8B30.10 - Stellar Magnitude

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.
  • Janice VanCleave, "Star Bright", Constellations for Every Kid, p. 141.


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