft traveled to. Students use their growing understanding about objects in our Solar System and how one can differentiate between objects based on their properties. This experience encourages students’ sensemaking around how astronomers and other scientists use and analyze data to categorize and identify space objects.

Solar System 12: How Big are the Planets?

While the scale used in the “Drawing the Solar System” activity works for comparing planetary distances, a different scale is needed to compare the sizes of planets.  Students explore the sizes of planets in the Solar System, and create a physical model showing the relative sizes of the planets. They select an appropriate scale, calculate the diameter of the scaled objects, and find round objects that accurately represent the size of each planet. By developing their own model, students can connect their intuition and knowledge about the planets with actual measurements related to the size of each planet. They consider how large the Sun would have to be in their scale model.

Solar System 11: Drawing the Solar System

To help students understand the size and scale of the Solar System, they are tasked with developing a scale model of the distances between the Sun and the different planets in our Solar System. To test whether their scale works, they are asked to draw the distances between the Sun and each planet on a single piece of paper, making sure that their distances are scaled properly. Using a distance scale, students calculate the distance from the Sun to each planet in the Solar System. They make a model of the Solar System by drawing the scaled distance to each planet. Using the same scale, they investigate the diameters of the planets and discover that the scale used for distances in the Solar System is inadequate for drawing an accurate model of each planet.

Solar System 10: Observing Objects in Space

Now that students have experience with observing patterns to better understand phenomena, they are asked to think about space objects that are much farther away and more difficult to observe. Students are given images of space objects as viewed from Earth to help them recognize how difficult it is to tell how big or far away something is based on just a picture taken from Earth’s surface. Students are then shown images that have been taken with advanced technologies so they can analyze data in order to categorize the different objects found in our Solar System and beyond.

Solar System 9: Earth on the Move

Students read about how Earth’s tilt relative to its orbital plane is the reason for the pattern of seasonal changes experienced on Earth’s surface. The reading prompts students to think about how both the amount and the intensity of sunlight are related to the temperature at Earth’s surface, and how changes in temperature relate to the seasons. Students then develop models to explain these phenomena. 

Solar System 8: Earth's Tilt

Students continue to explore the effect of Earth’s tilt in determining the seasons. Two teacher demonstrations show that light is more concentrated, or less spread out, when it strikes a surface at a 90-degree angle than at any other angle. Students use a model to determine how the angle of the Sun relates to the amount of solar energy received at a given area on Earth’s surface. Students model how Earth's tilt affects the interaction between solar energy and Earth’s surface in the Earth–Sun system. To do this, students test how the angle of a solar cell, relative to the direction of incoming sunlight, affects the amount of electricity produced by the solar cell. This model allows students to observe why the angle of the Sun is related to the pattern of seasonal changes experienced on Earth.

Solar System 7: A Year Viewed from Space

Students use an interactive computer simulation to view Earth’s orbit around the Sun. The scale used in this model allows students to observe what Earth’s tilt is and how Earth’s tilt is related to the number of hours the Sun is up during the different months of the year. Students analyze and interpret data to determine that Earth’s distance from the Sun doesn’t change much over the year, and is actually closest to the Sun in early January.

Solar System 6: Changing Sunlight

Students graph and analyze data on length of daylight and the angle of the Sun during the course of a two-year period in the Northern Hemisphere, and relate the patterns they observe to seasonal changes. They discover the correlation between daylight length and the position of the Sun in the sky, and relate these variables to the seasons. This awareness of seasonal patterns in the Sun’s position and apparent motion prepares them for a discussion of the reasons behind these changes in the next three activities.

Solar System 5: The Moon's Orbit

Students manipulate a physical model of the orbital plane in which the Moon travels as it orbits Earth. This three-dimensional model allows students to investigate why eclipses, both lunar and solar, are relatively rare. This activity is the final opportunity in this unit for students to cement their understanding of why the Moon’s orbit results in changing moon phases as seen from Earth.

Solar System 4: Moon Phase Simulation

Working at computers, students interact with a two-dimensional simulation that shows the direction of sunlight and the relative positions of Earth and the Moon as Earth rotates and the Moon orbits Earth. Students sketch what they observe in the computer simulation and build their understanding of how the Moon orbits Earth. They connect this experience with their observations of the Moon’s phases and the physical models used in the previous activities. This model helps bridge the gap in their knowledge regarding how much time it takes for the Moon to orbit Earth and how that relates to the time it takes for the pattern in Moon phases to repeat.

Solar System 3: Explaining the Moon's Phases

Students use a physical model to understand how interactions within the Earth– Sun–Moon system cause each phase of the Moon to have the appearance it has. To do this, students use a model to determine how light from the Sun makes different amounts of the Moon visible from Earth depending on where the Moon is relative to Earth and the Sun. They connect their recorded observations of the model with the pattern they identified in “The Predictable Moon” to describe what causes the Moon’s phases. The model uses a light to represent the Sun and a white ball to represent the Moon and a student's head to represent the Earth. Their eyes represent the view of a person standing on the surface of the Earth looking at the moon. . This model introduces students to the idea that the Moon’s phase at any given time depends on the Moon’s changing position relative to Earth and the Sun as the Moon orbits Earth.

Solar System 2: The Predictable Moon

Students order the phases of the Moon, based on their own experiences and observations. Students use Moon Phase Cards to make observations about the different phases of the Moon and to look for patterns. Once they identify the pattern of the cycle of the Moon’s phases, they examine observations of the Moon made over a period of time. They establish that the cycle of the Moon’s phases is a little shorter than a typical month on Earth. The students then figure out whether there is a predictable and repeating pattern in how the Moon’s appearance changes over time. Using the pattern they discover, they analyze and interpret data on an incomplete Moon phase calendar and determine which phases occur on the missing days.

Solar System 1: Exploring Space

To begin the Solar System unit, students brainstorm questions to add to our Driving Question Board. They thought about the Unit Issue, "Choose a proposed space mission based on which missions have the most potential for technological advancements and better scientific understanding." and the Anchoring Phenomena, "There are a variety of objects in space and they move over time. Technology plays a critical role in learning more about these objects." Then students generated questions.  After sharing out their questions, they wrote the question they most want to answer on a sticky note. We then looked at the five driving questions for the Solar System Unit, and placed their questions near the driving question closest to their own. 

• How can we learn more about space? 

• How can we use observations and models to understand the Moon phases? 

• What are the other objects in our universe, and how far away are they? 

• What determines how objects move in space? 

• Why does the Sun’s path through the sky change over the year, and how does that change relate to seasons? 

In Activity 1, students learn how space exploration has expanded our understanding of the Solar System and beyond. Students consider the challenges involved with space exploration. They learn how advances in engineering and technology have made space exploration possible. Students read about different missions to space that have helped scientists understand more about our Solar System and beyond. Each mission description includes information about what was learned and some of the technological challenges faced by the mission. Students then share what they learned and discuss the tradeoffs between exploring space with spacecraft and using research money elsewhere. The links below from the SEPUP Website include additional information about the NASA Missions featured in the student book. 

All NASA Missions
This page has links to each of NASA’s missions.

Hubble Space Telescope
The NASA webpage for information on the Hubble Space Telescope.

Apollo Program
The NASA webpage for information on the Apollo Program.

Cassini Mission
The NASA webpage for information on the Cassini Mission.

Curiosity Rover
The NASA webpage for information on the Curiosity Rover.