How to Use a Star Wheel

star wheel
  • The star wheel is a simple tool for seeing which stars and constellations are visible in the sky at a given date and time.
  • Star wheels are designed to work at a specific latitude. For example, a star wheel that is accurate in Dallas wouldn't be of much use in New York. The star wheel your team will use for this part of the lab is designed to work for latitudes around 40° N (Iowa City is at around 41° N).
  • Rotate the wheel until the date of interest lines up with the time of day you want. You can find positions for both Daylight Savings Time (Yellow) or Standard Time (White).
  • The oval in the center of the star wheel shows the stars above the horizon at the designated date and time and also displays the compass directions.
  • While a star wheel like this one is not very good for finding precise coordinates of objects in the night sky, it is a very simple tool for naked eye or small telescope observations.