Dissertation
Dusty perspectives on the cradles of planets
Astronomy began by studying the light from the stars. These stars are born in vast clouds of gas and dust.
- Author
- O.M. Guerra Alvarado
- Date
- 06 February 2026
- Links
- Thesis in Leiden Repository
My PhD research used some of the world’s most advanced telescopes, including the Atacama Large Millimeter/submillimeter Array (ALMA), to look very closely at the dusty material around young stars. This dusty material, known as a protoplanetary disk, forms the cradle where planets are born. By observing these disks at several wavelengths and modelling how light travels through them, we can measure how dust grains grow, clump, and settle, the first steps toward building planets.
In my research, I first studied the dust and molecules in an extremely young stellar system and found evidence that dust grain accumulation, and thus planet formation, begins very early in a disk’s lifetime. In the same system, complex organic molecules were distributed in intricate patterns linked to the way the dust is evolving. I then turned to slightly older disks and, using higher-resolution data than previous studies, found that two-thirds of the disks in a single star-forming region are very small, contradicting the earlier belief that disks are usually large.
Together, these results show that disks are far more diverse and complex than previously thought, reshaping our understanding of how common large, Solar System–like planetary systems, and possibly life itself, may be.