The Distance and Age of an Open Cluster

Star clusters can serve as important tools to study the star formation, the dynamics of the ISM, and the evolution of our galaxy. They provide Astronomers the opportunity to study stellar populations where members might share many observational properties. These properties may include astrometry (space velocities, group dispersion), metallicity, and, pertaining this lab, distance and age.

This lab will introduce students to H-R diagrams, stellar clusters, and how different clusters might appear on these H-R diagrams. Additionally, we will explore how an H-R diagram might allude to the distance and age of a cluster, estimating the distance to Messier 35, and using cluster isochrones to find the age of NGC 752.

Lab Resources

Download the required data files from the link below. Be sure to extract them and save them somewhere on your Google Drive!

Once you open the Colab notebook link above, be sure to click File -> Save a copy in Drive before beginning your work! This will allow you to save your changes.

Further Readings

  • Introduction to stellar classifications
    Astronomy, Fraknoi, Morrison, and Wolff (2018). Section 17.3 (Pages 602-610).
  • Stellar magnitudes
    Astronomy, Fraknoi, Morrison, and Wolff (2018). Section 17.1,  Pages 595-599.
  • Colour indices and temperature
    Astronomy, Fraknoi, Morrison, and Wolff (2018). Section 17.2, Pages 600-602.