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Computer Program Detail Page

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Leavitt's Cepheid Variables
written by Todd Timberlake
The Leavitt's Cepheid Variables Model allows the user to explore the relationship between period and apparent magnitude for Cepheid variables in the Magellanic Clouds, first discovered by Henrietta Levitt in 1912.  The main window displays a photographic negative of a star field.  When the simulation is played, the main window displays an animated sequence of photo negatives taken at 1 day intervals.  Each star field contains one Cepheid variable star, which can be identified by its changing size in the photographic negative.

A tool for measuring apparent magnitude is provided, and a plot of the light curve (modulo a test period) can be displayed.  These tools let the user measure the median apparent magnitude and period of the Cepheid variable. Resetting the simulation generates a new star field, so the user can measure many Cepheid variables and discover the relationship between period and luminosity for these stars, originally found by Leavitt for the star in the Small Magellanic Cloud.

The Leavitt Cepheid Variables Model was created using the Easy Java Simulations (EJS) modeling tool.  It is distributed as a ready-to-run (compiled) Java archive.  Double clicking the ejs_LeavittCepheidVariables.jar file will run the program if Java is installed.

Please note that this resource requires at least version 1.5 of Java (JRE).
1 source code document is available
Subjects Levels Resource Types
- Astronomy Education
= Curricula
- Cosmic Time and Distance
= Cepheids
= Distance Scales
= Standard Candles
- Historical Astronomy
= History of Astronomy
- Lower Undergraduate
- High School
- Instructional Material
= Interactive Simulation
Intended Users Formats Ratings
- Learners
- Educators
- General Publics
- application/java
  • Currently 0.0/5

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Access Rights:
Free access
This material is released under a GNU General Public License Version 3 license.
Rights Holder:
Todd Timberlake
Cepheid, EJS, Easy Java Simulations, Henrietta Leavitt, OSP, Open Source Physics, light curve, period-luminosity, variable star
Record Cloner:
Metadata instance created July 3, 2012 by Todd Timberlake
Record Updated:
June 10, 2014 by Andreu Glasmann
Last Update
when Cataloged:
July 3, 2012
ComPADRE is beta testing Citation Styles!

Record Link
AIP Format
T. Timberlake, Computer Program LEAVITT'S CEPHEID VARIABLES, Version 1.0 (2012), WWW Document, (https://www.compadre.org/Repository/document/ServeFile.cfm?ID=12170&DocID=2997).
T. Timberlake, Computer Program LEAVITT'S CEPHEID VARIABLES, Version 1.0 (2012), <https://www.compadre.org/Repository/document/ServeFile.cfm?ID=12170&DocID=2997>.
APA Format
Timberlake, T. (2012). Leavitt's Cepheid Variables (Version 1.0) [Computer software]. Retrieved June 24, 2024, from https://www.compadre.org/Repository/document/ServeFile.cfm?ID=12170&DocID=2997
Chicago Format
Timberlake, Todd. "Leavitt's Cepheid Variables." Version 1.0. https://www.compadre.org/Repository/document/ServeFile.cfm?ID=12170&DocID=2997 (accessed 24 June 2024).
MLA Format
Timberlake, Todd. Leavitt's Cepheid Variables. Vers. 1.0. Computer software. 2012. Java (JRE) 1.5. 24 June 2024 <https://www.compadre.org/Repository/document/ServeFile.cfm?ID=12170&DocID=2997>.
BibTeX Export Format
@misc{ Author = "Todd Timberlake", Title = {Leavitt's Cepheid Variables}, Month = {July}, Year = {2012} }
Refer Export Format

%A Todd Timberlake %T Leavitt's Cepheid Variables %D July 3, 2012 %U https://www.compadre.org/Repository/document/ServeFile.cfm?ID=12170&DocID=2997 %O 1.0 %O application/java

EndNote Export Format

%0 Computer Program %A Timberlake, Todd %D July 3, 2012 %T Leavitt's Cepheid Variables %7 1.0 %8 July 3, 2012 %U https://www.compadre.org/Repository/document/ServeFile.cfm?ID=12170&DocID=2997

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Leavitt's Cepheid Variables:

Is Based On Easy Java Simulations Modeling and Authoring Tool

The Easy Java Simulations Modeling and Authoring Tool is needed to explore the computational model used in the Leavitt's Cepheid Variables.

relation by Wolfgang Christian

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