Mars for Earthlings > Lesson Modules > In-Class Activity 1- Measuring the Tiny

Measuring the Tiny

In-Class Activity 1_Views and Missions in Space

Julia Kahmann-Robinson PhD and Marjorie Chan PhD, University of Utah Department of Geology & Geophysics


Determine a method to detect elements of interest (water and/or life-indicating) on Mars and become familiar with mass spectrometer devices on Mars-bound missions.


  • Display a periodic table
  • Bring any type of rock to class
  • Internet connection in classroom


NASA Mass Spectrometer Video:


Display a picture of the periodic table and ask students the following questions:

1. What are the differences between the elements of C, K, and O?

2. How could you measure their differences strictly from a principle standpoint?

3. As students provide answers, make sure they understand that an element's mass is its most unique features (charge is not, so you can point a common misconception).

Explore (Corresponds with "measuring the tiny" in the student version)

Ask students to brainstorm a method, in teams, that would measure how much of each element was present in the rock you brought to class.

1. Can they turn this method into an instrument? What are the pros and cons/challenges?

2. Could they use this instrument to detect these elements on Mars? Why or why not? What are the engineering design challenges?


Watch the following NASA Mass Spectrometer Video:


Send students on a treasure hunt or provide specific link where they can do secondary research. Possibly discuss the value of research as a scientific tool. What are the priorities of payloads of various Mars orbiters and rovers? How do the priorities affect whether one could house mass spectrometer instruments?

Possible links include:

Mars Science Laboratory Spectrometer:

NASA Mass Spectrometry 101:


What elements would NASA like to detect to infer the possibility of extraterrestrial life?

After watching the NASA Mass Spectrometer video, ask students how the methods or instruments they brainstormed about compare to NASA's methods.

Ask students to describe how Mass Spectrometry works.

Students can watch this video (note the large size of this instrument):

Why is it so difficult to get Mass Spectroscopy instrument on NASA robots or probes?

ethod/instruments compare.