Star Walk 2 - Dave Farina

Author

Dave Farina

Sensor / Probe

Star Walk 2 utilizes the gyroscope and accelerometer in your smartphone to create an augmented reality experience that aids in the identification and exploration of celestial bodies. Holding your phone up to match your screen to the backdrop of the sky, GPS generates an informational overlay that brings constellations to life and transmits information about the various objects in view. Some of the types of objects that can be examined include:

  • stars

  • planets

  • constellations

  • comets

  • meteors

  • satellites

  • deep sky objects

There are several modes of operation as well, including "time machine" mode, which allows for viewing of the night sky as it would appear at any point in the past or future.

Sample Investigation

Due to a variety of functionality, it can be used to teach concepts at different levels.

Module 1: Identifying the Planets and Ecliptic

1) Using the search function, locate and identify all the planets in the solar system:

Mercury, Venus, Mars, Jupiter, Saturn, Uranus, Neptune

2) Notice that they all seem to be arranged on a line of some kind. What could this line be? How is it possible that they move in this manner?

3) Draw a model of the solar system, including Earth, and try to model what you have learned about the solar system with the positions of the planets.

Jupiter and the Ecliptic

Module 2: The Electromagnetic Spectrum and Celestial Objects

1) In the settings menu, enable the spectrum bar.

2) Choose a region of the sky, and slowly shift through the electromagnetic spectrum:

Gamma Ray, X-Ray, Visible, H-Alpha, Infrared, Microwave, Radio

3) For each category of light, write down some observations about what you see, and any significant changes from the previous setting.

4) With your class and instructor, discuss some of the reasons why these changes occur. What is it that is being seen for each part of the spectrum that can't be seen in other parts, and why?

5) There is one region of the sky that changes the most throughout this process. What is this, exactly? For which range does this section stand out the most? Why might that be? For which region of the spectrum does this section become the most pronounced?

Module 3: The Speed of Light and Universal Expansion

1) Access the time travel function and choose a region of sky. Now travel back in time by one million years and note any changes you might see. Then travel one million years into the future, and again note any changes.

2) What are the primary mechanisms in action that cause the sky to appear differently in different eras of cosmological history? If new stars appear, between the past and the present, how did they form? If some stars disappear from the present to the future, where did they go? Discuss stellar formation and the lifetime of the star.

3) Choose a star with a known distance from the Earth. How far is this star? When you look into the night sky, are you seeing this star as it is today, or as it once was? If the latter, how long ago?

4) See if you can make some conclusions about the distances and positions of other galaxies as you toggle the time setting. What can we say about the relative positions of the galaxies as time moves forward, and what does this mean for the universe?

Sample Data & Analysis and Interpretation

For Module 1, students will learn about the ecliptic, and the notion that the solar system exists more or less in one flat plane. This will aid in cementing an understanding of the motion of objects within our solar system, and serve as an introduction to celestial dynamics.

For Module 2, students will discuss the sources of electromagnetic radiation of various frequencies, which can serve as an introduction to many different phenomena, like stellar classification, pulsars, black holes, cosmic background radiation, etc. Furthermore, they will identify the plane of the Milky Way galaxy, and acknowledge that it is not the same plane as the plane of the solar system. This will aid in developing a tiered understanding of galactic structure.

For Module 3, students will discuss the evolution of the galaxy and the universe. They will discuss the lifetime of stars, their birth and death, and their slowly changing positions in the sky. Furthermore, analysis of other galaxies can be an entry-point to a discussion regarding recession velocities, the expansion of the universe, and even dark energy.

Photos

Movies

References

Get the Android app here.

Get the Apple app here.