Code Number: 8B30.10
Demo Title: Stellar Magnitude
Condition: Good
Principle: Stellar Magnitude
Area of Study: Astronomy
Procedure:
The 1000 watt, 100 watt, and 1/4 watt bulbs will give some idea of stellar magnitudes.
If the brightness of each bulb scales linearly, the 100 watt bulb will be 400 times brighter than the 1/4 watt bulb, and the 1000 watt bulb will be 4000 time brighter. From that should be able to do a calculation of brightness vs. distance. For instance, if the 1/4 watt bulb is at a fixed distance from the observer, how far away would the 100 or 1000 watt bulbs have to be moved to have the same observed brightness as the 1/4 watt bulb.
References:
- Prof. Thomas Hocket, "Luminosity, Brightness, and Distance", TPT, Vol. 52, # 1, Jan 2014, p. 6.
- E. S. Oberhofer, "Different Magnitude Differences", TPT, Vol. 29, # 5, May 1991, p. 273.
- Christopher Sirola, "I Love My Baffling, Backward, Counterintuitive, Overly Complicated Magnitudes", TPT, Vol. 55, #2, February 2017, p. 124-125.
- Chirstopher Sirola, "Stellar photometry in an introductory physics lab (or, translating flux into magnitudes)", TPT, Vol. 61, #4, Apr. 2023, p. 310.
- Eric Schulman and Caroline V. Cox, "Misconceptions about Astronomical Magnitudes", AJP, Vol. 65, #10, Oct. 1997, p. 1003.
- James A. Blackburn, "Integrated Circuit Stellar Magnitude Simulator", AJP, Vol. 46, #8, Aug. 1978, p. 813.
- Donald C. Warren, "Cosmic Extremes of Luminosity", Physics Today, Vol. 78, #2, Feb. 2025, p. 54.
- Janice VanCleave, "Star Bright", Constellations for Every Kid, p. 141.