How Many Stars?

How Many Stars in the Observable Universe?

This is an estimation challenge problem where you attempt to estimate the total number of stars in the observable universe. There is no template for you to use for this problem. The instructions are contained in the Google Doc below. You are free to choose the format you wish to present your work and the format you would like to turn it in (electronic via Google & sharing with slindsay at utk.edu ; hand-written; LaTeX; Word; etc.)

Link to a PDF with the HUDF image embedded in it. A hint to solve this problem is to print it out so you can more closely examine it and count things.  LINK TO PDF

Difficult Level: 5

Full Points Due Date: Tuesday, 18 February

Rewards for Building the Problem-Solving Strategy

+10 Problem-Solving Points

+10 Critical Thinking

Collaboration Points: +5*N, where N is the number of people you collaborated with. You must divide the total number of collaboration points amongst yourselves and clearly report that in your submission to Dr. Lindsay

So, You Want to Solve It?

If you want to present a full solution to earn extra points and get that satisfication from a good problem solved, then you must:

• List all your assumptions and justify your approximations

• Provide a clear write-up of the your solution

  • I am looking for a step-by-step solution with explanations of each step taken

Additional Reward for Solving the Problem

+8 Problem-Solving Points

Additional Collaboration Points: +5*N, where N is the number of people you collaborated with. You must divide the total number of collaboration points amongst yourselves and clearly report that in your submission to Dr. Lindsay

Research Points

Up to +15 Research Points

Find a peer-reviewed astronomy journal article that provides an estimation for the number of stars in the Milky Way galaxy, the number of galaxies in the universe, or the number of stars in observable universe. Summarize the observations, methods, and results of the study. Compare your estimate (or parts of your estimate) to their estimate.

+5 additional research points: Provide a summary of the papers you found along your journey