Infrared Astronomy - Physics Demonstrations - Infrared Astronomy | Physics Undergraduate Labs

Use fog/smoke machines in well-ventilated areas. Allow adequate dispersal time before ending class. Some individuals may have respiratory sensitivities—announce fog use at start of demonstration and allow sensitive individuals to relocate if needed. Follow institutional policies regarding theatrical fog use in classrooms.

Purpose

Shows how IR imaging reveals objects invisible to optical cameras and penetrates fog/dust clouds that block visible light. Students learn why IR telescopes are essential for observing cool objects, star-forming regions, and the galactic center.

Infrared camera display panel wrapped in clear plastic with blue tape on edges, sitting on a table

Infrared thermal image showing a hand's warm fingers (bright yellow-white) against a cooler purple-pink background

Figure 1: The infrared camera display used for the demonstration, shown in visible light.

Figure 2: Infrared image of a hand placed behind the display. The warm fingers appear bright in thermal emission, invisible to the optical camera.

Safety Warnings

Warning: Fog Machine Safety

Purpose