Temperature and Thermal Inertia Maps

This page contains directions for displaying differences between night and day temperatures and the tendency for the Mars surface to hold heat, which is called thermal inertia. This page also contains directions for displaying Mars calculated daily and yearly temperatures.*

Temperature Maps

The THEMIS IR Night Map shows nighttime temperatures, which can be compared to the daytime map captured in the visual wavelength.

Day and Night Time Maps

Open JMARS
Go to your area of interest and zoom in.
In the Layers window, click the“Day temperature” (IR) Layer and drag that layer to the top.
Click and drag the “Nighttime Temperature” l(IR) layer under the Daytime layer.
In the “Daytime Temperature” move the slider back and forth to change the layer transparency.
Observe differences and ask questions.

Daytime Temperature Map

Nighttime Temperature Map

Temperature Charts

1. Open JMars

2. Zoom in to location(s) of interest.

3. Click on "Layers"; under "Search," type in KRC. Choose "Temperature Calculator".

4. Close the "add new layer" window if it stays open.

4. Click on location of interest. Change name if desired. Choose "add" in pop up.

5. Repeat step 4 for all locations of interest.

6. Double click on "KRC layer".

7. Choose "Results" tab.

8. Select all rows with locations you want graphed. e.g. hold shift click.

9. Click: "run KRC for necessary data point(s)." Wait ~10-20 seconds. Note: created graph has two tabs: Day and Year.

10. Options: Change variables like the time of day, albedo, and/or slope to see what effects it has. For more options see video1 or video2. (Changing the time of day effects only the year chart.)

*KRC is a computer program designed to compute surface and subsurface temperatures for planets and satellites with or without modest atmospheres. the acronym KRC is simply K for conductivity, R for “rho” (ρ) for density, and C for specific heat—the three terms in thermal inertia. Reference

Example 1

Example 2

A comparison of daily temperatures at the summit and base of Olympus Mons using KRC data reveals intriguing patterns. Key questions to consider:

Why is the base warmer than the summit?
What causes the sharp slope in the temperature data at the summit?
Why does the temperature remain constant throughout the night?

These observations invite exploration of factors such as atmospheric density, surface materials, and heat retention at different elevations.

Thermal Inertia Map

Thermal inertia refers to a material's ability to conduct and store heat. In planetary science, it measures the subsurface's capacity to absorb heat during the day and release it at night. Factors influencing thermal inertia include bulk density, particle size, and the degree of cementation. Learn more: HiRISE: ESP_039485_1660.

Open JMARS
Make the "Explore Mars" Layer the top layer and move the "Thermal Inertia" layer under it. See screen shot on theright.
Move the slider back and forth in the "Explore Mars" Layer to change the layer transparency.
Zoom in as desired.
Observe differences and ask questions.
See the next page to make day and yearly profiles of any location on Mars!
You may want to google what variables affect thermal inertia on Mars to give you more insight.

Example