The OCStarring:
M11 and NGC 6819
Jared Rosen, Becca Gallery, and Molly Zimmerman
• Young and large stars
• Few thousand per cluster
• Not as compact as globular clusters
• More massive stars so shorter lifetimes!
• All born from the same molecular cloud
• Stars all about same age and distance
Open Clusters
NASA/ESA/AURA/Caltech.
Color and Temperature
Stellar Evolution
• Star formation
• Main sequence
• Red giants
Star Formation
Main Sequence
Hot cold
Bright
• Where stars spend most of lifetime
• Hydrogen burning
•Our sun is on the main sequence
• Massive stars have shorter lifetimes
• Massive stars are bright and hot
dim
Red giant
No fusion but gravitational contraction
Red Giants!
•Burning hydrogen shell
•Evolved past main sequence
•No hydrogen burning in core
•Size expands and star brightens but temperature decreases
Taking Pictures
• Late night conference with Ellie (telescope operator)
• M11 and NGC 6819
• Exposure times
• Filters/ RGB images
RGB Images
+ +
=
= Color
ma
gn
itude
redblue
Main sequence
Red Giant Branch
= Colorblue red
ma
gn
itude
Main sequence
Red Giant Branch
Red clump
NGC 6819 vs. M11 NGC 6819 = 3 billion years old m11= 200 million years old
Distances
• M11 = 2600 parsecs or 8700 light years
• NGC 6819 = 1400 parsecs or 4500 light years
Galaxy Model
Conclusion
• Using CMDs and Isochrones we were able to figure out our ages, brightnesses, and distances of our open clusters
• M11 = 8700 light years and 200 million years old
• NGC 6819 = 4500 light years and 3 billion years old
Thank you!!!• Andrea Michels• Chris Martell• Ellie Gates• Greg O’Bryan• Globs: Catherine
and Amanda• Hilary O’Bryan• Jason Porter
•Jay Strader•John Martin•Kathy Cooksey•Kirsten Howley•Laura Chomiuk•Monica Piñon•Malika Moutawakkil-Bell
COSMOS