Put dust in the light’s way
Turn a dusty pillar around. Change how much material lies in the light path and see why more matter can look darker.
Preparing the experiment
Illustrative modelDrag to orbit · scroll to inspect
Glowing gas behind · dark dust in front · a direct beam loses light in the dust
An illustrative pillar and beam. Changing the dust does not reveal hidden information in the photograph. The model isolates absorption; real dust also scatters light.