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

Themis IR night map displays nighttime temperatures, which can be compared to the visual wavelength Daytime map.

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 between the daily temperature on top of Oympus Mons and on the bottom of Olympus Mons using KRC data. Questions to think about: Why does the bottom get warmer than the top? Why is there a sharp slope on the top data? Why does the temperature stay the same as the night progresses?

Thermal Inertia Map

Thermal Inertia is the ability of a material to conduct and store heat. In planetary science, its measure of the subsurface’s ability to store heat during the day and reradiate it during the night. Variables determining thermal inertia are bulk density, particle size, and cementation. https://www.uahirise.org/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