What can the occult do for you?

Understand

Interstellar dust is still a dominant uncertainty in Astronomy, limiting precision in e.g., cosmological distance estimates and models of how light is re-processed within a galaxy.

• When a foreground galaxy serendipitously overlaps a more distant one, the latter backlights the dusty structures in the nearer foreground galaxy.
• Such an overlapping or occulting galaxy pair can be used to measure the distribution of dust in the closest galaxy with great accuracy.
• The STARSMOG program uses Hubble to map the distribution of dust in foreground galaxies in fine (<100 pc) detail.