Dust collects on things that are old or forgotten. Dust has a bad name on Earth, while elsewhere in the Universe, it turns out to be a key ingredient of the life cycles of stars and planets.

 

The proliferation of exoplanet discoveries over the last two decades has also been accompanied by a greater understanding of how planets form around stars. Truly,  planets come from star dust, or the left over material from the gravitational collapse of a gas cloud into a hot, nuclear powered furnace. The actual details of how this occurs, however, is still literally shrouded in mystery.

 

One often needs a radio or infrared telescope to peer through the dark, dusty regions around forming stars and planetary systems. Sometimes, these instruments can be used to view the dust itself, which holds valuable information about the physics involved.