Science Buddies: "Ask an Expert"

Hello. I am doing the project 'How Old Is The Universe'. I have made a luminosity vs color(g vs g-r) scatter graph, my first turning point is g=14.578 and g-r=0.675562 but when I compare it to the table(seven characteristics of stars in their spectral cases) which is located in the introduction,the numbers for luminosity and colour do not seem to match up. Do you have any advice please?

Hi 15hlucey,

I’m assuming that you are working on the project described here:

https://www.sciencebuddies.org/science- ... p042.shtml

The procedure for making the H-R diagram seems rather involved. You might want to carefully review your work to make sure that each step was completed properly. Specifically, you want to be sure that you’ve selected the correct data columns in the “CSV” file. And you want to be sure that you have the correct data plotted on the x- and y-axes.

I hope this helps. Please post again if you have more questions.

A. Norman

Hi ,

I'm getting the exact same problem

I'm confident I am plotting everything correctly , the problem is the g values output are never below 15 , from my extensive research the Luminosity should be low , 0.6 to 1.5 , to classify the age of the universe from these clusters...the colour values are in the right region to classify 0.3 to 0.6 but the Luminosity is way too high...

Am I doing or have I understood something fundamentally wrong here or is there a problem with the project?